stable/freqtrade/rpc/api_server.py

import logging
import threading
from ipaddress import IPv4Address
from typing import Dict

from arrow import Arrow
from flask import Flask, jsonify, request
from flask.json import JSONEncoder

from freqtrade.__init__ import __version__
from freqtrade.rpc.rpc import RPC, RPCException

logger = logging.getLogger(__name__)


class ArrowJSONEncoder(JSONEncoder):
    def default(self, obj):
        try:
            if isinstance(obj, Arrow):
                return obj.for_json()
            iterable = iter(obj)
        except TypeError:
            pass
        else:
            return list(iterable)
        return JSONEncoder.default(self, obj)


class ApiServer(RPC):
    """
    This class runs api server and provides rpc.rpc functionality to it

    This class starts a none blocking thread the api server runs within
    """

    def safe_rpc(func):

        def func_wrapper(self, *args, **kwargs):

            try:
                return func(self, *args, **kwargs)
            except RPCException as e:
                logger.exception("API Error calling %s: %s", func.__name__, e)
                return self.rest_error(f"Error querying {func.__name__}: {e}")

        return func_wrapper

    def __init__(self, freqtrade) -> None:
        """
        Init the api server, and init the super class RPC
        :param freqtrade: Instance of a freqtrade bot
        :return: None
        """
        super().__init__(freqtrade)

        self._config = freqtrade.config
        self.app = Flask(__name__)

        self.app.json_encoder = ArrowJSONEncoder

        # Register application handling
        self.register_rest_other()
        self.register_rest_rpc_urls()

        thread = threading.Thread(target=self.run, daemon=True)
        thread.start()

    def cleanup(self) -> None:
        logger.info("Stopping API Server")
        # TODO: Gracefully shutdown - right now it'll fail on /reload_conf
        # since it's not terminated correctly.

    def send_msg(self, msg: Dict[str, str]) -> None:
        """
        We don't push to endpoints at the moment.
        Take a look at webhooks for that functionality.
        """
        pass

    def rest_dump(self, return_value):
        """ Helper function to jsonify object for a webserver """
        return jsonify(return_value)

    def rest_error(self, error_msg):
        return jsonify({"error": error_msg}), 502

    def register_rest_other(self):
        """
        Registers flask app URLs that are not calls to functionality in rpc.rpc.
        :return:
        """
        self.app.register_error_handler(404, self.page_not_found)

    def register_rest_rpc_urls(self):
        """
        Registers flask app URLs that are calls to functonality in rpc.rpc.

        First two arguments passed are /URL and 'Label'
        Label can be used as a shortcut when refactoring
        :return:
        """
        # Actions to control the bot
        self.app.add_url_rule('/start', 'start', view_func=self._start, methods=['POST'])
        self.app.add_url_rule('/stop', 'stop', view_func=self._stop, methods=['POST'])
        self.app.add_url_rule('/stopbuy', 'stopbuy', view_func=self._stopbuy, methods=['POST'])
        self.app.add_url_rule('/reload_conf', 'reload_conf', view_func=self._reload_conf,
                              methods=['POST'])
        # Info commands
        self.app.add_url_rule('/balance', 'balance', view_func=self._balance, methods=['GET'])
        self.app.add_url_rule('/count', 'count', view_func=self._count, methods=['GET'])
        self.app.add_url_rule('/daily', 'daily', view_func=self._daily, methods=['GET'])
        self.app.add_url_rule('/edge', 'edge', view_func=self._edge, methods=['GET'])
        self.app.add_url_rule('/profit', 'profit', view_func=self._profit, methods=['GET'])
        self.app.add_url_rule('/performance', 'performance', view_func=self._performance,
                              methods=['GET'])
        self.app.add_url_rule('/status', 'status', view_func=self._status, methods=['GET'])
        self.app.add_url_rule('/version', 'version', view_func=self._version, methods=['GET'])

        # Combined actions and infos
        self.app.add_url_rule('/blacklist', 'blacklist', view_func=self._blacklist,
                              methods=['GET', 'POST'])
        self.app.add_url_rule('/whitelist', 'whitelist', view_func=self._whitelist,
                              methods=['GET'])
        self.app.add_url_rule('/forcebuy', 'forcebuy', view_func=self._forcebuy, methods=['POST'])
        self.app.add_url_rule('/forcesell', 'forcesell', view_func=self._forcesell,
                              methods=['POST'])

        # TODO: Implement the following
        # help (?)

    def run(self):
        """ Method that runs flask app in its own thread forever.
        Section to handle configuration and running of the Rest server
        also to check and warn if not bound to a loopback, warn on security risk.
        """
        rest_ip = self._config['api_server']['listen_ip_address']
        rest_port = self._config['api_server']['listen_port']

        logger.info('Starting HTTP Server at {}:{}'.format(rest_ip, rest_port))
        if not IPv4Address(rest_ip).is_loopback:
            logger.warning("SECURITY WARNING - Local Rest Server listening to external connections")
            logger.warning("SECURITY WARNING - This is insecure please set to your loopback,"
                           "e.g 127.0.0.1 in config.json")

        # Run the Server
        logger.info('Starting Local Rest Server')
        try:
            self.app.run(host=rest_ip, port=rest_port)
        except Exception:
            logger.exception("Api server failed to start, exception message is:")
        logger.info('Starting Local Rest Server_end')

    def page_not_found(self, error):
        """
        Return "404 not found", 404.
        """
        return self.rest_dump({
            'status': 'error',
            'reason': '''There's no API call for %s''' % request.base_url,
            'code': 404
        }), 404

    def _start(self):
        """
        Handler for /start.
        Starts TradeThread in bot if stopped.
        """
        msg = self._rpc_start()
        return self.rest_dump(msg)

    def _stop(self):
        """
        Handler for /stop.
        Stops TradeThread in bot if running
        """
        msg = self._rpc_stop()
        return self.rest_dump(msg)

    def _stopbuy(self):
        """
        Handler for /stopbuy.
        Sets max_open_trades to 0 and gracefully sells all open trades
        """
        msg = self._rpc_stopbuy()
        return self.rest_dump(msg)

    def _version(self):
        """
        Prints the bot's version
        """
        return self.rest_dump({"version": __version__})

    def _reload_conf(self):
        """
        Handler for /reload_conf.
        Triggers a config file reload
        """
        msg = self._rpc_reload_conf()
        return self.rest_dump(msg)

    @safe_rpc
    def _count(self):
        """
        Handler for /count.
        Returns the number of trades running
        """
        msg = self._rpc_count()
        return self.rest_dump(msg)

    @safe_rpc
    def _daily(self):
        """
        Returns the last X days trading stats summary.

        :return: stats
        """
        timescale = request.args.get('timescale', 7)
        timescale = int(timescale)

        stats = self._rpc_daily_profit(timescale,
                                       self._config['stake_currency'],
                                       self._config['fiat_display_currency']
                                       )

        return self.rest_dump(stats)

    @safe_rpc
    def _edge(self):
        """
        Returns information related to Edge.
        :return: edge stats
        """
        stats = self._rpc_edge()

        return self.rest_dump(stats)

    @safe_rpc
    def _profit(self):
        """
        Handler for /profit.

        Returns a cumulative profit statistics
        :return: stats
        """
        logger.info("LocalRPC - Profit Command Called")

        stats = self._rpc_trade_statistics(self._config['stake_currency'],
                                           self._config['fiat_display_currency']
                                           )

        return self.rest_dump(stats)

    @safe_rpc
    def _performance(self):
        """
        Handler for /performance.

        Returns a cumulative performance statistics
        :return: stats
        """
        logger.info("LocalRPC - performance Command Called")

        stats = self._rpc_performance()

        return self.rest_dump(stats)

    @safe_rpc
    def _status(self):
        """
        Handler for /status.

        Returns the current status of the trades in json format
        """
        results = self._rpc_trade_status()
        return self.rest_dump(results)

    @safe_rpc
    def _balance(self):
        """
        Handler for /balance.

        Returns the current status of the trades in json format
        """
        results = self._rpc_balance(self._config.get('fiat_display_currency', ''))
        return self.rest_dump(results)

    @safe_rpc
    def _whitelist(self):
        """
        Handler for /whitelist.
        """
        results = self._rpc_whitelist()
        return self.rest_dump(results)

    @safe_rpc
    def _blacklist(self):
        """
        Handler for /blacklist.
        """
        add = request.json.get("blacklist", None) if request.method == 'POST' else None
        results = self._rpc_blacklist(add)
        return self.rest_dump(results)

    @safe_rpc
    def _forcebuy(self):
        """
        Handler for /forcebuy.
        """
        asset = request.json.get("pair")
        price = request.json.get("price", None)
        trade = self._rpc_forcebuy(asset, price)
        return self.rest_dump(trade.to_json())

    @safe_rpc
    def _forcesell(self):
        """
        Handler for /forcesell.
        """
        tradeid = request.json.get("tradeid")
        results = self._rpc_forcesell(tradeid)
        return self.rest_dump(results)