Translate exception messages

news/200.bugfix

@@ -0,0 +1 @@
+Translate exception message if it is an instance of zope.i18nmessageid.Message. @davisagli

src/plone/rest/errors.py

@@ -14,6 +14,8 @@
 from zope.component import queryMultiAdapter
 from zope.component import queryUtility
 from zope.component.hooks import getSite
+from zope.i18n import translate
+from zope.i18nmessageid import Message
 
 import json
 import sys
@@ -60,7 +62,12 @@ def __call__(self):
 
     def render_exception(self, exception):
         name = type(exception).__name__
-        message = str(exception)
+        try:
+            message = exception.args[0]
+        except IndexError:
+            message = str(exception)
+        if isinstance(message, Message):
+            message = translate(message, context=self.request)
         result = {"type": name, "message": message}
 
         policy = queryMultiAdapter((self.context, self.request), ICORSPolicy)

src/plone/rest/testing.py

@@ -5,6 +5,7 @@
 from plone.rest.service import Service
 from plone.testing import zope
 from zope.configuration import xmlconfig
+from zope.i18nmessageid import Message
 
 
 class PloneRestLayer(PloneSandboxLayer):
@@ -29,12 +30,4 @@ def setUpZope(self, app, configurationContext):
 
 class InternalServerErrorService(Service):
     def __call__(self):
-        from urllib.error import HTTPError
-
-        raise HTTPError(
-            "http://nohost/plone/500-internal-server-error",
-            500,
-            "InternalServerError",
-            {},
-            None,
-        )
+        raise Exception(Message("Error", domain="plone"))

src/plone/rest/tests/test_error_handling.py

@@ -103,12 +103,8 @@ def test_500_internal_server_error(self):
             + "the server should respond with sending back application/json.",
         )
         self.assertTrue(json.loads(response.content))
-        self.assertEqual("HTTPError", response.json()["type"])
-
-        self.assertEqual("HTTPError", response.json()["type"])
-        self.assertEqual(
-            "HTTP Error 500: InternalServerError", response.json()["message"]
-        )
+        self.assertEqual("Exception", response.json()["type"])
+        self.assertEqual("Error", response.json()["message"])
         self.assertEqual(self.portal_url, response.json()["context"])
 
     def test_500_traceback_only_for_manager_users(self):
@@ -133,3 +129,21 @@ def test_500_traceback_only_for_manager_users(self):
         self.assertRegex(
             traceback[0], r'^File "[^"]*", line \d*, in (publish|transaction_pubevents)'
         )
+
+    def test_500_message_translated(self):
+        registry = self.portal.portal_registry
+        registry["plone.available_languages"] = ["de", "en"]
+        registry["plone.default_language"] = "de"
+        transaction.commit()
+
+        response = requests.get(
+            self.portal_url + "/500-internal-server-error",
+            headers={"Accept": "application/json"},
+        )
+
+        self.assertEqual(response.status_code, 500)
+        self.assertEqual(
+            response.headers.get("Content-Type"),
+            "application/json",
+        )
+        self.assertEqual(response.json()["message"], "Fehler")