allow unknown endpoints to pass through

internal/server/api.go

@@ -137,12 +137,6 @@ func (a *API) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		updatePR.UpdatedDependencyFiles = replaceBinaryWithHash(updatePR.UpdatedDependencyFiles)
 	}
 
-	if actual == nil {
-		// indicates the kind (endpoint) isn't implemented in decodeWrapper, so return a 501
-		w.WriteHeader(http.StatusNotImplemented)
-		return
-	}
-
 	if kind == "increment_metric" || kind == "record_ecosystem_meta" {
 		// These calls are noisy and changeable; skip recording them in output
 		return
@@ -251,7 +245,9 @@ func decodeWrapper(kind string, data []byte) (actual *model.UpdateWrapper, err e
 	case "increment_metric":
 		actual.Data, err = decode[model.IncrementMetric](data)
 	default:
-		return nil, fmt.Errorf("unexpected output type: %s", kind)
+		// An endpoint the CLI has no model for is still reported to stdout so a
+		// new API endpoint can be exercised before the CLI knows its shape.
+		actual.Data, err = decode[map[string]any](data)
 	}
 	return actual, err
 }

internal/server/api_test.go

@@ -25,15 +25,28 @@ func Test_decodeWrapper(t *testing.T) {
 }
 
 func TestAPI_ServeHTTP(t *testing.T) {
-	t.Run("doesn't crash when unknown endpoint is used", func(t *testing.T) {
-		request := httptest.NewRequest("POST", "/unexpected-endpoint", nil)
+	t.Run("records unknown endpoints instead of rejecting them", func(t *testing.T) {
+		var stdout bytes.Buffer
+		body := `{"data":{"commitSha":"abc123"}}`
+		request := httptest.NewRequest("POST", "/update_jobs/1/unexpected-endpoint", bytes.NewBufferString(body))
 		response := httptest.NewRecorder()
 
-		api := NewAPI(nil, nil)
+		api := NewAPI(nil, &stdout)
+		defer api.Stop()
 		api.ServeHTTP(response, request)
 
-		if response.Code != http.StatusNotImplemented {
-			t.Errorf("expected status code %d, got %d", http.StatusNotImplemented, response.Code)
+		if response.Code != http.StatusOK {
+			t.Errorf("expected status code %d, got %d", http.StatusOK, response.Code)
+		}
+		if len(api.Errors) != 0 {
+			t.Errorf("expected no errors, got %v", api.Errors)
+		}
+		var recorded Wrapper[map[string]any]
+		if err := json.Unmarshal(stdout.Bytes(), &recorded); err != nil {
+			t.Fatal(err)
+		}
+		if recorded.Data["commitSha"] != "abc123" {
+			t.Errorf("expected the payload on stdout, got %v", recorded.Data)
 		}
 	})
 }