internal/jsonrpc2: try to suppress unnecessary errors on shutdown
Even on successful shutdown, test logs contain a lot of "failed reading
header line: EOF". This can be distracting, or worse, misleading. Do our
best to suppress these error logs.
Updates golang/go#39130
Change-Id: I6ebe61100501f69c7490b418f53871b4e9704a00
Reviewed-on: https://go-review.googlesource.com/c/tools/+/237582
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Cottrell <iancottrell@google.com>
diff --git a/internal/jsonrpc2/serve.go b/internal/jsonrpc2/serve.go
index 6d0a9dc..6589ed3 100644
--- a/internal/jsonrpc2/serve.go
+++ b/internal/jsonrpc2/serve.go
@@ -6,7 +6,9 @@
import (
"context"
+ "errors"
"fmt"
+ "io"
"net"
"os"
"time"
@@ -105,7 +107,9 @@
case err := <-doneListening:
return err
case err := <-closedConns:
- event.Error(ctx, "closed a connection", err)
+ if !isClosingError(err) {
+ event.Error(ctx, "closed a connection", err)
+ }
activeConns--
if activeConns == 0 {
connTimer.Reset(idleTimeout)
@@ -117,3 +121,19 @@
}
}
}
+
+// isClosingError reports if the error occurs normally during the process of
+// closing a network connection. It uses imperfect heuristics that err on the
+// side of false negatives, and should not be used for anything critical.
+func isClosingError(err error) bool {
+ if errors.Is(err, io.EOF) {
+ return true
+ }
+ // Per https://github.com/golang/go/issues/4373, this error string should not
+ // change. This is not ideal, but since the worst that could happen here is
+ // some superfluous logging, it is acceptable.
+ if err.Error() == "use of closed network connection" {
+ return true
+ }
+ return false
+}
