Adds Prometheus metrics (#98)

* Added status metrics in integration test

* Check for status after waiting time

* added electionID labels to metrics

* added unit tests to election status metrics

* added ballots and shuffling metrics

* fix metrics naming

* init metrics in integration tests

* cannot run integration tests in parallel

* cannot test metrics in parallel integration tests

* tested shuffling instances

* added PubShares metrics

* use gauge for ballots counting

* remove conflict

* dont use dkg status for now

* refactor after review

* use a gauge for PromElectionPubShares

Author: jbsv

contracts/evoting/evoting.go

@@ -1,8 +1,10 @@
 package evoting
 
 import (
+	dvoting "github.com/dedis/d-voting"
 	"github.com/dedis/d-voting/contracts/evoting/types"
 	"github.com/dedis/d-voting/services/dkg"
+	"github.com/prometheus/client_golang/prometheus"
 	"go.dedis.ch/dela/core/access"
 	"go.dedis.ch/dela/core/execution"
 	"go.dedis.ch/dela/core/execution/native"
@@ -19,6 +21,36 @@ import (
 	_ "github.com/dedis/d-voting/contracts/evoting/json"
 )
 
+var (
+	PromElectionStatus = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+		Name: "dvoting_status",
+		Help: "status of election",
+	},
+		[]string{"election"},
+	)
+
+	PromElectionBallots = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+		Name: "dvoting_ballots_total",
+		Help: "number of cast ballots",
+	},
+		[]string{"election"},
+	)
+
+	PromElectionShufflingInstances = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+		Name: "dvoting_shufflings_total",
+		Help: "number of shuffling instances",
+	},
+		[]string{"election"},
+	)
+
+	PromElectionPubShares = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+		Name: "dvoting_pubshares_total",
+		Help: "published public shares",
+	},
+		[]string{"election"},
+	)
+)
+
 const (
 	// ElectionsMetadataKey is the key at which election metadata are saved in
 	// the storage.
@@ -216,3 +248,11 @@ func (c Contract) Execute(snap store.Snapshot, step execution.Step) error {
 
 	return nil
 }
+
+func init() {
+	dvoting.PromCollectors = append(dvoting.PromCollectors,
+		PromElectionStatus,
+		PromElectionBallots,
+		PromElectionShufflingInstances,
+		PromElectionPubShares)
+}

contracts/evoting/mod.go

@@ -10,6 +10,7 @@ import (
 	"github.com/dedis/d-voting/contracts/evoting/types"
 	"github.com/dedis/d-voting/internal/testing/fake"
 	"github.com/dedis/d-voting/services/dkg"
+	"github.com/prometheus/client_golang/prometheus/testutil"
 	"github.com/stretchr/testify/require"
 	"go.dedis.ch/dela/core/access"
 	"go.dedis.ch/dela/core/execution"
@@ -109,6 +110,8 @@ func TestExecute(t *testing.T) {
 }
 
 func TestCommand_CreateElection(t *testing.T) {
+	initMetrics()
+
 	fakeActor := fakeDkgActor{
 		publicKey: suite.Point(),
 		err:       nil,
@@ -167,13 +170,16 @@ func TestCommand_CreateElection(t *testing.T) {
 	require.True(t, ok)
 
 	require.Equal(t, types.Initial, election.Status)
+	require.Equal(t, float64(types.Initial), testutil.ToFloat64(PromElectionStatus))
 }
 
 func TestCommand_OpenElection(t *testing.T) {
 	// TODO
 }
 
 func TestCommand_CastVote(t *testing.T) {
+	initMetrics()
+
 	castVote := types.CastVote{
 		ElectionID: fakeElectionID,
 		UserID:     "dummyUserId",
@@ -298,11 +304,13 @@ func TestCommand_CastVote(t *testing.T) {
 	require.Len(t, election.Suffragia.Ciphervotes, 1)
 	require.True(t, castVote.Ballot.Equal(election.Suffragia.Ciphervotes[0]))
 
-	require.Equal(t, castVote.UserID,
-		election.Suffragia.UserIDs[0])
+	require.Equal(t, castVote.UserID, election.Suffragia.UserIDs[0])
+	require.Equal(t, float64(len(election.Suffragia.Ciphervotes)), testutil.ToFloat64(PromElectionBallots))
 }
 
 func TestCommand_CloseElection(t *testing.T) {
+	initMetrics()
+
 	closeElection := types.CloseElection{
 		ElectionID: fakeElectionID,
 		UserID:     "dummyUserId",
@@ -349,6 +357,7 @@ func TestCommand_CloseElection(t *testing.T) {
 	err = cmd.closeElection(snap, makeStep(t, ElectionArg, string(data)))
 	require.EqualError(t, err, fmt.Sprintf("the election is not open, "+
 		"current status: %d", types.Initial))
+	require.Equal(t, 0, testutil.CollectAndCount(PromElectionStatus))
 
 	dummyElection.Status = types.Open
 
@@ -372,6 +381,7 @@ func TestCommand_CloseElection(t *testing.T) {
 
 	err = cmd.closeElection(snap, makeStep(t, ElectionArg, string(data)))
 	require.NoError(t, err)
+	require.Equal(t, float64(types.Closed), testutil.ToFloat64(PromElectionStatus))
 
 	res, err := snap.Get(dummyElectionIDBuff)
 	require.NoError(t, err)
@@ -383,6 +393,7 @@ func TestCommand_CloseElection(t *testing.T) {
 	require.True(t, ok)
 
 	require.Equal(t, types.Closed, election.Status)
+	require.Equal(t, float64(types.Closed), testutil.ToFloat64(PromElectionStatus))
 }
 
 func TestCommand_ShuffleBallotsCannotShuffleTwice(t *testing.T) {
@@ -429,6 +440,8 @@ func TestCommand_ShuffleBallotsCannotShuffleTwice(t *testing.T) {
 }
 
 func TestCommand_ShuffleBallotsValidScenarios(t *testing.T) {
+	initMetrics()
+
 	k := 3
 
 	// Simple Shuffle from round 0 :
@@ -454,6 +467,7 @@ func TestCommand_ShuffleBallotsValidScenarios(t *testing.T) {
 
 	err = cmd.shuffleBallots(snap, step)
 	require.NoError(t, err)
+	require.Equal(t, float64(1), testutil.ToFloat64(PromElectionShufflingInstances))
 
 	// Valid Shuffle is over :
 	shuffleBallots.Round = k
@@ -483,6 +497,7 @@ func TestCommand_ShuffleBallotsValidScenarios(t *testing.T) {
 
 	err = cmd.shuffleBallots(snap, makeStep(t, ElectionArg, string(data)))
 	require.NoError(t, err)
+	require.Equal(t, float64(k+1), testutil.ToFloat64(PromElectionShufflingInstances))
 
 	// Check the shuffle is over:
 	electionTxIDBuff, err := hex.DecodeString(election.ElectionID)
@@ -497,7 +512,8 @@ func TestCommand_ShuffleBallotsValidScenarios(t *testing.T) {
 	election, ok := message.(types.Election)
 	require.True(t, ok)
 
-	require.Equal(t, election.Status, types.ShuffledBallots)
+	require.Equal(t, types.ShuffledBallots, election.Status)
+	require.Equal(t, float64(types.ShuffledBallots), testutil.ToFloat64(PromElectionStatus))
 }
 
 func TestCommand_ShuffleBallotsFormatErrors(t *testing.T) {
@@ -867,6 +883,7 @@ func TestCommand_RegisterPubShares(t *testing.T) {
 
 	err = cmd.registerPubshares(snap, makeStep(t, ElectionArg, string(data)))
 	require.NoError(t, err)
+	require.Equal(t, float64(1), testutil.ToFloat64(PromElectionPubShares))
 
 	// With the public key already used:
 	election.PubsharesUnits.PubKeys = append(election.PubsharesUnits.PubKeys,
@@ -907,6 +924,7 @@ func TestCommand_RegisterPubShares(t *testing.T) {
 
 	err = cmd.registerPubshares(snap, makeStep(t, ElectionArg, string(data)))
 	require.NoError(t, err)
+	require.Equal(t, float64(1), testutil.ToFloat64(PromElectionPubShares))
 
 	res, err := snap.Get(dummyElectionIDBuff)
 	require.NoError(t, err)
@@ -1019,7 +1037,7 @@ func TestCommand_DecryptBallots(t *testing.T) {
 
 	require.Equal(t, types.Ballot{}, election.DecryptedBallots[0])
 	require.Equal(t, types.ResultAvailable, election.Status)
-
+	require.Equal(t, float64(types.ResultAvailable), testutil.ToFloat64(PromElectionStatus))
 }
 
 func TestCommand_CancelElection(t *testing.T) {
@@ -1079,7 +1097,7 @@ func TestCommand_CancelElection(t *testing.T) {
 	require.True(t, ok)
 
 	require.Equal(t, types.Canceled, election.Status)
-
+	require.Equal(t, float64(types.Canceled), testutil.ToFloat64(PromElectionStatus))
 }
 
 func TestRegisterContract(t *testing.T) {
@@ -1089,6 +1107,13 @@ func TestRegisterContract(t *testing.T) {
 // -----------------------------------------------------------------------------
 // Utility functions
 
+func initMetrics() {
+	PromElectionStatus.Reset()
+	PromElectionBallots.Reset()
+	PromElectionShufflingInstances.Reset()
+	PromElectionPubShares.Reset()
+}
+
 func initElectionAndContract() (types.Election, Contract) {
 	fakeDkg := fakeDKG{
 		actor: fakeDkgActor{},