def parse_subcommand(self, command, **options):
cmd_dict = {}
cmd_name = str_if_bytes(command[0])
cmd_dict["name"] = cmd_name
cmd_dict["arity"] = int(command[1])
cmd_dict["flags"] = [str_if_bytes(flag) for flag in command[2]]
cmd_dict["first_key_pos"] = command[3]
cmd_dict["last_key_pos"] = command[4]
cmd_dict["step_count"] = command[5]
if len(command) > 7:
cmd_dict["tips"] = command[7]
cmd_dict["key_specifications"] = command[8]
cmd_dict["subcommands"] = command[9]
return cmd_dict
def connect_to(self, address):
self.host, self.port = address
super().connect()
if self.connection_pool.check_connection:
self.send_command('PING')
if str_if_bytes(self.read_response()) != 'PONG':
raise ConnectionError('PING failed')
def _get_pubsub_keys(self, *args):
"""
Get the keys from pubsub command.
Although PubSub commands have predetermined key locations, they are not
supported in the 'COMMAND's output, so the key positions are hardcoded
in this method
"""
if len(args) < 2:
# The command has no keys in it
return None
args = [str_if_bytes(arg) for arg in args]
command = args[0].upper()
if command == "PUBSUB":
# the second argument is a part of the command name, e.g.
# ['PUBSUB', 'NUMSUB', 'foo'].
pubsub_type = args[1].upper()
if pubsub_type in ["CHANNELS", "NUMSUB"]:
keys = args[2:]
elif command in [
"SUBSCRIBE", "PSUBSCRIBE", "UNSUBSCRIBE", "PUNSUBSCRIBE"
]:
# format example:
# SUBSCRIBE channel [channel ...]
keys = list(args[1:])
elif command == "PUBLISH":
# format example:
# PUBLISH channel message
keys = [args[1]]
else:
keys = None
return keys
async def connect_to(self, address):
self.host, self.port = address
await super().connect()
if self.connection_pool.check_connection:
await self.send_command("PING")
if str_if_bytes(await self.read_response()) != "PONG":
raise ConnectionError("PING failed")
def get_keys(self, redis_conn, *args):
"""
Get the keys from the passed command.
NOTE: Due to a bug in redis<7.0, this function does not work properly
for EVAL or EVALSHA when the `numkeys` arg is 0.
- issue: https://github.com/redis/redis/issues/9493
- fix: https://github.com/redis/redis/pull/9733
So, don't use this function with EVAL or EVALSHA.
"""
if len(args) < 2:
# The command has no keys in it
return None
cmd_name = args[0].lower()
if cmd_name not in self.commands:
# try to split the command name and to take only the main command,
# e.g. 'memory' for 'memory usage'
cmd_name_split = cmd_name.split()
cmd_name = cmd_name_split[0]
if cmd_name in self.commands:
# save the splitted command to args
args = cmd_name_split + list(args[1:])
else:
# We'll try to reinitialize the commands cache, if the engine
# version has changed, the commands may not be current
self.initialize(redis_conn)
if cmd_name not in self.commands:
raise RedisError(
f"{cmd_name.upper()} command doesn't exist in Redis commands"
)
command = self.commands.get(cmd_name)
if "movablekeys" in command["flags"]:
keys = self._get_moveable_keys(redis_conn, *args)
elif "pubsub" in command["flags"] or command["name"] == "pubsub":
keys = self._get_pubsub_keys(*args)
else:
if (command["step_count"] == 0 and command["first_key_pos"] == 0
and command["last_key_pos"] == 0):
is_subcmd = False
if "subcommands" in command:
subcmd_name = f"{cmd_name}|{args[1].lower()}"
for subcmd in command["subcommands"]:
if str_if_bytes(subcmd[0]) == subcmd_name:
command = self.parse_subcommand(subcmd)
is_subcmd = True
# The command doesn't have keys in it
if not is_subcmd:
return None
last_key_pos = command["last_key_pos"]
if last_key_pos < 0:
last_key_pos = len(args) - abs(last_key_pos)
keys_pos = list(
range(command["first_key_pos"], last_key_pos + 1,
command["step_count"]))
keys = [args[pos] for pos in keys_pos]
return keys
