# Stem Docs

## Comparing Directory Authority Flags

Compares the votes of two directory authorities, in this case moria1 and maatuska, with a special interest in the ‘Running’ flag.

    import collections

    import stem.descriptor
    import stem.descriptor.remote
    import stem.directory

    # Query all authority votes asynchronously.

    downloader = stem.descriptor.remote.DescriptorDownloader(
      document_handler = stem.descriptor.DocumentHandler.DOCUMENT,
    )

    # An ordered dictionary ensures queries are finished in the order they were
    # added.

    queries = collections.OrderedDict()

    for name, authority in stem.directory.Authority.from_cache().items():
      if authority.v3ident is None:
        continue  # authority doesn't vote if it lacks a v3ident

      queries[name] = downloader.get_vote(authority)

    # Wait for the votes to finish being downloaded, this produces a dictionary of
    # authority nicknames to their vote.

    votes = dict((name, query.run()[0]) for (name, query) in queries.items())

    # Get a superset of all the fingerprints in all the votes.

    all_fingerprints = set()

    for vote in votes.values():
      all_fingerprints.update(vote.routers.keys())

    # Finally, compare moria1's votes to maatuska's votes.

    for fingerprint in all_fingerprints:
      moria1_vote = votes['moria1'].routers.get(fingerprint)
      maatuska_vote = votes['maatuska'].routers.get(fingerprint)

      if not moria1_vote and not maatuska_vote:
        print("both moria1 and maatuska haven't voted about %s" % fingerprint)
      elif not moria1_vote:
        print("moria1 hasn't voted about %s" % fingerprint)
      elif not maatuska_vote:
        print("maatuska hasn't voted about %s" % fingerprint)
      elif 'Running' in moria1_vote.flags and 'Running' not in maatuska_vote.flags:
        print("moria1 has the Running flag but maatuska doesn't: %s" % fingerprint)
      elif 'Running' in maatuska_vote.flags and 'Running' not in moria1_vote.flags:
        print("maatuska has the Running flag but moria1 doesn't: %s" % fingerprint)

    % python compare_flags.py
    maatuska has the Running flag but moria1 doesn't: 92FCB6748A40E6088E22FBAB943AB2DD743EA818
    maatuska has the Running flag but moria1 doesn't: 6871F682350BA931838C0EC1E4A23044DAE06A73
    maatuska has the Running flag but moria1 doesn't: E2BB13AA2F6960CD93ABE5257A825687F3973C62
    moria1 has the Running flag but maatuska doesn't: 546C54E2A89D88E0794D04AECBF1AC8AC9DA81DE
    moria1 has the Running flag but maatuska doesn't: DCAEC3D069DC39AAE43D13C8AF31B5645E05ED61
    ...