Add forgive_all to enable experimental builders.

scripts/slave/gatekeeper_ng.py

 #!/usr/bin/env python
 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Closes tree if configured masters have failed tree-closing steps.
 
 Given a list of masters, gatekeeper_ng will get a list of the latest builds from
 the specified masters. It then checks if any tree-closing steps have failed, and
 if so closes the tree and emails appropriate parties. Configuration for which
@@ skipping 247 matching lines @@
     tools/chromium-build/+/master/gatekeeper_mailer.py, but the list is
   reproduced here:
 
     %(result)s: 'warning' or 'failure'
     %(projectName): 'Chromium', 'Chromium Perf', etc.
     %(builder): the builder name
     %(reason): reason for launching the build
     %(revision): build revision
     %(buildnumber): buildnumber
 
+  'forgive_all' converts all closing_steps to be forgiving_steps. Since
+  forgiving_steps only email sheriffs + watchlist (not the committer), this is a
+  great way to set up experimental or informational builders without spamming
+  people. It is enabled by providing the string 'true'.
+
   The 'comment' key can be put anywhere and is ignored by the parser.
 
   # Python, not JSON.
   {
     'masters': {
       'http://build.chromium.org/p/chromium.win': [
         {
           'sheriff_classes': ['sheriff_win'],
           'tree_notify': ['a_watcher@chromium.org'],
           'categories': ['win_extra'],
@@ skipping 24 matching lines @@
     }
   }
 
   In this case, XP Tests (1) would be flattened down to:
     closing_steps: ['startup_test', 'win_tests']
     forgiving_steps: ['archive', 'boot_windows']
     tree_notify: ['xp_watchers@chromium.org', 'win_watchers@chromium.org',
                   'a_watcher@chromium.org']
     sheriff_classes: ['sheriff_win', 'sheriff_win_test', 'sheriff_xp']
 
-  Again, fields are optional and treated as empty lists/sets if not present.
+  Again, fields are optional and treated as empty lists/sets/strings if not
+  present.
   """
 
   # Keys which are allowed in a master or builder section.
-  master_keys = ['sheriff_classes', 'tree_notify', 'subject_template']
-  builder_keys = ['forgiving_steps', 'closing_steps', 'tree_notify',
-                  'sheriff_classes', 'subject_template']
+  master_keys = ['forgive_all', 'tree_notify', 'sheriff_classes',
+                 'subject_template']
+  builder_keys = ['closing_steps', 'forgiving_steps', 'forgive_all',
+                  'sheriff_classes', 'subject_template', 'tree_notify']
 
 
   # These keys are strings instead of sets. Strings can't be merged,
   # so more specific (master -> category -> builder) strings clobber
   # more generic ones.
-  strings = ['subject_template']
+  strings = ['forgive_all', 'subject_template']
 
   with open(filename) as f:
     raw_gatekeeper_config = json.load(f)
 
   allowed_keys(raw_gatekeeper_config, 'categories', 'masters')
 
   categories = raw_gatekeeper_config.get('categories', {})
   masters = raw_gatekeeper_config.get('masters', {})
 
   for category in categories.values():
@@ skipping 53 matching lines @@
               gatekeeper_builder[k] |= set(categories[c].get(k, []))
 
         # Add in any builder-specific values.
         for k in builder_keys:
           if k in strings:
             if k in builder:
               gatekeeper_builder[k] = builder[k]
           else:
             gatekeeper_builder[k] |= set(builder.get(k, []))
 
+        # Builder postprocessing.
+        if gatekeeper_builder['forgive_all'] == 'true':
+          gatekeeper_builder['forgiving_steps'] |= gatekeeper_builder[
+              'closing_steps']
+          gatekeeper_builder['closing_steps'] = set([])
+
   return gatekeeper_config
 
 
 def parse_sheriff_file(url):
   """Given a sheriff url, download and parse the appropirate sheriff list."""
   with closing(urllib2.urlopen(url)) as f:
     line = f.readline()
   usernames_matcher_ = re.compile(r'document.write\(\'([\w, ]+)\'\)')
   usernames_match = usernames_matcher_.match(line)
   sheriffs = set()
@@ skipping 315 matching lines @@
                         options.disable_domain_filter)
 
   if not options.skip_build_db_update:
     save_build_db(build_db, options.build_db)
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main())