Add recover for panics from handlers

This allows the error to actually propagate back to the client instead of the ominous "exit code 2" and having to search through the daemon logs to see what happened. Signed-off-by: Brian Goff <[email protected]>
Azure · Jan 29, 2025 · e14f4b1 · e14f4b1
1 parent 2b949b2
commit e14f4b1
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/frontend/mux.go b/frontend/mux.go
@@ -536,7 +536,13 @@ func (d *clientWithCustomOpts) CurrentFrontend() (*llb.State, error) {
 
 // Handler returns a [gwclient.BuildFunc] that uses the mux to route requests to appropriate handlers
 func (m *BuildMux) Handler(opts ...func(context.Context, gwclient.Client, *BuildMux) error) gwclient.BuildFunc {
-	return func(ctx context.Context, client gwclient.Client) (*gwclient.Result, error) {
+	return func(ctx context.Context, client gwclient.Client) (_ *gwclient.Result, retErr error) {
+		defer func() {
+			if r := recover(); r != nil {
+				retErr = errors.Errorf("recovered panic in handler: %+v", r)
+			}
+		}()
+
 		if !SupportsDiffMerge(client) {
 			dalec.DisableDiffMerge(true)
 		}