temporary_did.py 文件源码

def list_expired_temporary_dids(rse, limit, worker_number=None, total_workers=None,
                                session=None):
    """
    List expired temporary DIDs.

    :param rse: the rse name.
    :param limit: The maximum number of replicas returned.
    :param worker_number:      id of the executing worker.
    :param total_workers:      Number of total workers.
    :param session: The database session in use.

    :returns: a list of dictionary replica.
    """
    rse_id = get_rse_id(rse, session=session)
    is_none = None
    query = session.query(models.TemporaryDataIdentifier.scope,
                          models.TemporaryDataIdentifier.name,
                          models.TemporaryDataIdentifier.path,
                          models.TemporaryDataIdentifier.bytes).\
        with_hint(models.TemporaryDataIdentifier, "INDEX(tmp_dids TMP_DIDS_EXPIRED_AT_IDX)", 'oracle').\
        filter(case([(models.TemporaryDataIdentifier.expired_at != is_none, models.TemporaryDataIdentifier.rse_id), ]) == rse_id)

    if worker_number and total_workers and total_workers - 1 > 0:
        if session.bind.dialect.name == 'oracle':
            bindparams = [bindparam('worker_number', worker_number - 1), bindparam('total_workers', total_workers - 1)]
            query = query.filter(text('ORA_HASH(name, :total_workers) = :worker_number', bindparams=bindparams))
        elif session.bind.dialect.name == 'mysql':
            query = query.filter(text('mod(md5(name), %s) = %s' % (total_workers - 1, worker_number - 1)))
        elif session.bind.dialect.name == 'postgresql':
            query = query.filter(text('mod(abs((\'x\'||md5(path))::bit(32)::int), %s) = %s' % (total_workers - 1, worker_number - 1)))

    return [{'path': path,
             'rse': rse,
             'rse_id': rse_id,
             'scope': scope,
             'name': name,
             'bytes': bytes}
            for scope, name, path, bytes in query.limit(limit)]