MIT License

(short answer) "An application server that efficiently integrates with many languages, many databases, and many messaging buses in a way that is both scalable and fault-tolerant."

(shorter answer) "A rock-solid transaction processing system for flexible software development."

(shortest answer) "A Cloud at the lowest level."

Software developers that do not want to get locked into corporate vendors or frameworks that push for perpetual commercial support or licenses.

CloudI makes software fault-tolerant and scalable, utilizing Erlang, even if the software is legacy source code. CloudI mitigates software development risk (delays or failures) when making software scale in non-Erlang programming languages, or during a conversion of a software system (fully or partially) to the Erlang programming language.

The CloudI API provides a simple set of functions for Service-Oriented Architecture (SOA) development in any supported language (currently C/C++, Go, Haskell, Java, JavaScript, OCaml, Perl, PHP, Python, Ruby, and Erlang/Elixir):

• subscribe, unsubscribe, subscribe_count
• send_async, send_sync, mcast_async (mcast_async == publish)
• recv_async
• return, forward

External communication that needs to scale (beyond 10,000 connections) can use an existing internal CloudI service (implemented in Erlang or Elixir) which may do processing for one or more external CloudI services (implemented in C/C++, Go, Haskell, Java, JavaScript, OCaml, Perl, PHP, Python, and/or Ruby)

Even if external communication doesn't need to scale, private cloud computing tasks (number crunching) can gain fault-tolerance and internal system scalability within CloudI.

Please see the FAQ for more details.

• Erlang >= 19.0 (erlang/Ubuntu, erlang/macports)
• C++ (g++/Ubuntu, libstdcxx/macports)
• boost >= 1.36.0 (libboost-system-dev+libboost-thread-dev+libboost-dev/Ubuntu, boost/macports)

Optional (default="yes"):

• Java >= 1.5 JDK
  • (default-jdk/Ubuntu, (built-in)/OSX)
  • Use the "--enable-java-support=no" configure flag to disable
• Javascript >= 0.8.0
  • (nodejs/Ubuntu)
  • Use the "--enable-javascript-support=no" configure flag to disable
• Perl >= 5.10
  • (perl/Ubuntu)
  • Compress::Zlib (cpan)
  • Use the "--enable-perl-support=no" configure flag to disable
• PHP >= 5.3.6
  • (php5/Ubuntu)
  • Use the "--enable-php-support=no" configure flag to disable
• Python >= 2.7.0
  • (python+python-dev/Ubuntu, python27/macports)
  • Use the "--enable-python-support=no" and "--enable-python-c-support=no" configure flag to disable
• Ruby >= 1.9.0
  • (ruby1.9.1/Ubuntu, ruby19/macports)
  • Use the "--enable-ruby-support=no" configure flag to disable
• GNU MP library
  • (libgmp3-dev/Ubuntu, gmp/macports)
  • Used in the hexpi (C++) integration test only ("--with-integration-tests=no" configure flag to disable)

Optional (default="no"):

• Go >= 1.6
  • (golang/Ubuntu, go/macports)
  • Use the "--enable-go-support" configure flag to enable
• Haskell (GHC >= 7.10.3 and cabal-install >= 1.22)
  • Use the "--enable-haskell-support" configure flag to enable
• OCaml >= 4.03.0
  • Use the "--enable-ocaml-support" configure flag to enable
• ZeroMQ >= 3.x.x or 2.x.x
  • uuid-dev (uuid-dev/Ubuntu, ossp-uuid/macports)
  • Use the "--with-zeromq" configure flag to enable

For configuration options, see FAQ: 3.2 - Installation Options.

./configure
make
sudo make install

Within the installation directory the cloudi script controls CloudI.

To start CloudI:

sudo cloudi start

To stop CloudI:

sudo cloudi stop

See the Quick Start Guide or the API documentation

Integration points:

• CloudI API (See src/api/README.markdown)
• HTTP with cloudi_service_http_cowboy and cloudi_service_http_elli
• ZeroMQ with cloudi_service_zeromq
• OAuth v1 with cloudi_service_oauth1
• TCP with cloudi_service_tcp
• UDP with cloudi_service_udp
• Supported databases (included)
  • MySQL with cloudi_service_db_mysql
  • PostgreSQL with cloudi_service_db_pgsql
• Supported databases (excluded)
  • elasticsearch with cloudi_service_db_elasticsearch
  • Cassandra with cloudi_service_db_cassandra or cloudi_service_db_cassandra_cql
  • CouchDB with cloudi_service_db_couchdb
  • memcached with cloudi_service_db_memcached
  • Riak with cloudi_service_db_riak
  • TokyoTyrant with cloudi_service_db_tokyotyrant

Dynamic Configuration and Monitoring:

• CloudI Service API (See src/service_api/README.markdown)
• Monitoring to Graphite, OpenTSDB, SNMP, InfluxDB or StatsD with cloudi_service_monitoring

Routing:

• Caching Static File Data with cloudi_service_filesystem
• HTTP Client Requests with cloudi_service_http_client
• HTTP REST Handlers with cloudi_service_http_rest
• Fault-Tolerant Map-Reduce with cloudi_service_map_reduce (See the hexpi integration test controller)
• Durable Service Requests with cloudi_service_queue
• Service Redundancy with cloudi_service_quorum
• Altering Request Destinations with cloudi_service_router
• Validation with cloudi_service_validate

The default CloudI configuration can run the included integration tests if all the supported programming languages are enabled at configure time (they are by default) and the --with-integration-tests-ran configuration argument is used (to choose the src/cloudi_tests.conf.in file).

If the --with-integration-tests-ran configuration argument is not used, the more minimal CloudI configuration will be used instead (in the src/cloudi_minimal.conf.in file) to support basic things like the Quick Start Guide, the Dashboard and any tutorials or examples.

Michael Truog (mjtruog [at] gmail (dot) com)