chore(webhook): deprecate Gotenberg-Webhook-Error-Url, make it non-mandatory if Gotenberg-Webhook-Events-Url is set

pkg/modules/webhook/client.go

@@ -39,6 +39,11 @@ type client struct {
 func (c client) send(ctx context.Context, body io.Reader, headers map[string]string, errored bool) error {
 	url := c.url
 	if errored {
+		if c.errorUrl == "" {
+			// No error URL provided; error details will be sent
+			// via the events URL instead.
+			return nil
+		}
 		url = c.errorUrl
 	}
 

pkg/modules/webhook/middleware.go

@@ -105,15 +105,22 @@ func webhookMiddleware(w *Webhook) api.Middleware {
 					ctx := c.Get("context").(*api.Context)
 					cancel := c.Get("cancel").(context.CancelFunc)
 
-					// Do we have a webhook error URL in case of... error?
+					// Do we have a webhook error URL and/or an events URL?
+					// At least one must be provided.
 					webhookErrorUrl := c.Request().Header.Get("Gotenberg-Webhook-Error-Url")
-					if webhookErrorUrl == "" {
+					webhookEventsUrl := c.Request().Header.Get("Gotenberg-Webhook-Events-Url")
+
+					if webhookErrorUrl == "" && webhookEventsUrl == "" {
 						return api.WrapError(
-							errors.New("empty webhook error URL"),
+							errors.New("empty webhook error URL and events URL"),
-							api.NewSentinelHttpError(http.StatusBadRequest, "Invalid 'Gotenberg-Webhook-Error-Url' header: empty value or header not provided"),
+							api.NewSentinelHttpError(http.StatusBadRequest, "At least one of 'Gotenberg-Webhook-Error-Url' or 'Gotenberg-Webhook-Events-Url' headers must be provided"),
 						)
 					}
 
+					if webhookErrorUrl != "" {
+						ctx.Log().Warn("'Gotenberg-Webhook-Error-Url' header is deprecated, use 'Gotenberg-Webhook-Events-Url' instead")
+					}
+
 					deadline, ok := ctx.Deadline()
 					if !ok {
 						return errors.New("context has no deadline")
@@ -126,9 +133,11 @@ func webhookMiddleware(w *Webhook) api.Middleware {
 						return fmt.Errorf("filter webhook URL: %w", err)
 					}
 
-					err = gotenberg.FilterDeadline(w.errorAllowList, w.errorDenyList, webhookErrorUrl, deadline)
+					if webhookErrorUrl != "" {
-					if err != nil {
+						err = gotenberg.FilterDeadline(w.errorAllowList, w.errorDenyList, webhookErrorUrl, deadline)
-						return fmt.Errorf("filter webhook error URL: %w", err)
+						if err != nil {
+							return fmt.Errorf("filter webhook error URL: %w", err)
+						}
 					}
 
 					// Let's check the HTTP methods for calling the webhook URLs.
@@ -164,9 +173,12 @@ func webhookMiddleware(w *Webhook) api.Middleware {
 						return fmt.Errorf("get method to use for webhook: %w", err)
 					}
 
-					webhookErrorMethod, err := methodFromHeader("Gotenberg-Webhook-Error-Method")
+					var webhookErrorMethod string
-					if err != nil {
+					if webhookErrorUrl != "" {
-						return fmt.Errorf("get method to use for webhook error: %w", err)
+						webhookErrorMethod, err = methodFromHeader("Gotenberg-Webhook-Error-Method")
+						if err != nil {
+							return fmt.Errorf("get method to use for webhook error: %w", err)
+						}
 					}
 
 					// What about extra HTTP headers?
@@ -183,8 +195,7 @@ func webhookMiddleware(w *Webhook) api.Middleware {
 						}
 					}
 
-					// What about the events URL?
+					// Filter the events URL if provided.
-					webhookEventsUrl := c.Request().Header.Get("Gotenberg-Webhook-Events-Url")
 					if webhookEventsUrl != "" {
 						err = gotenberg.FilterDeadline(w.allowList, w.denyList, webhookEventsUrl, deadline)
 						if err != nil {

test/integration/features/webhook.feature

@@ -86,3 +86,43 @@ Feature: Webhook
         "timestamp": "ignore"
       }
       """
+
+  Scenario: Webhook Events URL Only (Success)
+    Given I have a default Gotenberg container
+    Given I have a webhook server
+    When I make a "POST" request to Gotenberg at the "/forms/pdfengines/flatten" endpoint with the following form data and header(s):
+      | files                        | testdata/page_1.pdf                           | file   |
+      | Gotenberg-Webhook-Url        | http://host.docker.internal:%d/webhook        | header |
+      | Gotenberg-Webhook-Events-Url | http://host.docker.internal:%d/webhook/events | header |
+    Then the response status code should be 204
+    When I wait for the asynchronous request to the webhook
+    Then the webhook request header "Content-Type" should be "application/pdf"
+    Then there should be 1 PDF(s) in the webhook request
+    Then the webhook event should match JSON:
+      """
+      {
+        "event": "webhook.success",
+        "correlationId": "ignore",
+        "timestamp": "ignore"
+      }
+      """
+
+  Scenario: Webhook Events URL Only (Synchronous)
+    Given I have a Gotenberg container with the following environment variable(s):
+      | WEBHOOK_ENABLE_SYNC_MODE | true |
+    Given I have a webhook server
+    When I make a "POST" request to Gotenberg at the "/forms/pdfengines/flatten" endpoint with the following form data and header(s):
+      | files                        | testdata/page_1.pdf                           | file   |
+      | Gotenberg-Webhook-Url        | http://host.docker.internal:%d/webhook        | header |
+      | Gotenberg-Webhook-Events-Url | http://host.docker.internal:%d/webhook/events | header |
+    Then the response status code should be 204
+    Then the webhook request header "Content-Type" should be "application/pdf"
+    Then there should be 1 PDF(s) in the webhook request
+    Then the webhook event should match JSON:
+      """
+      {
+        "event": "webhook.success",
+        "correlationId": "ignore",
+        "timestamp": "ignore"
+      }
+      """