admin: warn about missing roles in site import (#41252)

tests/test_admin_pages.py

@@ -4577,6 +4577,16 @@ def test_settings_export_import(pub, studio):
     filelist = zipf.namelist()
     assert len([x for x in filelist if 'roles/' in x]) == 0
 
+    # check an error is displayed if such an import is then used and roles are
+    # missing.
+    FormDef.wipe()
+    Workflow.wipe()
+    Role.wipe()
+    resp = app.get('/backoffice/settings/import')
+    resp.form['file'] = Upload('export.wcs', zip_content.getvalue())
+    resp = resp.form.submit('submit')
+    assert 'Unknown referenced role (qux)' in resp
+
 
 def test_settings_themes(pub):
     create_superuser(pub)

wcs/admin/settings.py

@@ -54,7 +54,7 @@ from wcs.qommon import ident
 
 from wcs.formdef import FormDef
 from wcs.carddef import CardDef
-from wcs.workflows import Workflow
+from wcs.workflows import Workflow, WorkflowImportError
 from wcs.roles import Role
 
 from wcs.backoffice.studio import StudioDirectory
@@ -998,6 +998,10 @@ class SettingsDirectory(QommonSettingsDirectory):
                 results = self.import_submit(form)
             except zipfile.BadZipfile:
                 results = None
+                reason = _('Not a valid export file')
+            except WorkflowImportError as e:
+                results = None
+                reason = _(e) % e.msg_args
             html_top('settings', title = _('Import'))
             r = TemplateIO(html=True)
             r += htmltext('<h2>%s</h2>') % _('Import')
@@ -1024,7 +1028,7 @@ class SettingsDirectory(QommonSettingsDirectory):
                     r += htmltext('<li>%d %s</li>') % (results['wscalls'], _('webservice calls'))
                 r += htmltext('</ul>')
             else:
-                r += htmltext('<p>%s</p>') % _('Error: Not a valid export file')
+                r += htmltext('<p>%s %s</p>') % (_('Error:'), reason)
             r += htmltext('<a href=".">%s</a>') % _('Back')
             return r.getvalue()