wrote postmaster

postmaster_test.go

@@ -0,0 +1,208 @@
+package prism
+
+import (
+	"context"
+	// "git.wisehodl.dev/jay/go-mana-component"
+	"github.com/stretchr/testify/assert"
+	// "sync/atomic"
+	"testing"
+	"time"
+)
+
+func TestPostmasterUnknownPeerSend(t *testing.T) {
+	ctx := context.Background()
+	poolHasPeer := func(id string) (string, bool) { return id, true }
+	poolEvents := make(chan PoolEvent, 4)
+	poolSendFunc := func(id string, data Envelope) error { return nil }
+
+	pm := NewPostmaster(ctx, poolHasPeer, poolEvents, poolSendFunc, nil)
+
+	_, err := pm.Send(ctx, "wss://test", []byte("[]"), func(LetterOutcome) {})
+	assert.Error(t, err)
+}
+
+func TestPostmasterSend(t *testing.T) {
+	ctx := context.Background()
+	poolHasPeer := func(id string) (string, bool) { return id, true }
+	poolEvents := make(chan PoolEvent, 4)
+	poolSendFunc := func(id string, data Envelope) error { return nil }
+
+	pm := NewPostmaster(ctx, poolHasPeer, poolEvents, poolSendFunc, nil)
+
+	poolEvents <- PoolEvent{
+		ID: "wss://test", Kind: EventAdded, At: time.Now()}
+	poolEvents <- PoolEvent{
+		ID: "wss://test", Kind: EventConnected, At: time.Now()}
+
+	Eventually(t, func() bool { return len(pm.Peers()) > 0 },
+		"should add peer")
+
+	called := make(chan LetterOutcome, 1)
+	_, err := pm.Send(
+		ctx, "wss://test", []byte("[]"), func(o LetterOutcome) { called <- o })
+	assert.NoError(t, err)
+
+	var outcome LetterOutcome
+	Eventually(t, func() bool {
+		select {
+		default:
+			return false
+		case outcome = <-called:
+			return true
+		}
+	}, "should have received outcome")
+
+	assert.Equal(t, OutcomeSent, outcome.Kind)
+}
+
+func TestPostmasterPeerRemoved(t *testing.T) {
+	ctx := context.Background()
+	poolHasPeer := func(id string) (string, bool) { return id, true }
+	poolEvents := make(chan PoolEvent, 4)
+	poolSendFunc := func(id string, data Envelope) error { return nil }
+
+	pm := NewPostmaster(ctx, poolHasPeer, poolEvents, poolSendFunc, nil)
+
+	// add peer, but do not connect
+	poolEvents <- PoolEvent{
+		ID: "wss://test", Kind: EventAdded, At: time.Now()}
+	Eventually(t, func() bool { return len(pm.Peers()) > 0 },
+		"should add peer")
+
+	// send two letters
+	outcomes := make([]LetterOutcome, 0, 2)
+	called := make(chan LetterOutcome, 2)
+	_, err := pm.Send(
+		ctx, "wss://test", []byte("[]"), func(o LetterOutcome) { called <- o })
+	assert.NoError(t, err)
+	_, err = pm.Send(
+		ctx, "wss://test", []byte("[]"), func(o LetterOutcome) { called <- o })
+	assert.NoError(t, err)
+
+	// wait for them to hit the courier queue
+	time.Sleep(100 * time.Millisecond)
+
+	// remove the peer
+	poolEvents <- PoolEvent{
+		ID: "wss://test", Kind: EventRemoved, At: time.Now()}
+
+	// expect each letter to return cancelled
+	Eventually(t, func() bool {
+		select {
+		default:
+			return false
+		case o := <-called:
+			outcomes = append(outcomes, o)
+			return len(outcomes) == 2
+		}
+	}, "should have returned 2 outcomes")
+
+	if len(outcomes) >= 2 {
+		assert.Equal(t, OutcomeCancelled, outcomes[0].Kind)
+		assert.Equal(t, OutcomeCancelled, outcomes[1].Kind)
+	}
+
+	// subsequent sends should fail
+	_, err = pm.Send(
+		ctx, "wss://test", []byte("[]"), func(o LetterOutcome) { called <- o })
+	assert.Error(t, err)
+}
+
+func TestPostmasterCourierCloseRace(t *testing.T) {
+	ctx := context.Background()
+	poolHasPeer := func(id string) (string, bool) { return id, true }
+	poolEvents := make(chan PoolEvent, 4)
+	poolSendFunc := func(id string, data Envelope) error { return nil }
+
+	pm := NewPostmaster(ctx, poolHasPeer, poolEvents, poolSendFunc, nil)
+
+	// add peer, but do not connect
+	poolEvents <- PoolEvent{
+		ID: "wss://test", Kind: EventAdded, At: time.Now()}
+	Eventually(t, func() bool { return len(pm.Peers()) > 0 },
+		"should add peer")
+
+	// remove the peer
+	poolEvents <- PoolEvent{
+		ID: "wss://test", Kind: EventRemoved, At: time.Now()}
+
+	// send a letter
+	time.Sleep(5 * time.Microsecond) // small wait lines up the race condition
+	var outcome LetterOutcome
+	called := make(chan LetterOutcome, 1)
+	_, err := pm.Send(
+		ctx, "wss://test", []byte("[]"), func(o LetterOutcome) { called <- o })
+
+	if err != nil {
+		// the close won the race, the letter was not sent
+		return
+	}
+
+	// the letter might beat the courier close and return cancelled
+	Eventually(t, func() bool {
+		select {
+		default:
+			return false
+		case outcome = <-called:
+			return true
+		}
+	}, "should have returned 1 outcomes")
+
+	if outcome.LetterID == 0 {
+		t.Fatal("did not receive an outcome")
+	}
+
+	assert.Equal(t, OutcomeCancelled, outcome.Kind)
+}
+
+func TestPostmasterClose(t *testing.T) {
+	ctx := context.Background()
+	poolHasPeer := func(id string) (string, bool) { return id, true }
+	poolEvents := make(chan PoolEvent, 4)
+	poolSendFunc := func(id string, data Envelope) error { return nil }
+
+	pm := NewPostmaster(ctx, poolHasPeer, poolEvents, poolSendFunc, nil)
+
+	// add peer, but do not connect
+	poolEvents <- PoolEvent{
+		ID: "wss://test", Kind: EventAdded, At: time.Now()}
+	Eventually(t, func() bool { return len(pm.Peers()) > 0 },
+		"should add peer")
+
+	// send two letters
+	outcomes := make([]LetterOutcome, 0, 2)
+	called := make(chan LetterOutcome, 2)
+	_, err := pm.Send(
+		ctx, "wss://test", []byte("[]"), func(o LetterOutcome) { called <- o })
+	assert.NoError(t, err)
+	_, err = pm.Send(
+		ctx, "wss://test", []byte("[]"), func(o LetterOutcome) { called <- o })
+	assert.NoError(t, err)
+
+	// wait for them to hit the courier queue
+	time.Sleep(100 * time.Millisecond)
+
+	// close postmaster
+	pm.Close()
+
+	// expect each letter to return cancelled
+	Eventually(t, func() bool {
+		select {
+		default:
+			return false
+		case o := <-called:
+			outcomes = append(outcomes, o)
+			return len(outcomes) == 2
+		}
+	}, "should have returned 2 outcomes")
+
+	if len(outcomes) >= 2 {
+		assert.Equal(t, OutcomeCancelled, outcomes[0].Kind)
+		assert.Equal(t, OutcomeCancelled, outcomes[1].Kind)
+	}
+
+	// subsequent sends should fail
+	_, err = pm.Send(
+		ctx, "wss://test", []byte("[]"), func(o LetterOutcome) { called <- o })
+	assert.Error(t, err)
+}