piker/piker/brokers/_util.py

96 lines
2.4 KiB
Python

# piker: trading gear for hackers
# Copyright (C) 2018-present Tyler Goodlet (in stewardship of piker0)
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
"""
Handy utils.
"""
import json
import asks
import logging
from ..log import colorize_json
class BrokerError(Exception):
"Generic broker issue"
class SymbolNotFound(BrokerError):
"Symbol not found by broker search"
class NoData(BrokerError):
'''
Symbol data not permitted or no data
for time range found.
'''
def __init__(
self,
*args,
frame_size: int = 1000,
) -> None:
super().__init__(*args)
# when raised, machinery can check if the backend
# set a "frame size" for doing datetime calcs.
self.frame_size: int = 1000
class DataUnavailable(BrokerError):
'''
Signal storage requests to terminate.
'''
# TODO: add in a reason that can be displayed in the
# UI (for eg. `kraken` is bs and you should complain
# to them that you can't pull more OHLC data..)
class DataThrottle(BrokerError):
'''
Broker throttled request rate for data.
'''
# TODO: add in throttle metrics/feedback
def resproc(
resp: asks.response_objects.Response,
log: logging.Logger,
return_json: bool = True,
log_resp: bool = False,
) -> asks.response_objects.Response:
"""Process response and return its json content.
Raise the appropriate error on non-200 OK responses.
"""
if not resp.status_code == 200:
raise BrokerError(resp.body)
try:
msg = resp.json()
except json.decoder.JSONDecodeError:
log.exception(f"Failed to process {resp}:\n{resp.text}")
raise BrokerError(resp.text)
if log_resp:
log.debug(f"Received json contents:\n{colorize_json(msg)}")
return msg if return_json else resp