fix(messagequeue): no retry after queue shutdown

Previously, we allowed the last message send attempt to run to maxRetries if the queue was shutdown,
which also generated warning logs. Now, if a send attempt fails, check that the queue has shutdown
and immediately return if it has

messagequeue/messagequeue.go

@@ -5,7 +5,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/ipfs/go-block-format"
+	blocks "github.com/ipfs/go-block-format"
 
 	gsmsg "github.com/ipfs/go-graphsync/message"
 	gsnet "github.com/ipfs/go-graphsync/network"
@@ -189,6 +189,8 @@ func (mq *MessageQueue) attemptSendAndRecovery(message gsmsg.GraphSyncMessage) b
 	mq.sender = nil
 
 	select {
+	case <-mq.done:
+		return true
 	case <-mq.ctx.Done():
 		return true
 	case <-time.After(time.Millisecond * 100):

messagequeue/messagequeue_test.go

@@ -2,6 +2,7 @@ package messagequeue
 
 import (
 	"context"
+	"fmt"
 	"math/rand"
 	"reflect"
 	"sync"
@@ -89,6 +90,72 @@ func TestStartupAndShutdown(t *testing.T) {
 	}
 }
 
+func TestShutdownDuringMessageSend(t *testing.T) {
+	ctx := context.Background()
+	ctx, cancel := context.WithTimeout(ctx, 1*time.Second)
+	defer cancel()
+
+	peer := testutil.GeneratePeers(1)[0]
+	messagesSent := make(chan gsmsg.GraphSyncMessage)
+	resetChan := make(chan struct{}, 1)
+	fullClosedChan := make(chan struct{}, 1)
+	messageSender := &fakeMessageSender{
+		fmt.Errorf("Something went wrong"),
+		fullClosedChan,
+		resetChan,
+		messagesSent}
+	var waitGroup sync.WaitGroup
+	messageNetwork := &fakeMessageNetwork{nil, nil, messageSender, &waitGroup}
+
+	messageQueue := New(ctx, peer, messageNetwork)
+	messageQueue.Startup()
+	id := gsmsg.GraphSyncRequestID(rand.Int31())
+	priority := gsmsg.GraphSyncPriority(rand.Int31())
+	selector := testutil.RandomBytes(100)
+	root := testutil.GenerateCids(1)[0]
+
+	// setup a message and advance as far as beginning to send it
+	waitGroup.Add(1)
+	messageQueue.AddRequest(gsmsg.NewRequest(id, root, selector, priority))
+	waitGroup.Wait()
+
+	// now shut down
+	messageQueue.Shutdown()
+
+	// let the message send attempt complete and fail (as it would if
+	// the connection were closed)
+	select {
+	case <-ctx.Done():
+		t.Fatal("message send not attempted")
+	case <-messagesSent:
+	}
+
+	// verify the connection is reset after a failed send attempt
+	select {
+	case <-resetChan:
+	case <-fullClosedChan:
+		t.Fatal("message sender should have been reset but was closed")
+	case <-ctx.Done():
+		t.Fatal("message sender should have been closed but wasn't")
+	}
+
+	// now verify after it's reset, no further retries, connection
+	// resets, or attempts to close the connection, cause the queue
+	// should realize it's shut down and stop processing
+	// FIXME: this relies on time passing -- 100 ms to be exact
+	// and we should instead mock out time as a dependency
+	waitGroup.Add(1)
+	select {
+	case <-messagesSent:
+		t.Fatal("should not have attempted to send second message")
+	case <-resetChan:
+		t.Fatal("message sender should not have been reset again")
+	case <-fullClosedChan:
+		t.Fatal("message sender should not have been closed closed")
+	case <-ctx.Done():
+	}
+}
+
 func TestProcessingNotification(t *testing.T) {
 	ctx := context.Background()
 	ctx, cancel := context.WithTimeout(ctx, 1*time.Second)