storage: create common constraint values struct

bnhassin · Jan 5, 2015 · d444d0a · d444d0a
1 parent 5a183bc
commit d444d0a
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Showing 3 changed files with 74 additions and 76 deletions.
diff --git a/dependencies.tsv b/dependencies.tsv
@@ -21,7 +21,7 @@ github.com/juju/schema	git	27a52be50766490a6fd3531865095fda6c0eeb6d
 github.com/juju/syslog	git	2b69d6582feb16ff8b6d644495e16c2d8314fcb8	
 github.com/juju/testing	git	839334678c08487fb1c6ab032893fc8c85d74756	
 github.com/juju/txn	git	e02f26c56cfb81c7c1236df499deebb0369bd97c	
-github.com/juju/utils	git	c1f38bc81aa18a8fff86ffbd8d5587b218118d3d	
+github.com/juju/utils	git	37016f78b9989f99222a5e09a26e25db124c1b17	2014-12-05T10:56:08+08:00
 gopkg.in/check.v1	git	91ae5f88a67b14891cfd43895b01164f6c120420	
 gopkg.in/juju/charm.v4	git	f7e5613ff75457d2700d1c3269546cc903ea0471	
 gopkg.in/mgo.v2	git	dc255bb679efa273b6544a03261c4053505498a4	

diff --git a/storage/constraints.go b/storage/constraints.go
@@ -17,39 +17,34 @@ var logger = loggo.GetLogger("juju.storage")
 
 // Constraints describes a set of storage constraints.
 type Constraints struct {
-	// Size is the preferred size of the storage in MiB.
-	Size uint64
+	// Source is the name of the storage source (ebs, ceph, ...) that
+	// must provide the storage, or "" if any source may be used.
+	Source string
 
-	// MinimumSize is the minimum size of the storage in MiB.
-	MinimumSize uint64
+	// Minimum is the minimum acceptable values for each constraint variable.
+	Minimum ConstraintValues
 
-	// Count is the preferred number of instances of the
-	// storage to create.
-	Count uint64
+	// Preferred is the preferred values for each constraint variable.
+	Preferred ConstraintValues
+}
 
-	// MinimumCount is the minimum number of instances of the
-	// storage to create.
-	MinimumCount uint64
+// ConstraintValues describes the constraints on individual storage
+// characteristics.
+type ConstraintValues struct {
+	// Size is the size of the storage in MiB.
+	Size uint64
+
+	// Count is the number of instances of the storage to create.
+	Count uint64
 
 	// Persistent indicates that the storage should be persistent
 	// beyond the lifetime of the machine that it is initially
 	// attached to.
 	Persistent bool
 
-	// RequirePersistent indicates that the storage must be persistent.
-	RequirePersistent bool
-
-	// IOPS is the preferred number of IOPS (I/O Operations Per Second)
-	// that the storage should be capable of.
+	// IOPS is the number of IOPS (I/O Operations Per Second) that the
+	// storage should be capable of.
 	IOPS uint64
-
-	// MinimumIOPS is the minimum number of IOPS that the storage must
-	// be capable of.
-	MinimumIOPS uint64
-
-	// Source is the name of the storage source (ebs, ceph, ...) that
-	// must provide the storage, or "" if any source may be used.
-	Source string
 }
 
 const (
@@ -105,18 +100,18 @@ func ParseConstraints(s string) (Constraints, error) {
 	if countSizeMatch != nil {
 		if countSizeMatch[1] != "" {
 			if countSizeMatch[1][0] != '-' {
-				cons.Count, err = strconv.ParseUint(countSizeMatch[1], 10, 64)
+				cons.Preferred.Count, err = strconv.ParseUint(countSizeMatch[1], 10, 64)
 				if err != nil {
 					return cons, errors.Annotatef(err, "cannot parse count %q", countSizeMatch[1])
 				}
 			}
-			if cons.Count == 0 {
+			if cons.Preferred.Count == 0 {
 				return cons, errors.Errorf("count must be greater than zero, got %q", countSizeMatch[1])
 			}
 		} else {
-			cons.Count = 1
+			cons.Preferred.Count = 1
 		}
-		cons.Size, err = utils.ParseSize(countSizeMatch[2])
+		cons.Preferred.Size, err = utils.ParseSize(countSizeMatch[2])
 		if err != nil {
 			return cons, errors.Annotate(err, "cannot parse size")
 		}
@@ -128,10 +123,10 @@ func ParseConstraints(s string) (Constraints, error) {
 		switch {
 		case field == "":
 		case field == "persistent":
-			cons.Persistent = true
+			cons.Preferred.Persistent = true
 		case strings.HasPrefix(strings.ToLower(field), "iops:"):
 			value := field[len("iops:"):]
-			cons.IOPS, err = strconv.ParseUint(value, 10, 64)
+			cons.Preferred.IOPS, err = strconv.ParseUint(value, 10, 64)
 			if err != nil {
 				return cons, errors.Annotatef(err, "cannot parse IOPS %q", value)
 			}
@@ -140,9 +135,8 @@ func ParseConstraints(s string) (Constraints, error) {
 		}
 	}
 
-	cons.MinimumCount = cons.Count
-	cons.MinimumSize = cons.Size
-	cons.RequirePersistent = cons.Persistent
-	cons.MinimumIOPS = cons.IOPS
+	// Explicitly specified constraints are always required;
+	// the minimum is the same as the preferred.
+	cons.Minimum = cons.Preferred
 	return cons, nil
 }
diff --git a/storage/constraints_test.go b/storage/constraints_test.go
@@ -16,77 +16,78 @@ var _ = gc.Suite(&ConstraintsSuite{})
 
 func (s *ConstraintsSuite) TestParseConstraintsStorageSource(c *gc.C) {
 	s.testParse(c, "provider:1M", storage.Constraints{
-		Source:       "provider",
-		Count:        1,
-		MinimumCount: 1,
-		Size:         1,
-		MinimumSize:  1,
+		Source: "provider",
+		Preferred: storage.ConstraintValues{
+			Count: 1,
+			Size:  1,
+		},
 	})
 	s.testParse(c, "provider0123:", storage.Constraints{
 		Source: "provider0123",
 	})
 	s.testParse(c, ":", storage.Constraints{})
 	s.testParse(c, "1M", storage.Constraints{
-		Count:        1,
-		MinimumCount: 1,
-		Size:         1,
-		MinimumSize:  1,
+		Preferred: storage.ConstraintValues{
+			Size:  1,
+			Count: 1,
+		},
 	})
 }
 
 func (s *ConstraintsSuite) TestParseConstraintsCountSize(c *gc.C) {
 	s.testParse(c, "s:1G", storage.Constraints{
-		Source:       "s",
-		Count:        1,
-		MinimumCount: 1,
-		Size:         1024,
-		MinimumSize:  1024,
+		Source: "s",
+		Preferred: storage.ConstraintValues{
+			Count: 1,
+			Size:  1024,
+		},
 	})
 	s.testParse(c, "s:1x0.5T", storage.Constraints{
-		Source:       "s",
-		Count:        1,
-		MinimumCount: 1,
-		Size:         1024 * 512,
-		MinimumSize:  1024 * 512,
+		Source: "s",
+		Preferred: storage.ConstraintValues{
+			Count: 1,
+			Size:  1024 * 512,
+		},
 	})
 	s.testParse(c, "s:3x0.125P", storage.Constraints{
-		Source:       "s",
-		Count:        3,
-		MinimumCount: 3,
-		Size:         1024 * 1024 * 128,
-		MinimumSize:  1024 * 1024 * 128,
+		Source: "s",
+		Preferred: storage.ConstraintValues{
+			Count: 3,
+			Size:  1024 * 1024 * 128,
+		},
 	})
 }
 
 func (s *ConstraintsSuite) TestParseConstraintsOptions(c *gc.C) {
 	s.testParse(c, "s:1M,", storage.Constraints{
-		Source:       "s",
-		Count:        1,
-		MinimumCount: 1,
-		Size:         1,
-		MinimumSize:  1,
+		Source: "s",
+		Preferred: storage.ConstraintValues{
+			Count: 1,
+			Size:  1,
+		},
 	})
 	s.testParse(c, "s:anyoldjunk", storage.Constraints{
 		Source: "s",
 	})
 	s.testParse(c, "s:persistent", storage.Constraints{
-		Source:            "s",
-		Persistent:        true,
-		RequirePersistent: true,
+		Source: "s",
+		Preferred: storage.ConstraintValues{
+			Persistent: true,
+		},
 	})
 	s.testParse(c, "s:persistent,iops:10000", storage.Constraints{
-		Source:            "s",
-		Persistent:        true,
-		RequirePersistent: true,
-		IOPS:              10000,
-		MinimumIOPS:       10000,
+		Source: "s",
+		Preferred: storage.ConstraintValues{
+			Persistent: true,
+			IOPS:       10000,
+		},
 	})
 	s.testParse(c, "s:iops:10000,persistent", storage.Constraints{
-		Source:            "s",
-		Persistent:        true,
-		RequirePersistent: true,
-		IOPS:              10000,
-		MinimumIOPS:       10000,
+		Source: "s",
+		Preferred: storage.ConstraintValues{
+			Persistent: true,
+			IOPS:       10000,
+		},
 	})
 }
 
@@ -101,6 +102,9 @@ func (s *ConstraintsSuite) TestParseConstraintsSizeRange(c *gc.C) {
 }
 
 func (*ConstraintsSuite) testParse(c *gc.C, s string, expect storage.Constraints) {
+	// ParseConstraints should always return min=preferred. Avoid repetitious
+	// tests by setting the expectation here.
+	expect.Minimum = expect.Preferred
 	cons, err := storage.ParseConstraints(s)
 	c.Check(err, jc.ErrorIsNil)
 	c.Check(cons, gc.DeepEquals, expect)