Merge pull request #19 from libp2p/feat/metrics-redux

Add OpenCensus metrics registration functionality to core

go.mod

@@ -12,5 +12,6 @@ require (
 	github.com/multiformats/go-multiaddr v0.0.4
 	github.com/multiformats/go-multihash v0.0.5
 	github.com/spacemonkeygo/openssl v0.0.0-20181017203307-c2dcc5cca94a
+	go.opencensus.io v0.21.0
 	golang.org/x/crypto v0.0.0-20190618222545-ea8f1a30c443
 )

go.sum

-github.com/aead/siphash v1.0.1 h1:FwHfE/T45KPKYuuSAKyyvE+oPWcaQ+CUmFW0bPlM+kg=
+cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/aead/siphash v1.0.1/go.mod h1:Nywa3cDsYNNK3gaciGTWPwHt0wlpNV15vwmswBAUSII=
 github.com/btcsuite/btcd v0.0.0-20190523000118-16327141da8c h1:aEbSeNALREWXk0G7UdNhR3ayBV7tZ4M2PNmnrCAph6Q=
 github.com/btcsuite/btcd v0.0.0-20190523000118-16327141da8c/go.mod h1:3J08xEfcugPacsc34/LKRU2yO7YmuT8yt28J8k2+rrI=
@@ -15,6 +16,7 @@ github.com/btcsuite/snappy-go v0.0.0-20151229074030-0bdef8d06723/go.mod h1:8woku
 github.com/btcsuite/websocket v0.0.0-20150119174127-31079b680792 h1:R8vQdOQdZ9Y3SkEwmHoWBmX1DNXhXZqlTpq6s4tyJGc=
 github.com/btcsuite/websocket v0.0.0-20150119174127-31079b680792/go.mod h1:ghJtEyQwv5/p4Mg4C0fgbePVuGr935/5ddU9Z3TmDRY=
 github.com/btcsuite/winsvc v1.0.0/go.mod h1:jsenWakMcC0zFBFurPLEAyrnc/teJEM1O46fmI40EZs=
+github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/davecgh/go-spew v0.0.0-20171005155431-ecdeabc65495 h1:6IyqGr3fnd0tM3YxipK27TUskaOVUjU2nG45yzwcQKY=
@@ -22,11 +24,17 @@ github.com/davecgh/go-spew v0.0.0-20171005155431-ecdeabc65495/go.mod h1:J7Y8YcW2
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/gogo/protobuf v1.2.1 h1:/s5zKNz0uPFCZ5hddgPdo2TK2TVrUNMn0OOX8/aZMTE=
 github.com/gogo/protobuf v1.2.1/go.mod h1:hp+jE20tsWTFYpLwKvXlhS1hjn+gTNwPg2I6zVXpSg4=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
+github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/google/go-cmp v0.2.0 h1:+dTQ8DZQJz0Mb/HjFlkptS1FeQ4cWSnN941F8aEG4SQ=
+github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/gxed/hashland/keccakpg v0.0.1 h1:wrk3uMNaMxbXiHibbPO4S0ymqJMm41WiudyFSs7UnsU=
 github.com/gxed/hashland/keccakpg v0.0.1/go.mod h1:kRzw3HkwxFU1mpmPP8v1WyQzwdGfmKFJ6tItnhQ67kU=
 github.com/gxed/hashland/murmur3 v0.0.1 h1:SheiaIt0sda5K+8FLz952/1iWS9zrnKsEJaOJu4ZbSc=
 github.com/gxed/hashland/murmur3 v0.0.1/go.mod h1:KjXop02n4/ckmZSnY2+HKcLud/tcmvhST0bie/0lS48=
+github.com/hashicorp/golang-lru v0.5.0 h1:CL2msUPvZTLb5O648aiLNJw3hnBxN2+1Jq8rCOH9wdo=
+github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/ipfs/go-cid v0.0.2 h1:tuuKaZPU1M6HcejsO3AcYWW8sZ8MTvyxfc4uqB4eFE8=
 github.com/ipfs/go-cid v0.0.2/go.mod h1:GHWU/WuQdMPmIosc4Yn1bcCT7dSeX4lBafM7iqUPQvM=
@@ -75,16 +83,33 @@ github.com/spacemonkeygo/spacelog v0.0.0-20180420211403-2296661a0572 h1:RC6RW7j+
 github.com/spacemonkeygo/spacelog v0.0.0-20180420211403-2296661a0572/go.mod h1:w0SWMsp6j9O/dk4/ZpIhL+3CkG8ofA2vuv7k+ltqUMc=
 github.com/spaolacci/murmur3 v1.1.0 h1:7c1g84S4BPRrfL5Xrdp6fOJ206sU9y293DDHaoy0bLI=
 github.com/spaolacci/murmur3 v1.1.0/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
+go.opencensus.io v0.21.0 h1:mU6zScU4U1YAFPHEHYk+3JC4SY7JxgkqS10ZOSyksNg=
+go.opencensus.io v0.21.0/go.mod h1:mSImk1erAIZhrmZN+AvHh14ztQfjbGwt4TtuofqLduU=
 golang.org/x/crypto v0.0.0-20170930174604-9419663f5a44/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190211182817-74369b46fc67/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90PveolxSbWFaJdECFbxSq0Mqo2M=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190426145343-a29dc8fdc734 h1:p/H982KKEjUnLJkM3tt/LemDnOc1GiZL5FCVlORJ5zo=
 golang.org/x/crypto v0.0.0-20190426145343-a29dc8fdc734/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20190618222545-ea8f1a30c443 h1:IcSOAf4PyMp3U3XbIEj1/xJ2BjNN2jWv7JoyOsMxXUU=
 golang.org/x/crypto v0.0.0-20190618222545-ea8f1a30c443/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
+golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
+golang.org/x/lint v0.0.0-20190227174305-5b3e6a55c961/go.mod h1:wehouNa3lNwaWXcvxsM5YxQ5yQlVC4a0KAMCusXpPoU=
+golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190213061140-3a22650c66bd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a h1:oWX7TPOiFAMXLq8o0ikBYfCJVlRHBcsciT5bXOrH628=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3 h1:0GoQqolDA55aaLxZyTzK/Y2ePZzZTUrRacwib7cNsYQ=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190219092855-153ac476189d h1:Z0Ahzd7HltpJtjAHHxX8QFP3j1yYgiuvjbjRzDj/KH0=
@@ -94,9 +119,17 @@ golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20180221164845-07fd8470d635 h1:2eB4G6bDQDeP69ZXbOKC00S2Kf6TIiRS+DzfKsKeQU0=
 golang.org/x/tools v0.0.0-20180221164845-07fd8470d635/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20190114222345-bf090417da8b/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20190226205152-f727befe758c/go.mod h1:9Yl7xja0Znq3iFh3HoIrodX9oNMXvdceNzlUR8zjMvY=
+google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
+google.golang.org/genproto v0.0.0-20190307195333-5fe7a883aa19/go.mod h1:VzzqZJRnGkLBvHegQrXjBqPurQTc5/KpmUdxsrq26oE=
+google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/fsnotify.v1 v1.4.7/go.mod h1:Tz8NjZHkW78fSQdbUxIjBTcgA1z1m8ZHf0WmKUhAMys=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWDmTeBkI65Dw0HsyUHuEVlX15mw=
 gopkg.in/yaml.v2 v2.2.1 h1:mUhvW9EsL+naU5Q3cakzfE91YhliOondGd6ZrsDBHQE=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=

metrics/register.go

+package metrics
+
+import (
+	"fmt"
+	"sync"
+
+	"go.opencensus.io/stats/view"
+)
+
+var registeredViews = map[string][]*view.View{}
+var mu = new(sync.Mutex)
+
+type ErrNamespace struct {
+	Namespace string
+}
+
+// ErrUnregisteredNamespace is an error for lookup of requested unregistered Namespace
+type ErrUnregisteredNamespace ErrNamespace
+
+func (e ErrUnregisteredNamespace) Error() string {
+	return fmt.Sprintf("no views found registered under Namespace %s", e.Namespace)
+}
+
+// ErrDuplicateNamespaceRegistration is an error for a Namespace that has already
+// registered views
+type ErrDuplicateNamespaceRegistration ErrNamespace
+
+func (e ErrDuplicateNamespaceRegistration) Error() string {
+	return fmt.Sprintf("duplicate registration of views by Namespace %s", e.Namespace)
+}
+
+// RegisterViews accepts a namespace and a slice of Views, which will be registered
+// with opencensus and maintained in the global registered views map
+func RegisterViews(namespace string, views ...*view.View) error {
+	mu.Lock()
+	defer mu.Unlock()
+	_, ok := registeredViews[namespace]
+	if ok {
+		return ErrDuplicateNamespaceRegistration{Namespace: namespace}
+	} else {
+		registeredViews[namespace] = views
+	}
+
+	return nil
+}
+
+// LookupViews returns all views for a Namespace name. Returns an error if the
+// Namespace has not been registered.
+func LookupViews(name string) ([]*view.View, error) {
+	mu.Lock()
+	defer mu.Unlock()
+	views, ok := registeredViews[name]
+	if !ok {
+		return nil, ErrUnregisteredNamespace{Namespace: name}
+	}
+	response := make([]*view.View, len(views))
+	copy(response, views)
+	return response, nil
+}
+
+// AllViews returns all registered views as a single slice
+func AllViews() []*view.View {
+	var views []*view.View
+	mu.Lock()
+	defer mu.Unlock()
+	for _, vs := range registeredViews {
+		views = append(views, vs...)
+	}
+	return views
+}

metrics/register_test.go

+package metrics
+
+import (
+	"fmt"
+	"go.opencensus.io/stats"
+	"testing"
+
+	"go.opencensus.io/stats/view"
+)
+
+func newTestMeasure(name string) stats.Measure {
+	return stats.Int64(fmt.Sprintf("test/measure/%s", name),
+		fmt.Sprintf("Test measurement %s", name),
+		stats.UnitDimensionless,
+	)
+}
+
+func newTestView(name string) *view.View {
+	return &view.View{
+		Name:        fmt.Sprintf("test/%s", name),
+		Description: fmt.Sprintf("Test view %s", name),
+		Measure:     newTestMeasure(name),
+		Aggregation: view.LastValue(),
+	}
+}
+
+func TestRegisteringViews(t *testing.T) {
+	registeredViews = make(map[string][]*view.View)
+
+	t.Run("test registering first views", func(t *testing.T) {
+		testView := newTestView("empty-map-0")
+
+		if err := RegisterViews("test", testView); err != nil {
+			t.Fatal("unable to register view in empty map", err)
+		}
+	})
+
+	t.Run("test registering with existing views", func(t *testing.T) {
+		testView := newTestView("empty-map-1")
+		testView2 := newTestView("existing-entity-0")
+
+		if err := RegisterViews("test2", testView); err != nil {
+			t.Fatal("unable to register view in empty map", err)
+		}
+		if err := RegisterViews("test3", testView2); err != nil {
+			t.Fatal("unable to register view in map", err)
+		}
+	})
+
+	t.Run("test registering duplicate views", func(t *testing.T) {
+		testView := newTestView("empty-map-2")
+		testView2 := newTestView("existing-entity-1")
+
+		if err := RegisterViews("test4", testView); err != nil {
+			t.Fatal("unable to register view in empty map", err)
+		}
+		if err := RegisterViews("test4", testView2); err == nil {
+			t.Fatal("allowed duplicate view registration")
+		}
+	})
+
+	t.Run("test looking up views", func(t *testing.T) {
+		testView := newTestView("empty-map-3")
+
+		if err := RegisterViews("test5", testView); err != nil {
+			t.Fatal("unable to register view in empty map", err)
+		}
+
+		views, err := LookupViews("test5")
+		if err != nil {
+			t.Fatal("error looking up views", err)
+		}
+
+		if views[0].Name != testView.Name {
+			t.Fatal("incorrect view lookup, received name:", views[0].Name)
+		}
+	})
+}
+
+func TestAllViews(t *testing.T) {
+	registeredViews = make(map[string][]*view.View)
+	t.Run("test retrieving all views", func(t *testing.T) {
+		views := []*view.View{newTestView("all-views-0"), newTestView("all-views-1"), newTestView("all-views-2")}
+
+		if err := RegisterViews("test6", views...); err != nil {
+			t.Fatal("unable to register multiple views at once", err)
+		}
+
+		allViews := AllViews()
+		if len(allViews) != len(views) {
+			t.Fatalf("didn't receive equal number of views: %d %d", len(views), len(allViews))
+		}
+	})
+}