buildbot/gerrit_helper.py

# Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Module containing helper class and methods for interacting with Gerrit."""

import constants
import json
import logging

from chromite.buildbot import patch as cros_patch
from chromite.lib import cros_build_lib


class GerritHelper():
  """Helper class to manage interaction with Gerrit server."""
  def __init__(self, internal):
    """Initializes variables for interaction with a gerrit server."""
    if internal:
      ssh_port = constants.GERRIT_INT_PORT
      ssh_host = constants.GERRIT_INT_HOST
    else:
      ssh_port = constants.GERRIT_PORT
      ssh_host = constants.GERRIT_HOST

    self.internal = internal
    self.ssh_prefix = ['ssh', '-p', ssh_port, ssh_host]

  def GetGerritQueryCommand(self, query_list):
    """Returns array corresponding to Gerrit Query command.

    Query is useful for getting information about changelists.  Returns results
    in json format for easy dictionary parsing.  Pass in |query| as the query
    args.
    """
    assert isinstance(query_list, list), 'Query command must be list.'
    return self.ssh_prefix + ['gerrit', 'query', '--format=json'] + query_list

  def GetGerritSqlCommand(self, command_list):
    """Returns array corresponding to Gerrit Review command.

    Review can be used to modify a changelist.  Specifically it can change
    scores, abandon, restore or submit it.  Pass in |command|.
    """
    assert isinstance(command_list, list), 'Sql command must be list.'
    return self.ssh_prefix + ['gerrit', 'gsql'] + command_list

  def GetGerritReviewCommand(self, command_list):
    """Returns array corresponding to Gerrit Review command.

    Review can be used to modify a changelist.  Specifically it can change
    scores, abandon, restore or submit it.  Pass in |command|.
    """
    assert isinstance(command_list, list), 'Review command must be list.'
    return self.ssh_prefix + ['gerrit', 'review'] + command_list


  def GrabChangesReadyForCommit(self):
    """Returns the list of changes to try.

    This methods returns a a list of GerritPatch's to try.
    """
    query_string = ('status:open AND CodeReview=+2 AND Verified=+1 '
                    'AND CommitReady=+1 '
                    'AND NOT CodeReview=-2 AND NOT Verified=-1')

    ready_for_commit = ['--current-patch-set', '"%s"' % query_string]

    query_cmd = self.GetGerritQueryCommand(ready_for_commit)
    raw_results = cros_build_lib.RunCommand(query_cmd,
                                            redirect_stdout=True)

    # Each line returned is a json dict.
    changes_to_commit = []
    for raw_result in raw_results.output.splitlines():
      result_dict = json.loads(raw_result)
      if not 'id' in result_dict:
        logging.debug('No change number found in %s', result_dict)
        continue

      changes_to_commit.append(cros_patch.GerritPatch(result_dict,
                                                      self.internal))

    # Change to commit are ordered in descending order by last update.
    # To be fair it makes sense to do apply changes eldest to newest.
    changes_to_commit.reverse()
    return changes_to_commit

  def GrabPatchFromGerrit(self, project, change, commit):
    """Returns the GerritChange described by the arguments.

    Args:
      project: Name of the Gerrit project for the change.
      change:  The change ID for the change.
      commit:  The specific commit hash for the patch from the review.
    """
    grab_change = (
        ['--current-patch-set',
         '"project:%(project)s AND change:%(change)s AND commit:%(commit)s"' %
             {'project': project, 'change': change, 'commit': commit}
        ])

    query_cmd = self.GetGerritQueryCommand(grab_change)
    raw_results = cros_build_lib.RunCommand(query_cmd,
                                            redirect_stdout=True)

    # First line returned is the json.
    raw_result = raw_results.output.splitlines()[0]
    result_dict = json.loads(raw_result)
    assert result_dict.get('id'), 'Code Review json missing change-id!'
    return cros_patch.GerritPatch(result_dict, self.internal)

  def IsChangeCommitted(self, changeid):
    """Checks to see whether a change is already committed."""
    rev_cmd = self.GetGerritQueryCommand(['change:%s' % changeid])
    raw_results = cros_build_lib.RunCommand(rev_cmd, redirect_stdout=True)
    result_dict = json.loads(raw_results.output.splitlines()[0])
    return result_dict.get('status') not in ['NEW', 'ABANDONED', None]