Open Source Monorail

appengine/monorail/framework/artifactcollision.py

Index: appengine/monorail/framework/artifactcollision.py
diff --git a/appengine/monorail/framework/artifactcollision.py b/appengine/monorail/framework/artifactcollision.py
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+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is govered by a BSD-style
+# license that can be found in the LICENSE file or at
+# https://developers.google.com/open-source/licenses/bsd
+
+"""Class that implements the artifact update collision page.
+
+This page is displayed only when one user views and edits an issue,
+but another user has already submitted an issue update before the
+first user submits his/her update.
+
+TODO(jrobbins): give the user better options on how to proceed.
+
+Summary of classes:
+  ArtifactCollision: Show an error message explaining the mid-air collision.
+"""
+
+import re
+
+from framework import monorailrequest
+from framework import servlet
+
+
+class ArtifactCollision(servlet.Servlet):
+  """ArtifactCollision page explains that a mid-air collision has occured."""
+
+  _PAGE_TEMPLATE = 'framework/artifact-collision-page.ezt'
+  _MAIN_TAB_MODE = servlet.Servlet.MAIN_TAB_NONE
+
+  def GatherPageData(self, mr):
+    """Build up a dictionary of data values to use when rendering the page.
+
+    Args:
+      mr: commonly used info parsed from the request.
+
+    Returns:
+      A dict of values used by EZT for rendering the page.
+    """
+    artifact_name = mr.GetParam('name')
+    if not artifact_name:
+      raise monorailrequest.InputException()  # someone forged a link
+
+    artifact_detail_url = '/p/%s/issues/detail?id=%s' % (
+        mr.project_name, mr.continue_issue_id)
+
+    return {
+        'artifact_name': artifact_name,
+        'artifact_detail_url': artifact_detail_url,
+    }