X-Git-Url: https://wannabe.guru.org/gitweb/?a=blobdiff_plain;f=config.py;h=81bd7d113021b3b66324836804004fdd38beb5aa;hb=4c74ef100038a239bae9b4fd4d61fb04f5b391b4;hp=f3a2dfe3888903543bc07fbcde0d96a423aed81e;hpb=a085dbceac4e911a743c84388b55a0a8f2ba320b;p=python_utils.git diff --git a/config.py b/config.py index f3a2dfe..81bd7d1 100644 --- a/config.py +++ b/config.py @@ -103,6 +103,11 @@ SAVED_MESSAGES: List[str] = [] PROGRAM_NAME: str = os.path.basename(sys.argv[0]) ORIG_ARGV: List[str] = sys.argv.copy() +# A zookeeper client that is lazily created so as to not incur the +# latency of connecting to zookeeper for programs that are not reading +# or writing their config data into zookeeper. +ZK: Optional[KazooClient] = None + class OptionalRawFormatter(argparse.HelpFormatter): """This formatter has the same bahavior as the normal argparse text @@ -325,6 +330,7 @@ def _augment_sys_argv_from_environment_variables(): def _augment_sys_argv_from_loadfile(): """Internal. Augment with arguments persisted in a saved file.""" + global ZK loadfile = None saw_other_args = False grab_next_arg = False @@ -344,20 +350,21 @@ def _augment_sys_argv_from_loadfile(): zkpath = None if loadfile[:3] == 'zk:': try: - zk = KazooClient( - hosts=scott_secrets.ZOOKEEPER_NODES, - use_ssl=True, - verify_certs=False, - keyfile=scott_secrets.ZOOKEEPER_CLIENT_CERT, - keyfile_password=scott_secrets.ZOOKEEPER_CLIENT_PASS, - certfile=scott_secrets.ZOOKEEPER_CLIENT_CERT, - ) - zk.start() + if ZK is None: + ZK = KazooClient( + hosts=scott_secrets.ZOOKEEPER_NODES, + use_ssl=True, + verify_certs=False, + keyfile=scott_secrets.ZOOKEEPER_CLIENT_CERT, + keyfile_password=scott_secrets.ZOOKEEPER_CLIENT_PASS, + certfile=scott_secrets.ZOOKEEPER_CLIENT_CERT, + ) + ZK.start() zkpath = loadfile[3:] if not zkpath.startswith('/config/'): zkpath = '/config/' + zkpath zkpath = re.sub(r'//+', '/', zkpath) - if not zk.exists(zkpath): + if not ZK.exists(zkpath): raise Exception( f'ERROR: --config_loadfile argument must be a file, {loadfile} not found (in zookeeper)' ) @@ -380,11 +387,15 @@ def _augment_sys_argv_from_loadfile(): newargs = [] if zkpath: try: - contents = zk.get(zkpath)[0] + assert ZK + contents = ZK.get(zkpath)[0] contents = contents.decode() newargs = [ arg.strip('\n') for arg in contents.split('\n') if 'config_savefile' not in arg ] + size = sys.getsizeof(newargs) + if size > 1024 * 1024: + raise Exception(f'Saved args are too large! ({size} bytes)') except Exception as e: raise Exception(f'Error reading {zkpath} from zookeeper.') from e SAVED_MESSAGES.append(f'Loaded config from zookeeper from {zkpath}') @@ -404,6 +415,7 @@ def parse(entry_module: Optional[str]) -> Dict[str, Any]: global CONFIG_PARSE_CALLED if CONFIG_PARSE_CALLED: return config + global ZK # If we're about to do the usage message dump, put the main # module's argument group last in the list (if possible) so that @@ -452,18 +464,20 @@ def parse(entry_module: Optional[str]) -> Dict[str, Any]: zkpath = '/config/' + zkpath zkpath = re.sub(r'//+', '/', zkpath) try: - zk = KazooClient( - hosts=scott_secrets.ZOOKEEPER_NODES, - use_ssl=True, - verify_certs=False, - keyfile=scott_secrets.ZOOKEEPER_CLIENT_CERT, - keyfile_password=scott_secrets.ZOOKEEPER_CLIENT_PASS, - certfile=scott_secrets.ZOOKEEPER_CLIENT_CERT, - ) - zk.start() - if zk.exists(zkpath): - zk.delete(zkpath) - zk.create(zkpath, data.encode()) + if not ZK: + ZK = KazooClient( + hosts=scott_secrets.ZOOKEEPER_NODES, + use_ssl=True, + verify_certs=False, + keyfile=scott_secrets.ZOOKEEPER_CLIENT_CERT, + keyfile_password=scott_secrets.ZOOKEEPER_CLIENT_PASS, + certfile=scott_secrets.ZOOKEEPER_CLIENT_CERT, + ) + ZK.start() + if not ZK.exists(zkpath): + ZK.create(zkpath, data.encode()) + else: + ZK.set(zkpath, data.encode()) except Exception as e: raise Exception(f'Failed to create zookeeper path {zkpath}') from e SAVED_MESSAGES.append(f'Saved config to zookeeper in {zkpath}')