Add mass-abandon to gerrit_client.py

mass-abandon allows users to mass abandon CLs based on search query.
Owner is always specified (either "me" or user defined via -p).

R=gavinmak@google.com, thakis@chromium.org

Change-Id: I789a3a1f3af22867ebbbc50c35b60486206ff403
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2811005Reviewed-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Josip Sokcevic <sokcevic@google.com>

gerrit_client.py

@@ -225,6 +225,75 @@ def CMDabandon(parser, args):
   write_result(result, opt)
 
 
+@subcommand.usage('''Mass abandon changes
+
+Mass abandon abandons CLs that match search criteria provided by user. Before
+any change is actually abandoned, user is presented with a list of CLs that
+will be affected if user confirms. User can skip confirmation by passing --force
+parameter.
+
+The script can abandon up to 100 CLs per invocation.
+
+Examples:
+gerrit_client.py mass-abandon --host https://HOST -p 'project=repo2'
+gerrit_client.py mass-abandon --host https://HOST -p 'message=testing'
+gerrit_client.py mass-abandon --host https://HOST -p 'is=wip' -p 'age:1y'
+''')
+def CMDmass_abandon(parser, args):
+  parser.add_option('-p',
+                    '--param',
+                    dest='params',
+                    action='append',
+                    default=[],
+                    help='repeatable query parameter, format: -p key=value')
+  parser.add_option('-m', '--message', default='', help='reason for abandoning')
+  parser.add_option('-f',
+                    '--force',
+                    action='store_true',
+                    help='Don\'t prompt for confirmation')
+
+  opt, args = parser.parse_args(args)
+
+  for p in opt.params:
+    assert '=' in p, '--param is key=value, not "%s"' % p
+  search_query = list(tuple(p.split('=', 1)) for p in opt.params)
+  if not any(t for t in search_query if t[0] == 'owner'):
+    # owner should always be present when abandoning changes
+    search_query.append(('owner', 'me'))
+  search_query.append(('status', 'open'))
+  logging.info("Searching for: %s" % search_query)
+
+  host = urlparse.urlparse(opt.host).netloc
+
+  result = gerrit_util.QueryChanges(
+      host,
+      search_query,
+      # abandon at most 100 changes as not all Gerrit instances support
+      # unlimited results.
+      limit=100,
+  )
+  if len(result) == 0:
+    logging.warn("Nothing to abandon")
+    return
+
+  logging.warn("%s CLs match search query: " % len(result))
+  for change in result:
+    logging.warn("[ID: %d] %s" % (change['_number'], change['subject']))
+
+  if not opt.force:
+    q = raw_input(
+        'Do you want to move forward with abandoning? [y to confirm] ').strip()
+    if q not in ['y', 'Y']:
+      logging.warn("Aborting...")
+      return
+
+  for change in result:
+    logging.warning("Abandoning: %s" % change['subject'])
+    gerrit_util.AbandonChange(host, change['id'], opt.message)
+
+  logging.warning("Done")
+
+
 class OptionParser(optparse.OptionParser):
   """Creates the option parse and add --verbose support."""
   def __init__(self, *args, **kwargs):