backoffice: truncate error details in errors_block (#42744)

tests/test_backoffice_pages.py

@@ -5755,10 +5755,15 @@ def test_backoffice_logged_errors(pub):
     resp = resp.form.submit('submit')
     assert LoggedError.count() == 2
 
+    app = login(get_app(pub))
+    resp = app.get('/backoffice/workflows/%s/' % workflow.id)
+    assert 'Failed to evaluate condition' in resp.text
+    assert "error NameError (name 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx…" in resp.text
+
     # remove formdef
     FormDef.wipe()
     resp = resp2.click('Failed to evaluate condition')
-    assert not 'href="http://example.net/backoffice/management/test/' in resp.text
+    assert 'href="http://example.net/backoffice/management/test/' not in resp.text
 
 
 def test_backoffice_formdata_named_wscall(http_requests, pub):

wcs/admin/logged_errors.py

@@ -16,6 +16,7 @@
 
 import re
 
+from django.utils.text import Truncator
 from quixote import get_response, get_publisher, redirect
 from quixote.directory import Directory
 from quixote.html import TemplateIO, htmltext
@@ -180,10 +181,12 @@ class LoggedErrorsDirectory(Directory):
         for error in errors[:3]:
             r += htmltext('<li><a href="logged-errors/%s/">%s</a> ') % (error.id, error.summary)
             if error.exception_class or error.exception_message:
-                r += htmltext(_('error %(class)s (%(message)s)')) % {
+                message = _('error %(class)s (%(message)s)') % {
                     'class': error.exception_class,
                     'message': error.exception_message,
                 }
+                message = Truncator(message).chars(80, truncate='…')
+                r += htmltext(message)
             r += htmltext('</li>')
         if len(errors) > 3:
             r += htmltext('<li>...</li>')