def deploy_service_registry_and_set_urls(
    private_keys, web3, contract_manager, service_registry_address
) -> Tuple[ServiceRegistry, List[str]]:
    urls = ["http://foo", "http://boo", "http://coo"]
    c1_client = JSONRPCClient(web3, private_keys[0])
    c1_service_proxy = ServiceRegistry(
        jsonrpc_client=c1_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )
    c2_client = JSONRPCClient(web3, private_keys[1])
    c2_service_proxy = ServiceRegistry(
        jsonrpc_client=c2_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )
    c3_client = JSONRPCClient(web3, private_keys[2])
    c3_service_proxy = ServiceRegistry(
        jsonrpc_client=c3_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )

    # Test that getting a random service for an empty registry returns None
    pfs_address = get_random_service(c1_service_proxy, "latest")
    assert pfs_address is None

    # Test that setting the urls works
    c1_service_proxy.set_url(urls[0])
    c2_service_proxy.set_url(urls[1])
    c3_service_proxy.set_url(urls[2])

    return c1_service_proxy, urls
def db_sync(engine, abs_path, version=None, init_version=0, sanity_check=True):
    """Upgrade or downgrade a database.

    Function runs the upgrade() or downgrade() functions in change scripts.

    :param engine:       SQLAlchemy engine instance for a given database
    :param abs_path:     Absolute path to migrate repository.
    :param version:      Database will upgrade/downgrade until this version.
                         If None - database will update to the latest
                         available version.
    :param init_version: Initial database version
    :param sanity_check: Require schema sanity checking for all tables
    """

    if version is not None:
        try:
            version = int(version)
        except ValueError:
            raise exception.DbMigrationError(
                message=_("version should be an integer"))

    current_version = db_version(engine, abs_path, init_version)
    repository = _find_migrate_repo(abs_path)
    if sanity_check:
        _db_schema_sanity_check(engine)
    if version is None or version > current_version:
        return versioning_api.upgrade(engine, repository, version)
    else:
        return versioning_api.downgrade(engine, repository,
                                        version)