smarter error types

errnowebsocketrequest.go

@@ -13,6 +13,11 @@ func (e ErrNoWebSocketRequest) Error() string {
 	return fmt.Sprintf("no WebSocket request received from %v", e.Addr)
 }
 
+func (e ErrNoWebSocketRequest) Is(target error) (yes bool) {
+	_, yes = target.(ErrNoWebSocketRequest)
+	return
+}
+
 func newErrNoWebSocketRequest(rq *Request) error {
 	return ErrNoWebSocketRequest{Addr: rq.remoteIP}
 }

errpendingcancelled.go

@@ -0,0 +1,36 @@
+package jaws
+
+import (
+	"fmt"
+)
+
+type ErrPendingCancelled struct {
+	JawsKey uint64
+	Cause   error
+	Initial string
+}
+
+func (e ErrPendingCancelled) Error() string {
+	return fmt.Sprintf("Request<%s>:%s %v", JawsKeyString(e.JawsKey), e.Initial, e.Cause)
+}
+
+func (e ErrPendingCancelled) Is(target error) (yes bool) {
+	_, yes = target.(ErrPendingCancelled)
+	return
+}
+
+func (e ErrPendingCancelled) Unwrap() error {
+	return e.Cause
+}
+
+func newErrPendingCancelled(rq *Request, cause error) (err error) {
+	var initial string
+	if rq.Initial != nil {
+		initial = fmt.Sprintf(" %s %q:", rq.Initial.Method, rq.Initial.RequestURI)
+	}
+	return ErrPendingCancelled{
+		JawsKey: rq.JawsKey,
+		Cause:   cause,
+		Initial: initial,
+	}
+}

jaws.go

@@ -549,15 +549,14 @@ func (jw *Jaws) unsubscribe(msgCh chan Message) {
 	}
 }
 
-func errPendingCancelled(rq *Request, deadline time.Time) error {
-	err := context.Cause(rq.ctx)
-	if err == nil {
-		if rq.Created.After(deadline) {
-			return nil
-		}
+func maybeErrPendingCancelled(rq *Request, deadline time.Time) (err error) {
+	if err = context.Cause(rq.ctx); err == nil && rq.Created.Before(deadline) {
 		err = newErrNoWebSocketRequest(rq)
 	}
-	return err
+	if err != nil {
+		err = newErrPendingCancelled(rq, err)
+	}
+	return
 }
 
 func (jw *Jaws) maintenance(requestTimeout time.Duration) {
@@ -567,17 +566,9 @@ func (jw *Jaws) maintenance(requestTimeout time.Duration) {
 	jw.mu.RLock()
 	now := time.Now()
 	deadline := now.Add(-requestTimeout)
-	logger := jw.Logger
 	for _, rq := range jw.pending {
-		if err := errPendingCancelled(rq, deadline); err != nil {
+		if err := jw.Log(maybeErrPendingCancelled(rq, deadline)); err != nil {
 			killReqs = append(killReqs, rq)
-			if logger != nil {
-				var uri string
-				if rq.Initial != nil {
-					uri = fmt.Sprintf("%s %q: ", rq.Initial.Method, rq.Initial.RequestURI)
-				}
-				logger.Printf("cancelled pending %v: %s%v", rq, uri, err)
-			}
 		}
 	}
 	for k, sess := range jw.sessions {

jaws_test.go

@@ -281,7 +281,11 @@ func TestJaws_CleansUpUnconnected(t *testing.T) {
 				elem.SetInner("foo")
 			}
 		}
-		expectLen++
+		err := maybeErrPendingCancelled(rq, deadline)
+		if err == nil {
+			t.Fatal("expected error")
+		}
+		expectLen += len(err.Error() + "\n")
 	}
 	is.Equal(jw.Pending(), numReqs)
 
@@ -304,8 +308,8 @@ func TestJaws_CleansUpUnconnected(t *testing.T) {
 	case <-jw.Done():
 	}
 	w.Flush()
-	s := b.String()
-	if x := strings.Count(s, "\n"); x != expectLen {
+	if x := b.Len(); x != expectLen {
+		t.Log(b.String())
 		is.Equal(b.Len(), expectLen)
 	}
 }

request_test.go

@@ -708,3 +708,18 @@ func TestRequest_IncomingClick(t *testing.T) {
 	default:
 	}
 }
+
+func TestRequest_CustomErrors(t *testing.T) {
+	is := testHelper{t}
+	rq := newTestRequest()
+	defer rq.Close()
+	cause := newErrNoWebSocketRequest(rq.Request)
+	err := newErrPendingCancelled(rq.Request, cause)
+	is.True(errors.Is(err, ErrPendingCancelled{}))
+	is.True(errors.Is(err, ErrNoWebSocketRequest{}))
+	is.Equal(errors.Is(cause, ErrPendingCancelled{}), false)
+	var target1 ErrNoWebSocketRequest
+	is.True(errors.As(err, &target1))
+	var target2 ErrPendingCancelled
+	is.Equal(errors.As(cause, &target2), false)
+}