fix: Add GCP error reporting log format to cloudevent functions and include panic message in stack trace.

.github/workflows/buildpack-integration-test.yml

@@ -25,6 +25,7 @@ jobs:
       prerun: ${{format('testdata/conformance/prerun.sh {0} testdata/conformance/function', github.event_name == 'pull_request' && github.event.pull_request.head.sha || github.sha )}}
       builder-runtime: 'go113'
       builder-runtime-version: '1.13'
+      builder-url: gcr.io/gae-runtimes/buildpacks/google-gae-22/go/builder:latest
   go116-buildpack-test:
     if: github.event.pull_request.head.repo.full_name == github.repository
     uses: GoogleCloudPlatform/functions-framework-conformance/.github/workflows/buildpack-integration-test.yml@main
@@ -36,6 +37,7 @@ jobs:
       prerun:  ${{format('testdata/conformance/prerun.sh {0} testdata/conformance/function', github.event_name == 'pull_request' && github.event.pull_request.head.sha || github.sha )}}
       builder-runtime: 'go116'
       builder-runtime-version: '1.16'
+      builder-url: gcr.io/gae-runtimes/buildpacks/google-gae-22/go/builder:latest
   non-declarative-buildpack-test:
     if: github.event.pull_request.head.repo.full_name == github.repository
     uses: GoogleCloudPlatform/functions-framework-conformance/.github/workflows/buildpack-integration-test.yml@main
@@ -46,4 +48,5 @@ jobs:
       cloudevent-builder-target: 'CloudEvent'
       prerun:  ${{format('testdata/conformance/prerun.sh {0} testdata/conformance/nondeclarative', github.event_name == 'pull_request' && github.event.pull_request.head.sha || github.sha )}}
       builder-runtime: 'go116'
-      builder-runtime-version: '1.16'
+      builder-runtime-version: '1.16'
+      builder-url: gcr.io/gae-runtimes/buildpacks/google-gae-22/go/builder:latest

funcframework/framework.go

@@ -45,21 +45,25 @@ var errorType = reflect.TypeOf((*error)(nil)).Elem()
 // describe what was happening when the panic was encountered, for example
 // "user function execution". w is an http.ResponseWriter to write a generic
 // response body to that does not expose the details of the panic; w can be
-// nil to skip this.
-func recoverPanic(w http.ResponseWriter, panicSrc string) {
+// nil to skip this. If panic needs to be recovered by different caller
+// set shouldPanic to true.
+func recoverPanic(w http.ResponseWriter, panicSrc string, shouldPanic bool) {
 	if r := recover(); r != nil {
 		genericMsg := fmt.Sprintf(panicMessageTmpl, panicSrc)
-		fmt.Fprintf(os.Stderr, "%s\npanic message: %v\nstack trace: \n%s", genericMsg, r, debug.Stack())
+		fmt.Fprintf(os.Stderr, "%s\npanic message: %v\nstack trace: %v\n%s", genericMsg, r, r, debug.Stack())
 		if w != nil {
 			writeHTTPErrorResponse(w, http.StatusInternalServerError, crashStatus, genericMsg)
 		}
+		if shouldPanic {
+			panic(r)
+		}
 	}
 }
 
 // RegisterHTTPFunction registers fn as an HTTP function.
 // Maintained for backward compatibility. Please use RegisterHTTPFunctionContext instead.
 func RegisterHTTPFunction(path string, fn interface{}) {
-	defer recoverPanic(nil, "function registration")
+	defer recoverPanic(nil, "function registration", false)
 
 	fnHTTP, ok := fn.(func(http.ResponseWriter, *http.Request))
 	if !ok {
@@ -76,7 +80,7 @@ func RegisterHTTPFunction(path string, fn interface{}) {
 // Maintained for backward compatibility. Please use RegisterEventFunctionContext instead.
 func RegisterEventFunction(path string, fn interface{}) {
 	ctx := context.Background()
-	defer recoverPanic(nil, "function registration")
+	defer recoverPanic(nil, "function registration", false)
 	if err := RegisterEventFunctionContext(ctx, path, fn); err != nil {
 		panic(fmt.Sprintf("unexpected error in RegisterEventFunctionContext: %v", err))
 	}
@@ -192,7 +196,7 @@ func wrapHTTPFunction(fn func(http.ResponseWriter, *http.Request)) (http.Handler
 			defer fmt.Println()
 			defer fmt.Fprintln(os.Stderr)
 		}
-		defer recoverPanic(w, "user function execution")
+		defer recoverPanic(w, "user function execution", false)
 		fn(w, r)
 	}), nil
 }
@@ -237,7 +241,7 @@ func wrapTypedFunction(fn interface{}) (http.Handler, error) {
 			return
 		}
 
-		defer recoverPanic(w, "user function execution")
+		defer recoverPanic(w, "user function execution", false)
 		funcReturn := reflect.ValueOf(fn).Call([]reflect.Value{
 			argVal.Elem(),
 		})
@@ -286,6 +290,7 @@ func wrapCloudEventFunction(ctx context.Context, fn func(context.Context, cloude
 
 	// Always log errors returned by the function to stderr
 	logErrFn := func(ctx context.Context, ce cloudevents.Event) error {
+		defer recoverPanic(nil, "user function execution", true)
 		err := fn(ctx, ce)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, fmtFunctionError(err))
@@ -345,7 +350,7 @@ func runUserFunctionWithContext(ctx context.Context, w http.ResponseWriter, r *h
 		return
 	}
 
-	defer recoverPanic(w, "user function execution")
+	defer recoverPanic(w, "user function execution", false)
 	userFunErr := reflect.ValueOf(fn).Call([]reflect.Value{
 		reflect.ValueOf(ctx),
 		argVal.Elem(),

funcframework/framework_test.go

@@ -767,6 +767,7 @@ func TestRegisterCloudEventFunctionContext(t *testing.T) {
 			ceHeaders: map[string]string{
 				"Content-Type": "application/cloudevents+json",
 			},
+			wantStderr: fmt.Sprintf(panicMessageTmpl, "user function execution"),
 		},
 		{
 			name: "error returns 500",

go.mod

@@ -3,7 +3,9 @@ module github.com/GoogleCloudPlatform/functions-framework-go
 go 1.11
 
 require (
-	cloud.google.com/go/functions v1.15.4
+	cloud.google.com/go v0.110.8 // indirect
+	cloud.google.com/go/functions v1.15.3
 	github.com/cloudevents/sdk-go/v2 v2.14.0
-	github.com/google/go-cmp v0.6.0
+	github.com/google/go-cmp v0.5.9
+	github.com/google/uuid v1.4.0 // indirect
 )