Integrate event into voter

go.mod

@@ -5,6 +5,7 @@ go 1.20
 require (
 	github.com/dchest/uniuri v1.2.0
 	github.com/go-resty/resty/v2 v2.7.0
+	github.com/gopatchy/event v0.0.0-20230617212132-152b30a10ad7
 	github.com/gopatchy/proxy v0.0.0-20230608062432-7adc14d65656
 	github.com/samber/lo v1.38.1
 	github.com/stretchr/testify v1.8.4

go.sum

@@ -5,6 +5,8 @@ github.com/dchest/uniuri v1.2.0 h1:koIcOUdrTIivZgSLhHQvKgqdWZq5d7KdMEWF1Ud6+5g=
 github.com/dchest/uniuri v1.2.0/go.mod h1:fSzm4SLHzNZvWLvWJew423PhAzkpNQYq+uNLq4kxhkY=
 github.com/go-resty/resty/v2 v2.7.0 h1:me+K9p3uhSmXtrBZ4k9jcEAfJmuC8IivWHwaLZwPrFY=
 github.com/go-resty/resty/v2 v2.7.0/go.mod h1:9PWDzw47qPphMRFfhsyk0NnSgvluHcljSMVIq3w7q0I=
+github.com/gopatchy/event v0.0.0-20230617212132-152b30a10ad7 h1:xSRLvyWogantNY6mybpX+mViJgJZaBmsI4fuyT94N+E=
+github.com/gopatchy/event v0.0.0-20230617212132-152b30a10ad7/go.mod h1:SplGDUsTiPon8FasSqw3eogKiNgHuoV0kHu+jG2E2xo=
 github.com/gopatchy/proxy v0.0.0-20230608062432-7adc14d65656 h1:q1ENffcg6/E0gbraIY39aGZ9To+1vGFxk8ZNbbqD/jI=
 github.com/gopatchy/proxy v0.0.0-20230608062432-7adc14d65656/go.mod h1:k0bdf6Mh7yJIAeO1dogSND27OpXn6w+KS9TUPKUQAHI=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=

lib_test.go

@@ -1,6 +1,7 @@
 package elect_test
 
 import (
+	"context"
 	"net"
 	"net/http"
 	"testing"
@@ -8,6 +9,7 @@ import (
 
 	"github.com/dchest/uniuri"
 	"github.com/gopatchy/elect"
+	"github.com/gopatchy/event"
 	"github.com/gopatchy/proxy"
 	"github.com/samber/lo"
 	"github.com/stretchr/testify/require"
@@ -60,6 +62,11 @@ func (ts *TestServer) Addr() *net.TCPAddr {
 }
 
 func NewTestSystem(t *testing.T, numCandidates, numVoters int) *TestSystem {
+	ctx := context.Background()
+
+	ec := event.New()
+	defer ec.Close()
+
 	ts := &TestSystem{
 		signingKey: uniuri.New(),
 	}
@@ -70,7 +77,7 @@ func NewTestSystem(t *testing.T, numCandidates, numVoters int) *TestSystem {
 
 	for i := 0; i < numVoters; i++ {
 		ts.proxies = append(ts.proxies, proxy.NewProxy(t, ts.Server(0).Addr()))
-		ts.voters = append(ts.voters, elect.NewVoter(ts.Proxy(i).HTTP(), ts.signingKey))
+		ts.voters = append(ts.voters, elect.NewVoter(ctx, ec, ts.Proxy(i).HTTP(), ts.signingKey))
 	}
 
 	return ts

voter.go

@@ -1,6 +1,7 @@
 package elect
 
 import (
+	"context"
 	"crypto/hmac"
 	"encoding/json"
 	"log"
@@ -8,6 +9,7 @@ import (
 
 	"github.com/dchest/uniuri"
 	"github.com/go-resty/resty/v2"
+	"github.com/gopatchy/event"
 	"github.com/samber/lo"
 )
 
@@ -38,7 +40,7 @@ type voteResponse struct {
 	ResponseSent time.Time `json:"responseSent"`
 }
 
-func NewVoter(url string, signingKey string) *Voter {
+func NewVoter(ctx context.Context, ec *event.Client, url string, signingKey string) *Voter {
 	v := &Voter{
 		client: resty.New().
 			SetCloseConnection(true).
@@ -52,7 +54,7 @@ func NewVoter(url string, signingKey string) *Voter {
 		period: maxVotePeriod,
 	}
 
-	go v.loop()
+	go v.loop(ctx, ec)
 
 	return v
 }
@@ -67,17 +69,17 @@ func (v *Voter) Stop() {
 	v.update = nil
 }
 
-func (v *Voter) loop() {
+func (v *Voter) loop(ctx context.Context, ec *event.Client) {
 	defer close(v.done)
 
 	for {
-		if !v.poll() {
+		if !v.poll(ctx, ec) {
 			break
 		}
 	}
 }
 
-func (v *Voter) poll() bool {
+func (v *Voter) poll(ctx context.Context, ec *event.Client) bool {
 	t := time.NewTimer(RandDurationN(v.period))
 	defer t.Stop()
 
@@ -90,10 +92,10 @@ func (v *Voter) poll() bool {
 
 	select {
 	case <-t.C:
-		v.sendVote()
+		v.sendVote(ctx, ec)
 
 	case <-t2.C:
-		v.sendVote()
+		v.sendVote(ctx, ec)
 
 	case period, ok := <-v.update:
 		if !ok {
@@ -106,7 +108,7 @@ func (v *Voter) poll() bool {
 	return true
 }
 
-func (v *Voter) sendVote() {
+func (v *Voter) sendVote(ctx context.Context, ec *event.Client) {
 	v.vote.VoteSent = time.Now().UTC()
 
 	js := lo.Must(json.Marshal(v.vote))
@@ -126,7 +128,10 @@ func (v *Voter) sendVote() {
 	}
 
 	if resp.IsError() {
-		v.log("response: %d", resp.StatusCode())
+		v.log(ctx, ec,
+			"event", "error",
+			"response", resp.StatusCode(),
+		)
 
 		v.vote.NumPollsSinceChange = 0
 
@@ -135,12 +140,20 @@ func (v *Voter) sendVote() {
 
 	sig := resp.Header().Get("Signature")
 	if sig == "" {
-		v.log("missing Signature response header")
+		v.log(ctx, ec,
+			"event", "error",
+			"error", "missing Signature response header",
+		)
+
 		return
 	}
 
 	if !hmac.Equal([]byte(sig), []byte(mac(resp.Body(), v.signingKey))) {
-		v.log("invalid Signature response header")
+		v.log(ctx, ec,
+			"event", "error",
+			"error", "invalid Signature response header",
+		)
+
 		return
 	}
 
@@ -148,12 +161,19 @@ func (v *Voter) sendVote() {
 
 	err = json.Unmarshal(resp.Body(), vr)
 	if err != nil {
-		v.log("invalid response: %s", resp.String())
+		v.log(ctx, ec,
+			"event", "error",
+			"error", err,
+		)
+
 		return
 	}
 
 	if time.Since(vr.ResponseSent).Abs() > 15*time.Second {
-		v.log("excessive time difference (%.1f seconds); delay, replay, or clock skew", time.Since(vr.ResponseSent).Seconds())
+		v.log(ctx, ec,
+			"event", "error",
+			"error", "excessive time difference",
+		)
 	}
 
 	if vr.CandidateID == v.vote.LastSeenCandidateID {
@@ -164,6 +184,9 @@ func (v *Voter) sendVote() {
 	}
 }
 
-func (v *Voter) log(format string, args ...any) {
-	log.Printf("[voter] "+format, args...)
+func (v *Voter) log(ctx context.Context, ec *event.Client, vals ...any) {
+	ec.Log(ctx, append([]any{
+		"library", "elect",
+		"subsystem", "voter",
+	}, vals...)...)
 }