Merge pull request #425 from SimonRichardson/remove-metrics-code

#425

We no longer support metrics code, so we should remove the code. Moving it to dqlite would require understanding and maintaining code that has not full tested or integrated with romulus or omnibus is sometime. Fully understanding if all parts are correct would be challenging.

If in the future we want to reuse parts, we can always look back in the history of the repo to bring back the parts that are required (if any).

README.md

@@ -55,11 +55,6 @@ All the other fields are optional.
 The type can be either a `string`, `int`, `float` or `boolean`. Everything else
 will cause Juju to error out when reading the charm.
 
-### `metrics.yaml`
-
-`metrics.yaml` represents an optional metrics gathering configuration yaml. For
-more information about metrics, read up on [Metric collecting charms](https://discourse.juju.is/t/metric-collecting-charms/1125)
-
 ### `revision`
 
 The `revision` is used to indicate the revision of a charm. It expects that only

charm.go

@@ -26,7 +26,6 @@ type CharmMeta interface {
 type Charm interface {
 	CharmMeta
 	Config() *Config
-	Metrics() *Metrics
 	Actions() *Actions
 	Revision() int
 }

charmarchive.go

@@ -105,17 +105,6 @@ func readCharmArchive(zopen zipOpener) (archive *CharmArchive, err error) {
 		}
 	}
 
-	reader, err = zipOpenFile(zipr, "metrics.yaml")
-	if err == nil {
-		b.metrics, err = ReadMetrics(reader)
-		_ = reader.Close()
-		if err != nil {
-			return nil, err
-		}
-	} else if _, ok := err.(*noCharmArchiveFile); !ok {
-		return nil, err
-	}
-
 	if b.actions, err = getActions(
 		b.meta.Name,
 		func(file string) (io.ReadCloser, error) {

charmarchive_test.go

@@ -104,32 +104,6 @@ func (s *CharmArchiveSuite) TestReadCharmArchiveWithoutManifest(c *gc.C) {
 	c.Assert(dir.Manifest(), gc.IsNil)
 }
 
-func (s *CharmArchiveSuite) TestReadCharmArchiveWithoutMetrics(c *gc.C) {
-	path := archivePath(c, readCharmDir(c, "varnish"))
-	dir, err := charm.ReadCharmArchive(path)
-	c.Assert(err, gc.IsNil)
-
-	// A lacking metrics.yaml file indicates the unit will not
-	// be metered.
-	c.Assert(dir.Metrics(), gc.IsNil)
-}
-
-func (s *CharmArchiveSuite) TestReadCharmArchiveWithEmptyMetrics(c *gc.C) {
-	path := archivePath(c, readCharmDir(c, "metered-empty"))
-	dir, err := charm.ReadCharmArchive(path)
-	c.Assert(err, gc.IsNil)
-	c.Assert(Keys(dir.Metrics()), gc.HasLen, 0)
-}
-
-func (s *CharmArchiveSuite) TestReadCharmArchiveWithCustomMetrics(c *gc.C) {
-	path := archivePath(c, readCharmDir(c, "metered"))
-	dir, err := charm.ReadCharmArchive(path)
-	c.Assert(err, gc.IsNil)
-
-	c.Assert(dir.Metrics(), gc.NotNil)
-	c.Assert(Keys(dir.Metrics()), gc.DeepEquals, []string{"juju-unit-time", "pings"})
-}
-
 func (s *CharmArchiveSuite) TestReadCharmArchiveWithoutActions(c *gc.C) {
 	// Wordpress has config but no actions.
 	path := archivePath(c, readCharmDir(c, "wordpress"))

charmbase.go

@@ -8,7 +8,6 @@ package charm
 type charmBase struct {
 	meta       *Meta
 	config     *Config
-	metrics    *Metrics
 	actions    *Actions
 	lxdProfile *LXDProfile
 	manifest   *Manifest
@@ -39,12 +38,6 @@ func (c *charmBase) Config() *Config {
 	return c.config
 }
 
-// Metrics returns the Metrics representing the metrics.yaml file
-// for the charm expanded in dir.
-func (c *charmBase) Metrics() *Metrics {
-	return c.metrics
-}
-
 // Actions returns the Actions representing the actions.yaml file
 // for the charm expanded in dir.
 func (c *charmBase) Actions() *Actions {

charmdir.go

@@ -103,17 +103,6 @@ func ReadCharmDir(path string) (*CharmDir, error) {
 		}
 	}
 
-	reader, err = os.Open(b.join("metrics.yaml"))
-	if err == nil {
-		b.metrics, err = ReadMetrics(reader)
-		_ = reader.Close()
-		if err != nil {
-			return nil, errors.Annotatef(err, `parsing "metrics.yaml" file`)
-		}
-	} else if !os.IsNotExist(err) {
-		return nil, errors.Annotatef(err, `reading "metrics.yaml" file`)
-	}
-
 	if b.actions, err = getActions(
 		b.meta.Name,
 		func(file string) (io.ReadCloser, error) {

charmdir_test.go

@@ -63,32 +63,6 @@ func (s *CharmDirSuite) TestReadCharmDirWithoutConfig(c *gc.C) {
 	c.Assert(dir.Config().Options, gc.HasLen, 0)
 }
 
-func (s *CharmDirSuite) TestReadCharmDirWithoutMetrics(c *gc.C) {
-	path := charmDirPath(c, "varnish")
-	dir, err := charm.ReadCharmDir(path)
-	c.Assert(err, gc.IsNil)
-
-	// A lacking metrics.yaml file indicates the unit will not
-	// be metered.
-	c.Assert(dir.Metrics(), gc.IsNil)
-}
-
-func (s *CharmDirSuite) TestReadCharmDirWithEmptyMetrics(c *gc.C) {
-	path := charmDirPath(c, "metered-empty")
-	dir, err := charm.ReadCharmDir(path)
-	c.Assert(err, gc.IsNil)
-	c.Assert(Keys(dir.Metrics()), gc.HasLen, 0)
-}
-
-func (s *CharmDirSuite) TestReadCharmDirWithCustomMetrics(c *gc.C) {
-	path := charmDirPath(c, "metered")
-	dir, err := charm.ReadCharmDir(path)
-	c.Assert(err, gc.IsNil)
-
-	c.Assert(dir.Metrics(), gc.NotNil)
-	c.Assert(Keys(dir.Metrics()), gc.DeepEquals, []string{"juju-unit-time", "pings"})
-}
-
 func (s *CharmDirSuite) TestReadCharmDirWithoutActions(c *gc.C) {
 	path := charmDirPath(c, "wordpress")
 	dir, err := charm.ReadCharmDir(path)
@@ -461,7 +435,7 @@ func (s *CharmDirSuite) assertArchiveTo(c *gc.C, baseDir, charmDir string) {
 
 // Bug #864164: Must complain if charm hooks aren't executable
 func (s *CharmDirSuite) TestArchiveToWithNonExecutableHooks(c *gc.C) {
-	hooks := []string{"install", "start", "config-changed", "upgrade-charm", "stop", "collect-metrics", "meter-status-changed"}
+	hooks := []string{"install", "start", "config-changed", "upgrade-charm", "stop"}
 	for _, relName := range []string{"foo", "bar", "self"} {
 		for _, kind := range []string{"joined", "changed", "departed", "broken"} {
 			hooks = append(hooks, relName+"-relation-"+kind)

export_test.go

@@ -7,7 +7,6 @@ package charm
 
 var (
 	IfaceExpander = ifaceExpander
-	ValidateValue = validateValue
 
 	ParsePayloadClass         = parsePayloadClass
 	ResourceSchema            = resourceSchema

hooks/hooks.go

@@ -19,8 +19,6 @@ const (
 	Stop                  Kind = "stop"
 	Remove                Kind = "remove"
 	Action                Kind = "action"
-	CollectMetrics        Kind = "collect-metrics"
-	MeterStatusChanged    Kind = "meter-status-changed"
 	LeaderElected         Kind = "leader-elected"
 	LeaderDeposed         Kind = "leader-deposed"
 	LeaderSettingsChanged Kind = "leader-settings-changed"
@@ -72,8 +70,6 @@ var unitHooks = []Kind{
 	UpgradeCharm,
 	Stop,
 	Remove,
-	CollectMetrics,
-	MeterStatusChanged,
 	LeaderElected,
 	LeaderDeposed,
 	LeaderSettingsChanged,

meta_test.go

@@ -730,8 +730,6 @@ func (s *MetaSuite) TestMetaHooks(c *gc.C) {
 		"upgrade-charm":                     true,
 		"stop":                              true,
 		"remove":                            true,
-		"collect-metrics":                   true,
-		"meter-status-changed":              true,
 		"leader-elected":                    true,
 		"leader-deposed":                    true,
 		"leader-settings-changed":           true,
@@ -1922,10 +1920,6 @@ func (c *dummyCharm) Config() *charm.Config {
 	panic("unused")
 }
 
-func (c *dummyCharm) Metrics() *charm.Metrics {
-	panic("unused")
-}
-
 func (c *dummyCharm) Actions() *charm.Actions {
 	panic("unused")
 }