| Network Working Group | C. Daboo |
| Request for Comments: 4791 | Apple |
| Category: Standards Track | B. Desruisseaux |
| Oracle | |
| L.M. Dusseault | |
| CommerceNet | |
| March 2007 |
Calendaring Extensions to WebDAV (CalDAV)
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the “Internet Official Protocol Standards” (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
Copyright � The IETF Trust (2007). All Rights Reserved.
This document defines extensions to the Web Distributed Authoring and Versioning (WebDAV) protocol to specify a standard way of accessing, managing, and sharing calendaring and scheduling information based on the iCalendar format. This document defines the "calendar-access" feature of CalDAV.
The concept of using HTTP [RFC2616] and WebDAV [RFC2518] as a basis for a calendar access protocol is by no means a new concept: it was discussed in the IETF CALSCH working group as early as 1997 or 1998. Several companies have implemented calendar access protocols using HTTP to upload and download iCalendar [RFC2445] objects, and using WebDAV to get listings of resources. However, those implementations do not interoperate because there are many small and big decisions to be made in how to model calendaring data as WebDAV resources, as well as how to implement required features that aren't already part of WebDAV. This document proposes a way to model calendar data in WebDAV, with additional features to make an interoperable calendar access protocol.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].
The term "protected" is used in the Conformance field of property definitions as defined in Section 1.4.2 of [RFC3253].
When XML element types in the namespaces "DAV:" and "urn:ietf:params:xml:ns:caldav" are referenced in this document outside of the context of an XML fragment, the string "DAV:" and "CALDAV:" will be prefixed to the element type names, respectively.
Definitions of XML elements in this document use XML element type declarations (as found in XML Document Type Declarations), described in Section 3.2 of [W3C.REC-xml-20060816].
The namespace "urn:ietf:params:xml:ns:caldav" is reserved for the XML elements defined in this specification, its revisions, and related CalDAV specifications. XML elements defined by individual implementations MUST NOT use the "urn:ietf:params:xml:ns:caldav" namespace, and instead should use a namespace that they control.
The XML declarations used in this document do not include namespace information. Thus, implementers must not use these declarations as the only way to create valid CalDAV properties or to validate CalDAV XML element types. Some of the declarations refer to XML elements defined by WebDAV [RFC2518], which use the "DAV:" namespace. Wherever such XML elements appear, they are explicitly prefixed with "DAV:" to avoid confusion.
Also note that some CalDAV XML element names are identical to WebDAV XML element names, though their namespace differs. Care must be taken not to confuse the two sets of names.
Processing of XML by CalDAV clients and servers MUST follow the rules described in [RFC2518]; in particular, Section 14, and Appendix 3 of that specification.
A "precondition" of a method describes the state of the server that must be true for that method to be performed. A "postcondition" of a method describes the state of the server that must be true after that method has been completed. If a method precondition or postcondition for a request is not satisfied, the response status of the request MUST either be 403 (Forbidden), if the request should not be repeated because it will always fail, or 409 (Conflict), if it is expected that the user might be able to resolve the conflict and resubmit the request.
In order to allow better client handling of 403 and 409 responses, a distinct XML element type is associated with each method precondition and postcondition of a request. When a particular precondition is not satisfied or a particular postcondition cannot be achieved, the appropriate XML element MUST be returned as the child of a top-level DAV:error element in the response body, unless otherwise negotiated by the request.
This section lists what functionality is required of a CalDAV server. To advertise support for CalDAV, a server:
In addition, a server:
One of the features that has made WebDAV a successful protocol is its firm data model. This makes it a useful framework for other applications such as calendaring. This specification follows the same pattern by developing all features based on a well-described data model.
As a brief overview, a CalDAV calendar is modeled as a WebDAV collection with a defined structure; each calendar collection contains a number of resources representing calendar objects as its direct child resource. Each resource representing a calendar object (event, to-do, journal entry, or other calendar components) is called a "calendar object resource". Each calendar object resource and each calendar collection can be individually locked and have individual WebDAV properties. Requirements derived from this model are provided in Section�4.1 and Section�4.2.
A CalDAV server is a calendaring-aware engine combined with a WebDAV repository. A WebDAV repository is a set of WebDAV collections, containing other WebDAV resources, within a unified URL namespace. For example, the repository "http://www.example.com/webdav/" may contain WebDAV collections and resources, all of which have URLs beginning with "http://www.example.com/webdav/". Note that the root URL, "http://www.example.com/", may not itself be a WebDAV repository (for example, if the WebDAV support is implemented through a servlet or other Web server extension).
A WebDAV repository MAY include calendar data in some parts of its URL namespace, and non-calendaring data in other parts.
A WebDAV repository can advertise itself as a CalDAV server if it supports the functionality defined in this specification at any point within the root of the repository. That might mean that calendaring data is spread throughout the repository and mixed with non-calendar data in nearby collections (e.g., calendar data may be found in /home/lisa/calendars/ as well as in /home/bernard/calendars/, and non-calendar data in /home/lisa/contacts/). Or, it might mean that calendar data can be found only in certain sections of the repository (e.g., /calendar/). Calendaring features are only required in the repository sections that are or contain calendar object resources. Therefore, a repository confining calendar data to the /calendar/ collection would only need to support the CalDAV required features within that collection.
The CalDAV server or repository is the canonical location for calendar data and state information. Clients may submit requests to change data or download data. Clients may store calendar objects offline and attempt to synchronize at a later time. However, clients MUST be prepared for calendar data on the server to change between the time of last synchronization and when attempting an update, as calendar collections may be shared and accessible via multiple clients. Entity tags and other features make this possible.
Recurrence is an important part of the data model because it governs how many resources are expected to exist. This specification models a recurring calendar component and its recurrence exceptions as a single resource. In this model, recurrence rules, recurrence dates, exception rules, and exception dates are all part of the data in a single calendar object resource. This model avoids problems of limiting how many recurrence instances to store in the repository, how to keep recurrence instances in sync with the recurring calendar component, and how to link recurrence exceptions with the recurring calendar component. It also results in less data to synchronize between client and server, and makes it easier to make changes to all recurrence instances or to a recurrence rule. It makes it easier to create a recurring calendar component and to delete all recurrence instances.
Clients are not forced to retrieve information about all recurrence instances of a recurring component. The CALDAV:calendar-query and CALDAV:calendar-multiget reports defined in this document allow clients to retrieve only recurrence instances that overlap a given time range.
Calendar object resources contained in calendar collections MUST NOT contain more than one type of calendar component (e.g., VEVENT, VTODO, VJOURNAL, VFREEBUSY, etc.) with the exception of VTIMEZONE components, which MUST be specified for each unique TZID parameter value specified in the iCalendar object. For instance, a calendar object resource can contain one VEVENT component and one VTIMEZONE component, but it cannot contain one VEVENT component and one VTODO component. Instead, the VEVENT and VTODO components would have to be stored in separate calendar object resources in the same collection.
Calendar object resources contained in calendar collections MUST NOT specify the iCalendar METHOD property.
The UID property value of the calendar components contained in a calendar object resource MUST be unique in the scope of the calendar collection in which they are stored.
Calendar components in a calendar collection that have different UID property values MUST be stored in separate calendar object resources.
Calendar components with the same UID property value, in a given calendar collection, MUST be contained in the same calendar object resource. This ensures that all components in a recurrence "set" are contained in the same calendar object resource. It is possible for a calendar object resource to just contain components that represent "overridden" instances (ones that modify the behavior of a regular instance, and thus include a RECURRENCE-ID property) without also including the "master" recurring component (the one that defines the recurrence "set" and does not contain any RECURRENCE-ID property).
For example, given the following iCalendar object:
BEGIN:VCALENDAR PRODID:-//Example Corp.//CalDAV Client//EN VERSION:2.0 BEGIN:VEVENT UID:[email protected] SUMMARY:One-off Meeting DTSTAMP:20041210T183904Z DTSTART:20041207T120000Z DTEND:20041207T130000Z END:VEVENT BEGIN:VEVENT UID:[email protected] SUMMARY:Weekly Meeting DTSTAMP:20041210T183838Z DTSTART:20041206T120000Z DTEND:20041206T130000Z RRULE:FREQ=WEEKLY END:VEVENT BEGIN:VEVENT UID:[email protected] SUMMARY:Weekly Meeting RECURRENCE-ID:20041213T120000Z DTSTAMP:20041210T183838Z DTSTART:20041213T130000Z DTEND:20041213T140000Z END:VEVENT END:VCALENDAR
The VEVENT component with the UID value "[email protected]" would be stored in its own calendar object resource. The two VEVENT components with the UID value "[email protected]", which represent a recurring event where one recurrence instance has been overridden, would be stored in the same calendar object resource.
A calendar collection contains calendar object resources that represent calendar components within a calendar. A calendar collection is manifested to clients as a WebDAV resource collection identified by a URL. A calendar collection MUST report the DAV:collection and CALDAV:calendar XML elements in the value of the DAV:resourcetype property. The element type declaration for CALDAV:calendar is:
<!ELEMENT calendar EMPTY>
A calendar collection can be created through provisioning (i.e., automatically created when a user's account is provisioned), or it can be created with the MKCALENDAR method (see Section�5.3.1). This method can be useful for a user to create additional calendars (e.g., soccer schedule) or for users to share a calendar (e.g., team events or conference rooms). However, note that this document doesn't define the purpose of extra calendar collections. Users must rely on non-standard cues to find out what a calendar collection is for, or use the CALDAV:calendar-description property defined in Section�5.2.1 to provide such a cue.
The following restrictions are applied to the resources within a calendar collection:
Multiple calendar collections MAY be children of the same collection.
A server supporting the features described in this document MUST include "calendar-access" as a field in the DAV response header from an OPTIONS request on any resource that supports any calendar properties, reports, method, or privilege. A value of "calendar-access" in the DAV response header MUST indicate that the server supports all MUST level requirements specified in this document.
>> Request <<
OPTIONS /home/bernard/calendars/ HTTP/1.1 Host: cal.example.com
>> Response <<
HTTP/1.1 200 OK Allow: OPTIONS, GET, HEAD, POST, PUT, DELETE, TRACE, COPY, MOVE Allow: PROPFIND, PROPPATCH, LOCK, UNLOCK, REPORT, ACL DAV: 1, 2, access-control, calendar-access Date: Sat, 11 Nov 2006 09:32:12 GMT Content-Length: 0
In this example, the OPTIONS method returns the value "calendar-access" in the DAV response header to indicate that the collection "/home/bernard/calendars/" supports the properties, reports, method, or privilege defined in this specification.
This section defines properties for calendar collections.
<!ELEMENT calendar-description (#PCDATA)>
PCDATA value: string <C:calendar-description xml:lang="fr-CA"
xmlns:C="urn:ietf:params:xml:ns:caldav"
>Calendrier de Mathilde Desruisseaux</C:calendar-description>
<!ELEMENT calendar-timezone (#PCDATA)>
PCDATA value: an iCalendar object with exactly one VTIMEZONE
component. <C:calendar-timezone
xmlns:C="urn:ietf:params:xml:ns:caldav">BEGIN:VCALENDAR
PRODID:-//Example Corp.//CalDAV Client//EN
VERSION:2.0
BEGIN:VTIMEZONE
TZID:US-Eastern
LAST-MODIFIED:19870101T000000Z
BEGIN:STANDARD
DTSTART:19671029T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:Eastern Standard Time (US & Canada)
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:19870405T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:Eastern Daylight Time (US & Canada)
END:DAYLIGHT
END:VTIMEZONE
END:VCALENDAR
</C:calendar-timezone>
<!ELEMENT supported-calendar-component-set (comp+)>
<C:supported-calendar-component-set
xmlns:C="urn:ietf:params:xml:ns:caldav">
<C:comp name="VEVENT"/>
<C:comp name="VTODO"/>
</C:supported-calendar-component-set>
<!ELEMENT supported-calendar-data (calendar-data+)>
<C:supported-calendar-data
xmlns:C="urn:ietf:params:xml:ns:caldav">
<C:calendar-data content-type="text/calendar" version="2.0"/>
</C:supported-calendar-data>
<!ELEMENT max-resource-size (#PCDATA)>
PCDATA value: a numeric value (positive integer) <C:max-resource-size xmlns:C="urn:ietf:params:xml:ns:caldav"
>102400</C:max-resource-size>
<!ELEMENT min-date-time (#PCDATA)>
PCDATA value: an iCalendar format DATE-TIME value in UTC <C:min-date-time xmlns:C="urn:ietf:params:xml:ns:caldav"
>19000101T000000Z</C:min-date-time>
<!ELEMENT max-date-time (#PCDATA)>
PCDATA value: an iCalendar format DATE-TIME value in UTC <C:max-date-time xmlns:C="urn:ietf:params:xml:ns:caldav"
>20491231T235959Z</C:max-date-time>
<!ELEMENT max-instances (#PCDATA)>
PCDATA value: a numeric value (integer greater than zero) <C:max-instances xmlns:C="urn:ietf:params:xml:ns:caldav"
>100</C:max-instances>
<!ELEMENT max-attendees-per-instance (#PCDATA)>
PCDATA value: a numeric value (integer greater than zero) <C:max-attendees-per-instance
xmlns:C="urn:ietf:params:xml:ns:caldav"
>25</C:max-attendees-per-instance>
This specification requires an additional Precondition for the PROPPATCH method. The precondition is:
Calendar collections and calendar object resources may be created by either a CalDAV client or by the CalDAV server. This specification defines restrictions and a data model that both clients and servers MUST adhere to when manipulating such calendar data.
An HTTP request using the MKCALENDAR method creates a new calendar collection resource. A server MAY restrict calendar collection creation to particular collections.
Support for MKCALENDAR on the server is only RECOMMENDED and not REQUIRED because some calendar stores only support one calendar per user (or principal), and those are typically pre-created for each account. However, servers and clients are strongly encouraged to support MKCALENDAR whenever possible to allow users to create multiple calendar collections to help organize their data better.
Clients SHOULD use the DAV:displayname property for a human-readable name of the calendar. Clients can either specify the value of the DAV:displayname property in the request body of the MKCALENDAR request, or alternatively issue a PROPPATCH request to change the DAV:displayname property to the appropriate value immediately after issuing the MKCALENDAR request. Clients SHOULD NOT set the DAV:displayname property to be the same as any other calendar collection at the same URI "level". When displaying calendar collections to users, clients SHOULD check the DAV:displayname property and use that value as the name of the calendar. In the event that the DAV:displayname property is empty, the client MAY use the last part of the calendar collection URI as the name; however, that path segment may be "opaque" and not represent any meaningful human-readable text.
If a MKCALENDAR request fails, the server state preceding the request MUST be restored.
Marshalling:
<!ELEMENT mkcalendar (DAV:set)>
<!ELEMENT mkcalendar-response ANY>
Preconditions:
Postconditions:
The following are examples of response codes one would expect to get in a response to a MKCALENDAR request. Note that this list is by no means exhaustive.
This example creates a calendar collection called /home/lisa/calendars/events/ on the server cal.example.com with specific values for the properties DAV:displayname, CALDAV:calendar-description, CALDAV:supported-calendar-component-set, and CALDAV:calendar-timezone.
>> Request <<
MKCALENDAR /home/lisa/calendars/events/ HTTP/1.1
Host: cal.example.com
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:mkcalendar xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:set>
<D:prop>
<D:displayname>Lisa's Events</D:displayname>
<C:calendar-description xml:lang="en"
>Calendar restricted to events.</C:calendar-description>
<C:supported-calendar-component-set>
<C:comp name="VEVENT"/>
</C:supported-calendar-component-set>
<C:calendar-timezone><![CDATA[BEGIN:VCALENDAR
PRODID:-//Example Corp.//CalDAV Client//EN
VERSION:2.0
BEGIN:VTIMEZONE
TZID:US-Eastern
LAST-MODIFIED:19870101T000000Z
BEGIN:STANDARD
DTSTART:19671029T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:Eastern Standard Time (US & Canada)
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:19870405T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:Eastern Daylight Time (US & Canada)
END:DAYLIGHT
END:VTIMEZONE
END:VCALENDAR
]]></C:calendar-timezone>
</D:prop>
</D:set>
</C:mkcalendar> >> Response <<
HTTP/1.1 201 Created Cache-Control: no-cache Date: Sat, 11 Nov 2006 09:32:12 GMT Content-Length: 0
Clients populate calendar collections with calendar object resources. The URL for each calendar object resource is entirely arbitrary and does not need to bear a specific relationship to the calendar object resource's iCalendar properties or other metadata. New calendar object resources MUST be created with a PUT request targeted at an unmapped URI. A PUT request targeted at a mapped URI updates an existing calendar object resource.
When servers create new resources, it's not hard for the server to choose an unmapped URI. It's slightly tougher for clients, because a client might not want to examine all resources in the collection and might not want to lock the entire collection to ensure that a new resource isn't created with a name collision. However, there is an HTTP feature to mitigate this. If the client intends to create a new non-collection resource, such as a new VEVENT, the client SHOULD use the HTTP request header "If-None-Match: *" on the PUT request. The Request-URI on the PUT request MUST include the target collection, where the resource is to be created, plus the name of the resource in the last path segment. The "If-None-Match: *" request header ensures that the client will not inadvertently overwrite an existing resource if the last path segment turned out to already be used.
>> Request <<
PUT /home/lisa/calendars/events/qwue23489.ics HTTP/1.1 If-None-Match: * Host: cal.example.com Content-Type: text/calendar Content-Length: xxxx BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Example Corp.//CalDAV Client//EN BEGIN:VEVENT UID:[email protected] DTSTAMP:20060712T182145Z DTSTART:20060714T170000Z DTEND:20060715T040000Z SUMMARY:Bastille Day Party END:VEVENT END:VCALENDAR
>> Response <<
HTTP/1.1 201 Created Content-Length: 0 Date: Sat, 11 Nov 2006 09:32:12 GMT ETag: "123456789-000-111"
The request to change an existing event is the same, but with a specific ETag in the "If-Match" header, rather than the "If-None-Match" header.
As indicated in Section 3.10 of [RFC2445], the URL of calendar object resources containing (an arbitrary set of) calendaring and scheduling information may be suffixed by ".ics", and the URL of calendar object resources containing free or busy time information may be suffixed by ".ifb".
This specification creates additional Preconditions for PUT, COPY, and MOVE methods. These preconditions apply when a PUT operation of a calendar object resource into a calendar collection occurs, or when a COPY or MOVE operation of a calendar object resource into a calendar collection occurs, or when a COPY or MOVE operation occurs on a calendar collection.
The new preconditions are:
<!ELEMENT no-uid-conflict (DAV:href)>
iCalendar provides a "standard mechanism for doing non-standard things". This extension support allows implementers to make use of non-standard components, properties, and parameters whose names are prefixed with the text "X-".
Servers MUST support the use of non-standard components, properties, and parameters in calendar object resources stored via the PUT method.
Servers may need to enforce rules for their own "private" components, properties, or parameters, so servers MAY reject any attempt by the client to change those or use values for those outside of any restrictions the server may have. Servers SHOULD ensure that any "private" components, properties, or parameters it uses follow the convention of including a vendor id in the "X-" name, as described in Section 4.2 of [RFC2445], e.g., "X-ABC-PRIVATE".
The DAV:getetag property MUST be defined and set to a strong entity tag on all calendar object resources.
A response to a GET request targeted at a calendar object resource MUST contain an ETag response header field indicating the current value of the strong entity tag of the calendar object resource.
Servers SHOULD return a strong entity tag (ETag header) in a PUT response when the stored calendar object resource is equivalent by octet equality to the calendar object resource submitted in the body of the PUT request. This allows clients to reliably use the returned strong entity tag for data synchronization purposes. For instance, the client can do a PROPFIND request on the stored calendar object resource and have the DAV:getetag property returned, and compare that value with the strong entity tag it received on the PUT response, and know that if they are equal, then the calendar object resource on the server has not been changed.
In the case where the data stored by a server as a result of a PUT request is not equivalent by octet equality to the submitted calendar object resource, the behavior of the ETag response header is not specified here, with the exception that a strong entity tag MUST NOT be returned in the response. As a result, clients may need to retrieve the modified calendar object resource (and ETag) as a basis for further changes, rather than use the calendar object resource it had sent with the PUT request.
CalDAV servers MUST support and adhere to the requirements of WebDAV ACL [RFC3744]. WebDAV ACL provides a framework for an extensible set of privileges that can be applied to WebDAV collections and ordinary resources. CalDAV servers MUST also support the calendaring privilege defined in this section.
Calendar users often wish to allow other users to see their busy time information, without viewing the other details of the calendar components (e.g., location, summary, attendees). This allows a significant amount of privacy while still allowing other users to schedule meetings at times when the user is likely to be free.
The CALDAV:read-free-busy privilege controls which calendar collections, regular collections, and calendar object resources are examined when a CALDAV:free-busy-query REPORT request is processed (see Section�7.10). This privilege can be granted on calendar collections, regular collections, or calendar object resources. Servers MUST support this privilege on all calendar collections, regular collections, and calendar object resources.
<!ELEMENT read-free-busy EMPTY>
The CALDAV:read-free-busy privilege MUST be aggregated in the DAV:read privilege. Servers MUST allow the CALDAV:read-free-busy to be granted without the DAV:read privilege being granted.
Clients should note that when only the CALDAV:read-free-busy privilege has been granted on a resource, access to GET, HEAD, OPTIONS, and PROPFIND on the resource is not implied (those operations are governed by the DAV:read privilege).
This section defines an additional property for WebDAV principal resources, as defined in [RFC3744].
<!ELEMENT calendar-home-set (DAV:href*)>
<C:calendar-home-set xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:href>http://cal.example.com/home/bernard/calendars/</D:href>
</C:calendar-home-set>
This section defines the reports that CalDAV servers MUST support on calendar collections and calendar object resources.
CalDAV servers MUST advertise support for these reports on all calendar collections and calendar object resources with the DAV:supported-report-set property, defined in Section 3.1.5 of [RFC3253]. CalDAV servers MAY also advertise support for these reports on ordinary collections.
Some of these reports allow calendar data (from possibly multiple resources) to be returned.
The REPORT method (defined in Section 3.6 of [RFC3253]) provides an extensible mechanism for obtaining information about one or more resources. Unlike the PROPFIND method, which returns the value of one or more named properties, the REPORT method can involve more complex processing. REPORT is valuable in cases where the server has access to all of the information needed to perform the complex request (such as a query), and where it would require multiple requests for the client to retrieve the information needed to perform the same request.
CalDAV servers MUST support the DAV:expand-property REPORT defined in Section 3.8 of [RFC3253].
Servers MAY support the reports defined in this document on ordinary collections (collections that are not calendar collections), in addition to calendar collections or calendar object resources. In computing responses to the reports on ordinary collections, servers MUST only consider calendar object resources contained in calendar collections that are targeted by the REPORT request, based on the value of the Depth request header.
iCalendar provides a way to specify DATE and DATE-TIME values that are not bound to any time zone in particular, hereafter called "floating date" and "floating time", respectively. These values are used to represent the same day, hour, minute, and second value, regardless of which time zone is being observed. For instance, the DATE value "20051111", represents November 11, 2005 in no specific time zone, while the DATE-TIME value "20051111T111100" represents November 11, 2005, at 11:11 A.M. in no specific time zone.
CalDAV servers may need to convert "floating date" and "floating time" values in date with UTC time values in the processing of calendaring REPORT requests.
For the CALDAV:calendar-query REPORT, CalDAV servers MUST rely on the value of the CALDAV:timezone XML element, if specified as part of the request body, to perform the proper conversion of "floating date" and "floating time" values to date with UTC time values. If the CALDAV:timezone XML element is not specified in the request body, CalDAV servers MUST rely on the value of the CALDAV:calendar-timezone property, if defined, or else the CalDAV servers MAY rely on the time zone of their choice.
For the CALDAV:free-busy-query REPORT, CalDAV servers MUST rely on the value of the CALDAV:calendar-timezone property, if defined, to compute the proper FREEBUSY time period value as date with UTC time for calendar components scheduled with "floating date" or "floating time". If the CALDAV:calendar-timezone property is not defined, CalDAV servers MAY rely on the time zone of their choice.
Some of the reports defined in this section can include a time range filter that is used to restrict the set of calendar object resources returned to just those that overlap the specified time range. The time range filter can be applied to a calendar component as a whole, or to specific calendar component properties with DATE or DATE-TIME value types.
To determine whether a calendar object resource matches the time range filter element, the start and end times for the targeted component or property are determined and then compared to the requested time range. If there is an overlap with the requested time range, then the calendar object resource matches the filter element. The rules defined in [RFC2445] for determining the actual start and end times of calendar components MUST be used, and these are fully enumerated in Section�9.9 of this document.
When such time range filtering is used, special consideration must be given to recurring calendar components, such as VEVENT and VTODO. The server MUST expand recurring components to determine whether any recurrence instances overlap the specified time range. If one or more recurrence instances overlap the time range, then the calendar object resource matches the filter element.
Some of the reports defined in this section do text matches of character strings provided by the client and are compared to stored calendar data. Since iCalendar data is, by default, encoded in the UTF-8 charset and may include characters outside the US-ASCII charset range in some property and parameter values, there is a need to ensure that text matching follows well-defined rules.
To deal with this, this specification makes use of the IANA Collation Registry defined in [RFC4790] to specify collations that may be used to carry out the text comparison operations with a well-defined rule.
The comparisons used in CalDAV are all "substring" matches, as per [RFC4790], Section 4.2. Collations supported by the server MUST support "substring" match operations.
CalDAV servers are REQUIRED to support the "i;ascii-casemap" and "i;octet" collations, as described in [RFC4790], and MAY support other collations.
Servers MUST advertise the set of collations that they support via the CALDAV:supported-collation-set property defined on any resource that supports reports that use collations.
Clients MUST only use collations from the list advertised by the server.
In the absence of a collation explicitly specified by the client, or if the client specifies the "default" collation identifier (as defined in [RFC4790], Section 3.1), the server MUST default to using "i;ascii-casemap" as the collation.
Wildcards (as defined in [RFC4790], Section 3.2) MUST NOT be used in the collation identifier.
If the client chooses a collation not supported by the server, the server MUST respond with a CALDAV:supported-collation precondition error response.
<!ELEMENT supported-collation-set (supported-collation*)>
<!ELEMENT supported-collation (#PCDATA)> <C:supported-collation-set
xmlns:C="urn:ietf:params:xml:ns:caldav">
<C:supported-collation>i;ascii-casemap</C:supported-collation>
<C:supported-collation>i;octet</C:supported-collation>
</C:supported-collation-set>
Some calendaring reports defined in this document allow partial retrieval of calendar object resources. A CalDAV client can specify what information to return in the body of a calendaring REPORT request.
A CalDAV client can request particular WebDAV property values, all WebDAV property values, or a list of the names of the resource's WebDAV properties. A CalDAV client can also request calendar data to be returned and specify whether all calendar components and properties should be returned, or only particular ones. See CALDAV:calendar-data in Section�9.6.
By default, the returned calendar data will include the component that defines the recurrence set, referred to as the "master component", as well as the components that define exceptions to the recurrence set, referred to as the "overridden components".
A CalDAV client that is only interested in the recurrence instances that overlap a specified time range can request to receive only the "master component", along with the "overridden components" that impact the specified time range, and thus, limit the data returned by the server (see CALDAV:limit-recurrence-set in Section�9.6.6). An overridden component impacts a time range if its current start and end times overlap the time range, or if the original start and end times -- the ones that would have been used if the instance were not overridden -- overlap the time range, or if it affects other instances that overlap the time range.
A CalDAV client with no support for recurrence properties (i.e., EXDATE, EXRULE, RDATE, and RRULE) and possibly VTIMEZONE components, or a client unwilling to perform recurrence expansion because of limited processing capability, can request to receive only the recurrence instances that overlap a specified time range as separate calendar components that each define exactly one recurrence instance (see CALDAV:expand in Section�9.6.5.)
Finally, in the case of VFREEBUSY components, a CalDAV client can request to receive only the FREEBUSY property values that overlap a specified time range (see CALDAV:limit-freebusy-set in Section�9.6.7.)
Servers MUST support the use of non-standard component, property, or parameter names in the CALDAV:calendar-data XML element in calendaring REPORT requests to allow clients to request that non-standard components, properties, and parameters be returned in the calendar data provided in the response.
Servers MAY support the use of non-standard component, property, or parameter names in the CALDAV:comp-filter, CALDAV:prop-filter, and CALDAV:param-filter XML elements specified in the CALDAV:filter XML element of calendaring REPORT requests.
Servers MUST fail with the CALDAV:supported-filter precondition if a calendaring REPORT request uses a CALDAV:comp-filter, CALDAV:prop-filter, or CALDAV:param-filter XML element that makes reference to a non-standard component, property, or parameter name on which the server does not support queries.
The CALDAV:calendar-query REPORT performs a search for all calendar object resources that match a specified filter. The response of this report will contain all the WebDAV properties and calendar object resource data specified in the request. In the case of the CALDAV:calendar-data XML element, one can explicitly specify the calendar components and properties that should be returned in the calendar object resource data that matches the filter.
The format of this report is modeled on the PROPFIND method. The request and response bodies of the CALDAV:calendar-query REPORT use XML elements that are also used by PROPFIND. In particular, the request can include XML elements to request WebDAV properties to be returned. When that occurs, the response should follow the same behavior as PROPFIND with respect to the DAV:multistatus response elements used to return specific property results. For instance, a request to retrieve the value of a property that does not exist is an error and MUST be noted with a response XML element that contains a 404 (Not Found) status value.
Support for the CALDAV:calendar-query REPORT is REQUIRED.
Marshalling:
Preconditions:
<!ELEMENT supported-filter (comp-filter*,
prop-filter*,
param-filter*)>
Postconditions:
In this example, the client requests the server to return specific components and properties of the VEVENT components that overlap the time range from January 4, 2006, at 00:00:00 A.M. UTC to January 5, 2006, at 00:00:00 A.M. UTC. In addition, the DAV:getetag property is also requested and returned as part of the response. Note that the first calendar object returned is a recurring event whose first instance lies outside the requested time range, but whose third instance does overlap the time range. Note that due to the CALDAV:calendar-data element restrictions, the DTSTAMP property in VEVENT components has not been returned, and the only property returned in the VCALENDAR object is VERSION.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop>
<D:getetag/>
<C:calendar-data>
<C:comp name="VCALENDAR">
<C:prop name="VERSION"/>
<C:comp name="VEVENT">
<C:prop name="SUMMARY"/>
<C:prop name="UID"/>
<C:prop name="DTSTART"/>
<C:prop name="DTEND"/>
<C:prop name="DURATION"/>
<C:prop name="RRULE"/>
<C:prop name="RDATE"/>
<C:prop name="EXRULE"/>
<C:prop name="EXDATE"/>
<C:prop name="RECURRENCE-ID"/>
</C:comp>
<C:comp name="VTIMEZONE"/>
</C:comp>
</C:calendar-data>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VEVENT">
<C:time-range start="20060104T000000Z"
end="20060105T000000Z"/>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd2.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd2"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=US/Eastern:20060102T120000
DURATION:PT1H
RRULE:FREQ=DAILY;COUNT=5
SUMMARY:Event #2
UID:[email protected]
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=US/Eastern:20060104T140000
DURATION:PT1H
RECURRENCE-ID;TZID=US/Eastern:20060104T120000
SUMMARY:Event #2 bis
UID:[email protected]
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=US/Eastern:20060106T140000
DURATION:PT1H
RECURRENCE-ID;TZID=US/Eastern:20060106T120000
SUMMARY:Event #2 bis bis
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd3.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd3"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=US/Eastern:20060104T100000
DURATION:PT1H
SUMMARY:Event #3
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return VEVENT components that overlap the time range from January 3, 2006, at 00:00:00 A.M. UTC to January 5, 2006, at 00:00:00 A.M. UTC. Use of the CALDAV:limit-recurrence-set element causes the server to only return overridden recurrence components that overlap the time range specified in that element or that affect other instances that overlap the time range (e.g., in the case of a THISANDFUTURE behavior). In this example, the first overridden component in the matching resource is returned, but the second one is not.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop>
<C:calendar-data>
<C:limit-recurrence-set start="20060103T000000Z"
end="20060105T000000Z"/>
</C:calendar-data>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VEVENT">
<C:time-range start="20060103T000000Z"
end="20060105T000000Z"/>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd2.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd2"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART;TZID=US/Eastern:20060102T120000
DURATION:PT1H
RRULE:FREQ=DAILY;COUNT=5
SUMMARY:Event #2
UID:[email protected]
END:VEVENT
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART;TZID=US/Eastern:20060104T140000
DURATION:PT1H
RECURRENCE-ID;TZID=US/Eastern:20060104T120000
SUMMARY:Event #2 bis
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd3.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd3"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
ATTENDEE;PARTSTAT=ACCEPTED;ROLE=CHAIR:mailto:[email protected]
ATTENDEE;PARTSTAT=NEEDS-ACTION:mailto:[email protected]
DTSTAMP:20060206T001220Z
DTSTART;TZID=US/Eastern:20060104T100000
DURATION:PT1H
LAST-MODIFIED:20060206T001330Z
ORGANIZER:mailto:[email protected]
SEQUENCE:1
STATUS:TENTATIVE
SUMMARY:Event #3
UID:[email protected]
X-ABC-GUID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return VEVENT components that overlap the time range from January 2, 2006, at 00:00:00 A.M. UTC to January 5, 2006, at 00:00:00 A.M. UTC and to return recurring calendar components expanded into individual recurrence instance calendar components. Use of the CALDAV:expand element causes the server to only return overridden recurrence instances that overlap the time range specified in that element.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop>
<C:calendar-data>
<C:expand start="20060103T000000Z"
end="20060105T000000Z"/>
</C:calendar-data>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VEVENT">
<C:time-range start="20060103T000000Z"
end="20060105T000000Z"/>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd2.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd2"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART:20060103T170000
DURATION:PT1H
RECURRENCE-ID:20060103T170000
SUMMARY:Event #2
UID:[email protected]
END:VEVENT
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART:20060104T190000
DURATION:PT1H
RECURRENCE-ID:20060104T170000
SUMMARY:Event #2 bis
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd3.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd3"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VEVENT
ATTENDEE;PARTSTAT=ACCEPTED;ROLE=CHAIR:mailto:[email protected]
ATTENDEE;PARTSTAT=NEEDS-ACTION:mailto:[email protected]
DTSTAMP:20060206T001220Z
DTSTART:20060104T150000
DURATION:PT1H
LAST-MODIFIED:20060206T001330Z
ORGANIZER:mailto:[email protected]
SEQUENCE:1
STATUS:TENTATIVE
SUMMARY:Event #3
UID:[email protected]
X-ABC-GUID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return the VFREEBUSY components that have free busy information that overlap the time range from January 2, 2006, at 00:00:00 A.M. UTC (inclusively) to January 3, 2006, at 00:00:00 A.M. UTC (exclusively). Use of the CALDAV:limit-freebusy-set element causes the server to only return the FREEBUSY property values that overlap the time range specified in that element. Note that this is not an example of discovering when the calendar owner is busy.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop>
<C:calendar-data>
<C:limit-freebusy-set start="20060102T000000Z"
end="20060103T000000Z"/>
</C:calendar-data>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VFREEBUSY">
<C:time-range start="20060102T000000Z"
end="20060103T000000Z"/>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd8.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd8"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VFREEBUSY
ORGANIZER;CN="Bernard Desruisseaux":mailto:[email protected]
UID:[email protected]
DTSTAMP:20050530T123421Z
DTSTART:20060101T100000Z
DTEND:20060108T100000Z
FREEBUSY;FBTYPE=BUSY-TENTATIVE:20060102T100000Z/20060102T120000Z
END:VFREEBUSY
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return the VTODO components that have an alarm trigger scheduled in the specified time range.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop xmlns:D="DAV:">
<D:getetag/>
<C:calendar-data/>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VTODO">
<C:comp-filter name="VALARM">
<C:time-range start="20060106T100000Z"
end="20060107T100000Z"/>
</C:comp-filter>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd4.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd4"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTODO
DTSTAMP:20060205T235300Z
DUE;TZID=US/Eastern:20060106T120000
LAST-MODIFIED:20060205T235308Z
SEQUENCE:1
STATUS:NEEDS-ACTION
SUMMARY:Task #2
UID:[email protected]
BEGIN:VALARM
ACTION:AUDIO
TRIGGER;RELATED=START:-PT10M
END:VALARM
END:VTODO
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return the VEVENT component that has the UID property set to "[email protected]".
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop xmlns:D="DAV:">
<D:getetag/>
<C:calendar-data/>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VEVENT">
<C:prop-filter name="UID">
<C:text-match collation="i;octet"
>[email protected]</C:text-match>
</C:prop-filter>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd3.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd3"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
ATTENDEE;PARTSTAT=ACCEPTED;ROLE=CHAIR:mailto:[email protected]
ATTENDEE;PARTSTAT=NEEDS-ACTION:mailto:[email protected]
DTSTAMP:20060206T001220Z
DTSTART;TZID=US/Eastern:20060104T100000
DURATION:PT1H
LAST-MODIFIED:20060206T001330Z
ORGANIZER:mailto:[email protected]
SEQUENCE:1
STATUS:TENTATIVE
SUMMARY:Event #3
UID:[email protected]
X-ABC-GUID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return the VEVENT components that have the ATTENDEE property with the value "mailto:[email protected]" and for which the PARTSTAT parameter is set to NEEDS-ACTION.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop xmlns:D="DAV:">
<D:getetag/>
<C:calendar-data/>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VEVENT">
<C:prop-filter name="ATTENDEE">
<C:text-match collation="i;ascii-casemap"
>mailto:[email protected]</C:text-match>
<C:param-filter name="PARTSTAT">
<C:text-match collation="i;ascii-casemap"
>NEEDS-ACTION</C:text-match>
</C:param-filter>
</C:prop-filter>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd3.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd3"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
ATTENDEE;PARTSTAT=ACCEPTED;ROLE=CHAIR:mailto:[email protected]
ATTENDEE;PARTSTAT=NEEDS-ACTION:mailto:[email protected]
DTSTAMP:20060206T001220Z
DTSTART;TZID=US/Eastern:20060104T100000
DURATION:PT1H
LAST-MODIFIED:20060206T001330Z
ORGANIZER:mailto:[email protected]
SEQUENCE:1
STATUS:TENTATIVE
SUMMARY:Event #3
UID:[email protected]
X-ABC-GUID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return all VEVENT components.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop xmlns:D="DAV:">
<D:getetag/>
<C:calendar-data/>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VEVENT"/>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd1.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd1"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20060206T001102Z
DTSTART;TZID=US/Eastern:20060102T100000
DURATION:PT1H
SUMMARY:Event #1
Description:Go Steelers!
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd2.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd2"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART;TZID=US/Eastern:20060102T120000
DURATION:PT1H
RRULE:FREQ=DAILY;COUNT=5
SUMMARY:Event #2
UID:[email protected]
END:VEVENT
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART;TZID=US/Eastern:20060104T140000
DURATION:PT1H
RECURRENCE-ID;TZID=US/Eastern:20060104T120000
SUMMARY:Event #2 bis
UID:[email protected]
END:VEVENT
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART;TZID=US/Eastern:20060106T140000
DURATION:PT1H
RECURRENCE-ID;TZID=US/Eastern:20060106T120000
SUMMARY:Event #2 bis bis
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd3.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd3"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
ATTENDEE;PARTSTAT=ACCEPTED;ROLE=CHAIR:mailto:[email protected]
ATTENDEE;PARTSTAT=NEEDS-ACTION:mailto:[email protected]
DTSTAMP:20060206T001220Z
DTSTART;TZID=US/Eastern:20060104T100000
DURATION:PT1H
LAST-MODIFIED:20060206T001330Z
ORGANIZER:mailto:[email protected]
SEQUENCE:1
STATUS:TENTATIVE
SUMMARY:Event #3
UID:[email protected]
X-ABC-GUID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return all VTODO components that do not include a COMPLETED property and do not have a STATUS property value matching CANCELLED, i.e., VTODOs that still need to be worked on.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop xmlns:D="DAV:">
<D:getetag/>
<C:calendar-data/>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VTODO">
<C:prop-filter name="COMPLETED">
<C:is-not-defined/>
</C:prop-filter>
<C:prop-filter name="STATUS">
<C:text-match
negate-condition="yes">CANCELLED</C:text-match>
</C:prop-filter>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd4.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd4"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTODO
DTSTAMP:20060205T235335Z
DUE;VALUE=DATE:20060104
STATUS:NEEDS-ACTION
SUMMARY:Task #1
UID:[email protected]
BEGIN:VALARM
ACTION:AUDIO
TRIGGER;RELATED=START:-PT10M
END:VALARM
END:VTODO
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd5.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd5"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTODO
DTSTAMP:20060205T235300Z
DUE;VALUE=DATE:20060106
LAST-MODIFIED:20060205T235308Z
SEQUENCE:1
STATUS:NEEDS-ACTION
SUMMARY:Task #2
UID:[email protected]
BEGIN:VALARM
ACTION:AUDIO
TRIGGER;RELATED=START:-PT10M
END:VALARM
END:VTODO
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> In this example, the client requests the server to return all VEVENT components that include an X-ABC-GUID property with a value matching "ABC". However, the server does not support querying that non-standard property, and instead returns an error response.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop xmlns:D="DAV:">
<D:getetag/>
<C:calendar-data/>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VEVENT">
<C:prop-filter name="X-ABC-GUID">
<C:text-match>ABC</C:text-match>
</C:prop-filter>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> >> Response <<
HTTP/1.1 403 Forbidden
Date: Sat, 11 Nov 2005 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:error>
<C:supported-filter>
<C:prop-filter name="X-ABC-GUID"/>
</C:supported-filter>
</D:error> The CALDAV:calendar-multiget REPORT is used to retrieve specific calendar object resources from within a collection, if the Request-URI is a collection, or to retrieve a specific calendar object resource, if the Request-URI is a calendar object resource. This report is similar to the CALDAV:calendar-query REPORT (see Section�7.8), except that it takes a list of DAV:href elements, instead of a CALDAV:filter element, to determine which calendar object resources to return.
Support for the CALDAV:calendar-multiget REPORT is REQUIRED.
Marshalling:
Preconditions:
Postconditions:
In this example, the client requests the server to return specific properties of the VEVENT components referenced by specific URIs. In addition, the DAV:getetag property is also requested and returned as part of the response. Note that in this example, the resource at http://cal.example.com/bernard/work/mtg1.ics does not exist, resulting in an error status response.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-multiget xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop>
<D:getetag/>
<C:calendar-data/>
</D:prop>
<D:href>/bernard/work/abcd1.ics</D:href>
<D:href>/bernard/work/mtg1.ics</D:href>
</C:calendar-multiget> >> Response <<
HTTP/1.1 207 Multi-Status
Date: Sat, 11 Nov 2006 09:32:12 GMT
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd1.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd1"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20060206T001102Z
DTSTART;TZID=US/Eastern:20060102T100000
DURATION:PT1H
SUMMARY:Event #1
Description:Go Steelers!
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/mtg1.ics</D:href>
<D:status>HTTP/1.1 404 Not Found</D:status>
</D:response>
</D:multistatus> The CALDAV:free-busy-query REPORT generates a VFREEBUSY component containing free busy information for all the calendar object resources targeted by the request and that have the CALDAV:read-free-busy or DAV:read privilege granted to the current user.
Only VEVENT components without a TRANSP property or with the TRANSP property set to OPAQUE, and VFREEBUSY components SHOULD be considered in generating the free busy time information.
In the case of VEVENT components, the free or busy time type (FBTYPE) of the FREEBUSY properties in the returned VFREEBUSY component SHOULD be derived from the value of the TRANSP and STATUS properties, as outlined in the table below:
+---------------------------++------------------+
| VEVENT || VFREEBUSY |
+-------------+-------------++------------------+
| TRANSP | STATUS || FBTYPE |
+=============+=============++==================+
| | CONFIRMED || BUSY |
| | (default) || |
| OPAQUE +-------------++------------------+
| (default) | CANCELLED || FREE |
| +-------------++------------------+
| | TENTATIVE || BUSY-TENTATIVE |
| +-------------++------------------+
| | x-name || BUSY or |
| | || x-name |
+-------------+-------------++------------------+
| | CONFIRMED || |
| TRANSPARENT | CANCELLED || FREE |
| | TENTATIVE || |
| | x-name || |
+-------------+-------------++------------------+
Duplicate busy time periods with the same FBTYPE parameter value SHOULD NOT be specified in the returned VFREEBUSY component. Servers SHOULD coalesce consecutive or overlapping busy time periods of the same type. Busy time periods with different FBTYPE parameter values MAY overlap.
Support for the CALDAV:free-busy-query REPORT is REQUIRED.
Marshalling:
Preconditions:
Postconditions:
In this example, the client requests the server to return free busy information on the calendar collection /bernard/work/, between 9:00 A.M. and 5:00 P.M. EST (2:00 P.M. and 10:00 P.M. UTC) on the January 4, 2006. The server responds, indicating two busy time intervals of one hour, one of which is tentative.
See Appendix�B for the calendar data being targeted by this example.
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:free-busy-query xmlns:C="urn:ietf:params:xml:ns:caldav">
<C:time-range start="20060104T140000Z"
end="20060105T220000Z"/>
</C:free-busy-query> >> Response <<
HTTP/1.1 200 OK Date: Sat, 11 Nov 2006 09:32:12 GMT Content-Type: text/calendar Content-Length: xxxx BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Example Corp.//CalDAV Server//EN BEGIN:VFREEBUSY DTSTAMP:20050125T090000Z DTSTART:20060104T140000Z DTEND:20060105T220000Z FREEBUSY;FBTYPE=BUSY-TENTATIVE:20060104T150000Z/PT1H FREEBUSY:20060104T190000Z/PT1H END:VFREEBUSY END:VCALENDAR
There are a number of actions clients can take that will be legal (the server will not return errors), but that can degrade interoperability with other client implementations accessing the same data. For example, a recurrence rule could be replaced with a set of recurrence dates, a single recurring event could be replaced with a set of independent resources to represent each recurrence, or the start/end time values can be translated from the original time zone to another time zone. Although this advice amounts to iCalendar interoperability best practices and is not limited only to CalDAV usage, interoperability problems are likely to be more evident in CalDAV use cases.
WebDAV already provides functionality required to synchronize a collection or set of collections, to make changes offline, and provides a simple way to resolve conflicts when reconnected. ETags are the key to making this work, but these are not required of all WebDAV servers. Since offline functionality is more important to calendar applications than to some other WebDAV applications, CalDAV servers MUST support ETags, as specified in Section�5.3.4.
The reports provided in CalDAV can be used by clients to optimize their performance in terms of network bandwidth usage and resource consumption on the local client machine. Both are certainly major considerations for mobile or handheld devices with limited capacity, but they are also relevant to desktop client applications in cases where the calendar collections contain large amounts of data.
Typically, clients present calendar data to users in views that span a finite time interval, so whenever possible, clients should only retrieve calendar components from the server using CALDAV:calendar-query REPORT, combined with a CALDAV:time-range element, to limit the set of returned components to just those needed to populate the current view.
Typically in a calendar, historical data (events, to-dos, etc. that have completed prior to the current date) do not change, though they may be deleted. As a result, a client can speed up the synchronization process by only considering data for the present time and the future up to a reasonable limit (e.g., one week, one month). If the user then tries to examine a portion of the calendar outside the range that has been synchronized, the client can perform another synchronization operation on the new time interval being examined. This "just-in-time" synchronization can minimize bandwidth for common user interaction behaviors.
If a client wants to support calendar data synchronization, as opposed to downloading calendar data each time it is needed, the client needs to cache the calendar object resource's URI and ETag, along with the actual calendar data. While the URI remains static for the lifetime of the calendar object resource, the ETag will change with each successive change to the calendar object resource. Thus, to synchronize a local data cache with the server, the client can first fetch the URI/ETag pairs for the time interval being considered, and compare those results with the cached data. Any cached component whose ETag differs from that on the server needs to be refreshed.
In order to properly detect the changes between the server and client data, the client will need to keep a record of which calendar object resources have been created, changed, or deleted since the last synchronization operation so that it can reconcile those changes with the data on the server.
Here's an example of how to do that:
The client issues a CALDAV:calendar-query REPORT request for a specific time range and asks for only the DAV:getetag property to be returned:
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop>
<D:getetag/>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR">
<C:comp-filter name="VEVENT">
<C:time-range start="20040902T000000Z"
end="20040903T000000Z"/>
</C:comp-filter>
</C:comp-filter>
</C:filter>
</C:calendar-query> The client then uses the results to determine which calendar object resources have changed, been created, or deleted on the server, and how those relate to locally cached calendar object resources that may have changed, been created, or deleted. If the client determines that there are calendar object resources on the server that need to be fetched, the client issues a CALDAV:calendar-multiget REPORT request to fetch its calendar data:
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-multiget xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop>
<D:getetag/>
<C:calendar-data/>
</D:prop>
<D:href>/bernard/work/abcd1.ics</D:href>
<D:href>/bernard/work/mtg1.ics</D:href>
</C:calendar-multiget> A client may not need all the calendar properties of a calendar object resource when presenting information to the user. Since some calendar property values can be large (e.g., ATTACH or ATTENDEE), a client can choose to restrict the calendar properties to be returned in a calendaring REPORT request to those it knows it will use.
However, if a client needs to make a change to a calendar object resource, it can only change the entire calendar object resource via a PUT request. There is currently no way to incrementally make a change to a set of calendar properties of a calendar object resource. As a result, the client will have to get the entire calendar object resource that is being changed.
WebDAV locks can be used to prevent two clients that are modifying the same resource from either overwriting each others' changes (though that problem can also be solved by using ETags) or wasting time making changes that will conflict with another set of changes. In a multi-user calendar system, an interactive calendar client could lock an event while the user is editing the event, and unlock the event when the user finishes or cancels. Locks can also be used to prevent changes while data is being reorganized. For example, a calendar client might lock two calendar collections prior to moving a bunch of calendar resources from one to another.
Clients are responsible for requesting a lock timeout period that is appropriate to the use case. When the user explicitly decides to reserve a resource and prevent other changes, a long timeout might be appropriate, but in cases where the client automatically decides to lock the resource, the timeout should be short (and the client can always refresh the lock should it need to). A short lock timeout means that if the client is unable to remove the lock, the other calendar users aren't prevented from making changes.
Much of the time, a calendar client (or agent) will discover a new calendar's location by being provided directly with the URL. For example, a user will type his or her own calendar location into client configuration information or copy and paste a URL from email into the calendar application. The client need only confirm that the URL points to a resource that is a calendar collection. The client may also be able to browse WebDAV collections to find calendar collections.
The choice of HTTP URLs means that calendar object resources are backward compatible with existing software, but does have the disadvantage that existing software does not usually know to look at the OPTIONS response to that URL to determine what can be done with it. This is somewhat of a barrier for WebDAV usage as well as with CalDAV usage. This specification does not offer a way through this other than making the information available in the OPTIONS response should this be requested.
For calendar sharing and scheduling use cases, one might wish to find the calendar belonging to another user. If the other user has a calendar in the same repository, that calendar can be found by using the principal namespace required by WebDAV ACL support. For other cases, the authors have no universal solution, but implementers can consider whether to use vCard [RFC2426] or LDAP [RFC4511] standards together with calendar attributes [RFC2739].
Because CalDAV requires servers to support WebDAV ACL [RFC3744], including principal namespaces, and with the addition of the CALDAV:calendar-home-set property, there are a couple options for CalDAV clients to find one's own calendar or another user's calendar.
In this case, a DAV:principal-match REPORT is used to find a named property (the CALDAV:calendar-home-set) on the Principal-URL of the current user. Using this, a WebDAV client can learn "who am I" and "where are my calendars". The REPORT request body looks like this:
<?xml version="1.0" encoding="utf-8" ?>
<D:principal-match xmlns:D="DAV:">
<D:self/>
<D:prop>
<C:calendar-home-set
xmlns:C="urn:ietf:params:xml:ns:caldav"/>
</D:prop>
</D:principal-match> To find other users' calendars, the DAV:principal-property-search REPORT can be used to filter on some properties and return others. To search for a calendar owned by a user named "Laurie", the REPORT request body would look like this:
<?xml version="1.0" encoding="utf-8" ?>
<D:principal-property-search xmlns:D="DAV:">
<D:property-search>
<D:prop>
<D:displayname/>
</D:prop>
<D:match>Laurie</D:match>
</D:property-search>
<D:prop>
<C:calendar-home-set
xmlns:C="urn:ietf:params:xml:ns:caldav"/>
<D:displayname/>
</D:prop>
</D:principal-property-search> The server performs a case-sensitive or caseless search for a matching string subset of "Laurie" within the DAV:displayname property. Thus, the server might return "Laurie Dusseault", "Laurier Desruisseaux", or "Wilfrid Laurier" as matching DAV:displayname values, and return the calendars for each of these.
CalDAV clients MAY create attachments in calendar components either as inline or external. This section contains some guidelines for creating and managing attachments.
CalDAV clients MUST support inline attachments as specified in iCalendar [RFC2445]. CalDAV servers MUST support inline attachments, so clients can rely on being able to create attachments this way. On the other hand, inline attachments have some drawbacks:
CalDAV clients SHOULD support downloading of external attachments referenced by arbitrary URI schemes, by either processing them directly, or by passing the attachment URI to a suitable "helper application" for processing, if such an application exists. CalDAV clients MUST support downloading of external attachments referenced by the "http" or "https" URI schemes. An external attachment could be:
CalDAV servers MAY provide support for child collections in calendar collections. CalDAV servers MAY allow the MKCOL method to create child collections in calendar collections. Child collections of calendar collections MAY contain any type of resource except calendar collections that they MUST NOT contain. Some CalDAV servers won't allow child collections in calendar collections, and it may be possible on such a server to discover other locations where attachments can be stored.
Clients are entirely responsible for maintaining reference consistency with calendar components that link to external attachments. A client deleting a calendar component with an external attachment might therefore also delete the attachment if that's appropriate; however, appropriateness can be very hard to determine. A new component might easily reference some pre-existing Web resource that is intended to have independent existence from the calendar component (the "attachment" could be a major proposal to be discussed in a meeting, for instance). Best practices will probably emerge and should probably be documented, but for now, clients should be wary of engaging in aggressive "cleanup" of external attachments. A client could involve the user in making decisions about removing unreferenced documents, or a client could be conservative in only deleting attachments it had created.
Also, clients are responsible for consistency of permissions when using external attachments. One reason for servers to support the storage of attachments within child collections of calendar collections is that ACL inheritance might make it easier to grant the same permissions to attachments that are granted on the calendar collection. Otherwise, it can be very difficult to keep permissions synchronized. With attachments stored on separate repositories, it can be impossible to keep permissions consistent -- the two repositories may not support the same permissions or have the same set of principals. Some systems have used tickets or other anonymous access control mechanisms to provide partially satisfactory solutions to these kinds of problems.
Note that all CalDAV calendar collections (including those the user might treat as public or group calendars) can contain alarm information on events and to-dos. Users can synchronize a calendar between multiple devices and decide to have alarms execute on a different device than the device that created the alarm. Not all alarm action types are completely interoperable (e.g., those that name a sound file to play).
Non-interoperable alarm information (e.g., should somebody define a color to be used in a display alarm) should be put in non-standard properties inside the VALARM component in order to keep the basic alarm usable on all devices.
Clients that allow changes to calendar object resources MUST synchronize the alarm data that already exists in the resources. Clients MAY execute alarms that are downloaded in this fashion, possibly based on user preference. If a client is only doing read operations on a calendar and there is no risk of losing alarm information, then the client MAY discard alarm information.
This specification makes no attempt to provide multi-user alarms on group calendars or to find out for whom an alarm is intended. Addressing those issues might require extensions to iCalendar; for example, to store alarms per-user, or to indicate for which user a VALARM was intended. In the meantime, clients might maximize interoperability by generally not uploading alarm information to public, group, or resource calendars.
<!ELEMENT calendar EMPTY>
<!ELEMENT mkcalendar (DAV:set)>
<!ELEMENT mkcalendar-response ANY>
<!ELEMENT supported-collation (#PCDATA)>
PCDATA value: collation identifier
<!ELEMENT calendar-query ((DAV:allprop |
DAV:propname |
DAV:prop)?, filter, timezone?)>
<!ELEMENT calendar-data EMPTY>
when nested in the CALDAV:supported-calendar-data property
to specify a supported media type for calendar object
resources;
<!ELEMENT calendar-data (comp?,
(expand | limit-recurrence-set)?,
limit-freebusy-set?)>
when nested in the DAV:prop XML element in a calendaring
REPORT request to specify which parts of calendar object
resources should be returned in the response;
<!ELEMENT calendar-data (#PCDATA)>
PCDATA value: iCalendar object
when nested in the DAV:prop XML element in a calendaring
REPORT response to specify the content of a returned
calendar object resource.
<!ATTLIST calendar-data content-type CDATA "text/calendar"
version CDATA "2.0">
content-type value: a MIME media type
version value: a version string
attributes can be used on all three variants of the
CALDAV:calendar-data XML element.
<!ELEMENT comp ((allprop | prop*), (allcomp | comp*))>
<!ATTLIST comp name CDATA #REQUIRED>
name value: a calendar component name
<!ELEMENT allcomp EMPTY>
<!ELEMENT allprop EMPTY>
<!ELEMENT prop EMPTY>
<!ATTLIST prop name CDATA #REQUIRED
novalue (yes | no) "no">
name value: a calendar property name
novalue value: "yes" or "no"
<!ELEMENT expand EMPTY>
<!ATTLIST expand start CDATA #REQUIRED
end CDATA #REQUIRED>
start value: an iCalendar "date with UTC time"
end value: an iCalendar "date with UTC time"
<!ELEMENT limit-recurrence-set EMPTY>
<!ATTLIST limit-recurrence-set start CDATA #REQUIRED
end CDATA #REQUIRED>
start value: an iCalendar "date with UTC time"
end value: an iCalendar "date with UTC time"
<!ELEMENT limit-freebusy-set EMPTY>
<!ATTLIST limit-freebusy-set start CDATA #REQUIRED
end CDATA #REQUIRED>
start value: an iCalendar "date with UTC time"
end value: an iCalendar "date with UTC time"
<!ELEMENT filter (comp-filter)>
<!ELEMENT comp-filter (is-not-defined | (time-range?,
prop-filter*, comp-filter*))>
<!ATTLIST comp-filter name CDATA #REQUIRED>
name value: a calendar object or calendar component
type (e.g., VEVENT)
<!ELEMENT prop-filter (is-not-defined |
((time-range | text-match)?,
param-filter*))>
<!ATTLIST prop-filter name CDATA #REQUIRED>
name value: a calendar property name (e.g., ATTENDEE)
<!ELEMENT param-filter (is-not-defined | text-match?)>
<!ATTLIST param-filter name CDATA #REQUIRED>
name value: a property parameter name (e.g., PARTSTAT)
<!ELEMENT is-not-defined EMPTY>
<!ELEMENT text-match (#PCDATA)>
PCDATA value: string
<!ATTLIST text-match collation CDATA "i;ascii-casemap"
negate-condition (yes | no) "no">
<!ELEMENT timezone (#PCDATA)>
PCDATA value: an iCalendar object with exactly one VTIMEZONE
+---------------------------------------------------------------+
| VEVENT has the DTEND property? |
| +-----------------------------------------------------------+
| | VEVENT has the DURATION property? |
| | +-------------------------------------------------------+
| | | DURATION property value is greater than 0 seconds? |
| | | +---------------------------------------------------+
| | | | DTSTART property is a DATE-TIME value? |
| | | | +-----------------------------------------------+
| | | | | Condition to evaluate |
+---+---+---+---+-----------------------------------------------+
| Y | N | N | * | (start < DTEND AND end > DTSTART) |
+---+---+---+---+-----------------------------------------------+
| N | Y | Y | * | (start < DTSTART+DURATION AND end > DTSTART) |
| | +---+---+-----------------------------------------------+
| | | N | * | (start <= DTSTART AND end > DTSTART) |
+---+---+---+---+-----------------------------------------------+
| N | N | N | Y | (start <= DTSTART AND end > DTSTART) |
+---+---+---+---+-----------------------------------------------+
| N | N | N | N | (start < DTSTART+P1D AND end > DTSTART) |
+---+---+---+---+-----------------------------------------------+
+-------------------------------------------------------------------+
| VTODO has the DTSTART property? |
| +---------------------------------------------------------------+
| | VTODO has the DURATION property? |
| | +-----------------------------------------------------------+
| | | VTODO has the DUE property? |
| | | +-------------------------------------------------------+
| | | | VTODO has the COMPLETED property? |
| | | | +---------------------------------------------------+
| | | | | VTODO has the CREATED property? |
| | | | | +-----------------------------------------------+
| | | | | | Condition to evaluate |
+---+---+---+---+---+-----------------------------------------------+
| Y | Y | N | * | * | (start <= DTSTART+DURATION) AND |
| | | | | | ((end > DTSTART) OR |
| | | | | | (end >= DTSTART+DURATION)) |
+---+---+---+---+---+-----------------------------------------------+
| Y | N | Y | * | * | ((start < DUE) OR (start <= DTSTART)) |
| | | | | | AND |
| | | | | | ((end > DTSTART) OR (end >= DUE)) |
+---+---+---+---+---+-----------------------------------------------+
| Y | N | N | * | * | (start <= DTSTART) AND (end > DTSTART) |
+---+---+---+---+---+-----------------------------------------------+
| N | N | Y | * | * | (start < DUE) AND (end >= DUE) |
+---+---+---+---+---+-----------------------------------------------+
| N | N | N | Y | Y | ((start <= CREATED) OR (start <= COMPLETED))|
| | | | | | AND |
| | | | | | ((end >= CREATED) OR (end >= COMPLETED))|
+---+---+---+---+---+-----------------------------------------------+
| N | N | N | Y | N | (start <= COMPLETED) AND (end >= COMPLETED) |
+---+---+---+---+---+-----------------------------------------------+
| N | N | N | N | Y | (end > CREATED) |
+---+---+---+---+---+-----------------------------------------------+
| N | N | N | N | N | TRUE |
+---+---+---+---+---+-----------------------------------------------+
+----------------------------------------------------+
| VJOURNAL has the DTSTART property? |
| +------------------------------------------------+
| | DTSTART property is a DATE-TIME value? |
| | +--------------------------------------------+
| | | Condition to evaluate |
+---+---+--------------------------------------------+
| Y | Y | (start <= DTSTART) AND (end > DTSTART) |
+---+---+--------------------------------------------+
| Y | N | (start < DTSTART+P1D) AND (end > DTSTART) |
+---+---+--------------------------------------------+
| N | * | FALSE |
+---+---+--------------------------------------------+
+------------------------------------------------------+
| VFREEBUSY has both the DTSTART and DTEND properties? |
| +--------------------------------------------------+
| | VFREEBUSY has the FREEBUSY property? |
| | +----------------------------------------------+
| | | Condition to evaluate |
+---+---+----------------------------------------------+
| Y | * | (start <= DTEND) AND (end > DTSTART) |
+---+---+----------------------------------------------+
| N | Y | (start < freebusy-period-end) AND |
| | | (end > freebusy-period-start) |
+---+---+----------------------------------------------+
| N | N | FALSE |
+---+---+----------------------------------------------+
(start <= trigger-time) AND (end > trigger-time)A VALARM component can be defined such that it triggers repeatedly. Such a VALARM component is said to overlap a given time range if at least one of its triggers overlaps the time range.
(start <= date-time) AND (end > date-time)Note that if DTEND is not present in a VEVENT, but DURATION is, then the test should instead operate on the 'effective' DTEND, i.e., DTSTART+DURATION. Similarly, if DUE is not present in a VTODO, but DTSTART and DURATION are, then the test should instead operate on the 'effective' DUE, i.e., DTSTART+DURATION.
<!ELEMENT time-range EMPTY>
<!ATTLIST time-range start CDATA #IMPLIED
end CDATA #IMPLIED>
start value: an iCalendar "date with UTC time"
end value: an iCalendar "date with UTC time"
<!ELEMENT calendar-multiget ((DAV:allprop |
DAV:propname |
DAV:prop)?, DAV:href+)>
<!ELEMENT free-busy-query (time-range)>
CalDAV allows internationalized strings to be stored and retrieved for the description of calendar collections (see Section�5.2.1).
The CALDAV:calendar-query REPORT (Section�7.8) includes a text searching option controlled by the CALDAV:text-match element, and details of character handling are covered in the description of that element (see Section�9.7.5).
HTTP protocol transactions are sent in the clear over the network unless protection from snooping is negotiated. This can be accomplished by use of TLS, as defined in [RFC2818]. In particular, HTTP Basic authentication MUST NOT be used unless TLS is in effect.
Servers MUST take adequate precautions to ensure that malicious clients cannot consume excessive server resources (CPU, memory, disk, etc.) through carefully crafted reports. For example, a client could upload an event with a recurrence rule that specifies a recurring event occurring every second for the next 100 years, which would result in approximately 3 x 10^9 instances! A report that asks for recurrences to be expanded over that range would likely constitute a denial-of-service attack on the server.
When creating new resources (including calendar collections), clients MUST ensure that the resource name (the last path segment of the resource URI) assigned to the new resource does not expose any data from within the iCalendar resource itself or information about the nature of a calendar collection. This is required to ensure that the presence of a specific iCalendar component or nature of components in a collection cannot be inferred based on the name of a resource.
When rolling up free-busy information, more information about a user's events is exposed if busy periods overlap or are adjacent (this tells the client requesting the free-busy information that the calendar owner has at least two events, rather than knowing only that the calendar owner has one or more events during the busy period). Thus, a conservative approach to calendar data privacy would have servers always coalesce such busy periods when they are the same type.
Procedure alarms are a known security risk for either clients or servers to handle, particularly when the alarm was created by another agent. Clients and servers are not required to execute such procedure alarms.
Security considerations described in iCalendar [RFC2445] and iTIP [RFC2446] are also applicable to CalDAV.
Beyond these, CalDAV does not raise any security considerations that are not present in HTTP [RFC2616] and WebDAV [RFC2518], [RFC3253], [RFC3744].
This document uses one new URN to identify a new XML namespace. The URN conforms to a registry mechanism described in [RFC3688].
Registration request for the CalDAV namespace:
URI: urn:ietf:params:xml:ns:caldav
Registrant Contact: See the "Authors' Addresses" section of this document.
XML: None. Namespace URIs do not represent an XML specification.
The authors would like to thank the following individuals for contributing their ideas and support for writing this specification: Michael Arick, Mario Bonin, Chris Bryant, Scott Carr, Andre Courtemanche, Mike Douglass, Ted Hardie, Marten den Haring, Jeffrey Harris, Sam Hartman, Helge Hess, Jeff McCullough, Alexey Melnikov, Dan Mosedale, Brian Moseley, Francois Perrault, Kervin L. Pierre, Julian F. Reschke, Wilfredo Sanchez Vega, Mike Shaver, Jari Urpalainen, Simon Vaillancourt, and Jim Whitehead.
The authors would also like to thank the Calendaring and Scheduling Consortium for advice with this specification, and for organizing interoperability testing events to help refine it.
| [RFC2426] | Dawson, F. and T. Howes, “vCard MIME Directory Profile”, RFC�2426, September�1998. |
| [rfc2518bis] | Dusseault, L., “HTTP Extensions for Distributed Authoring - WebDAV”, Work in�Progress, December�2006. |
| [RFC2739] | Small, T., Hennessy, D., and F. Dawson, “Calendar Attributes for vCard and LDAP”, RFC�2739, January�2000. |
| [RFC4331] | Korver, B. and L. Dusseault, “Quota and Size Properties for Distributed Authoring and Versioning (DAV) Collections”, RFC�4331, February�2006. |
| [RFC4511] | Sermersheim, J., “Lightweight Directory Access Protocol (LDAP): The Protocol”, RFC�4511, June�2006. |
The following table extends the WebDAV Method Privilege Table specified in Appendix B of [RFC3744].
| METHOD | PRIVILEGES |
|---|---|
| MKCALENDAR | DAV:bind |
| REPORT | DAV:read or CALDAV:read-free-busy (on all referenced resources) |
This appendix shows the calendar object resources contained in the calendar collection queried in the examples throughout this document.
The content of the calendar collection is being shown as if it were returned by a CALDAV:calendar-query REPORT request designed to return all the calendar data in the collection:
>> Request <<
REPORT /bernard/work/ HTTP/1.1
Host: cal.example.com
Depth: 1
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<C:calendar-query xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:prop>
<D:getetag/>
<C:calendar-data/>
</D:prop>
<C:filter>
<C:comp-filter name="VCALENDAR"/>
</C:filter>
</C:calendar-query>
>> Response <<
HTTP/1.1 207 Multi-Status
Content-Type: application/xml; charset="utf-8"
Content-Length: xxxx
<?xml version="1.0" encoding="utf-8" ?>
<D:multistatus xmlns:D="DAV:"
xmlns:C="urn:ietf:params:xml:ns:caldav">
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd1.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd1"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20060206T001102Z
DTSTART;TZID=US/Eastern:20060102T100000
DURATION:PT1H
SUMMARY:Event #1
Description:Go Steelers!
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd2.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd2"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART;TZID=US/Eastern:20060102T120000
DURATION:PT1H
RRULE:FREQ=DAILY;COUNT=5
SUMMARY:Event #2
UID:[email protected]
END:VEVENT
BEGIN:VEVENT
DTSTAMP:20060206T001121Z
DTSTART;TZID=US/Eastern:20060104T140000
DURATION:PT1H
RECURRENCE-ID;TZID=US/Eastern:20060104T120000
SUMMARY:Event #2 bis
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd3.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd3"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTIMEZONE
LAST-MODIFIED:20040110T032845Z
TZID:US/Eastern
BEGIN:DAYLIGHT
DTSTART:20000404T020000
RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
TZNAME:EDT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20001026T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:EST
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
ATTENDEE;PARTSTAT=ACCEPTED;ROLE=CHAIR:mailto:[email protected]
ATTENDEE;PARTSTAT=NEEDS-ACTION:mailto:[email protected]
DTSTAMP:20060206T001220Z
DTSTART;TZID=US/Eastern:20060104T100000
DURATION:PT1H
LAST-MODIFIED:20060206T001330Z
ORGANIZER:mailto:[email protected]
SEQUENCE:1
STATUS:TENTATIVE
SUMMARY:Event #3
UID:[email protected]
END:VEVENT
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd4.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd4"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTODO
DTSTAMP:20060205T235335Z
DUE;VALUE=DATE:20060104
STATUS:NEEDS-ACTION
SUMMARY:Task #1
UID:[email protected]
BEGIN:VALARM
ACTION:AUDIO
TRIGGER;RELATED=START:-PT10M
END:VALARM
END:VTODO
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd5.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd5"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTODO
DTSTAMP:20060205T235300Z
DUE;VALUE=DATE:20060106
LAST-MODIFIED:20060205T235308Z
SEQUENCE:1
STATUS:NEEDS-ACTION
SUMMARY:Task #2
UID:[email protected]
BEGIN:VALARM
ACTION:AUDIO
TRIGGER;RELATED=START:-PT10M
END:VALARM
END:VTODO
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd6.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd6"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTODO
COMPLETED:20051223T122322Z
DTSTAMP:20060205T235400Z
DUE;VALUE=DATE:20051225
LAST-MODIFIED:20060205T235308Z
SEQUENCE:1
STATUS:COMPLETED
SUMMARY:Task #3
UID:[email protected]
END:VTODO
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd7.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd7"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VTODO
DTSTAMP:20060205T235600Z
DUE;VALUE=DATE:20060101
LAST-MODIFIED:20060205T235308Z
SEQUENCE:1
STATUS:CANCELLED
SUMMARY:Task #4
UID:[email protected]
END:VTODO
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
<D:response>
<D:href>http://cal.example.com/bernard/work/abcd8.ics</D:href>
<D:propstat>
<D:prop>
<D:getetag>"fffff-abcd8"</D:getetag>
<C:calendar-data>BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Example Corp.//CalDAV Client//EN
BEGIN:VFREEBUSY
ORGANIZER;CN="Bernard Desruisseaux":mailto:[email protected]
UID:[email protected]
DTSTAMP:20050530T123421Z
DTSTART:20060101T000000Z
DTEND:20060108T000000Z
FREEBUSY:20050531T230000Z/20050601T010000Z
FREEBUSY;FBTYPE=BUSY-TENTATIVE:20060102T100000Z/20060102T120000Z
FREEBUSY:20060103T100000Z/20060103T120000Z
FREEBUSY:20060104T100000Z/20060104T120000Z
FREEBUSY;FBTYPE=BUSY-UNAVAILABLE:20060105T100000Z/20060105T120000Z
FREEBUSY:20060106T100000Z/20060106T120000Z
END:VFREEBUSY
END:VCALENDAR
</C:calendar-data>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus> Copyright � The IETF Trust (2007).
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