import os import logging from flask import Flask, request, abort, jsonify import teos.errors as errors from teos import HOST, PORT, LOG_PREFIX from common.logger import Logger from common.appointment import Appointment from common.constants import HTTP_OK, HTTP_BAD_REQUEST, HTTP_SERVICE_UNAVAILABLE, LOCATOR_LEN_HEX # ToDo: #5-add-async-to-api app = Flask(__name__) logger = Logger(actor="API", log_name_prefix=LOG_PREFIX) # TODO: UNITTEST def get_remote_addr(): """ Gets the remote client ip address. The HTTP_X_REAL_IP field is tried first in case the server is behind a reverse proxy. Returns: :obj:`str`: the IP address of the client. """ # Getting the real IP if the server is behind a reverse proxy remote_addr = request.environ.get("HTTP_X_REAL_IP") if not remote_addr: remote_addr = request.environ.get("REMOTE_ADDR") return remote_addr class API: """ The :class:`API` is in charge of the interface between the user and the tower. It handles and server user requests. Args: inspector (:obj:`Inspector `): an ``Inspector`` instance to check the correctness of the received data. watcher (:obj:`Watcher `): a ``Watcher`` instance to pass the requests to. """ # TODO: UNITTEST def __init__(self, inspector, watcher, gatekeeper): self.inspector = inspector self.watcher = watcher self.gatekeeper = gatekeeper # TODO: UNITTEST def register(self): remote_addr = get_remote_addr() logger.info("Received register request", from_addr="{}".format(remote_addr)) if request.is_json: request_data = request.get_json() client_pk = request_data.get("public_key") if client_pk: try: rcode = HTTP_OK available_slots = self.gatekeeper.add_update_user(client_pk) response = {"public_key": client_pk, "available_slots": available_slots} except ValueError as e: rcode = HTTP_BAD_REQUEST error = "Error {}: {}".format(errors.REGISTRATION_MISSING_FIELD, str(e)) response = {"error": error} else: rcode = HTTP_BAD_REQUEST error = "Error {}: public_key not found in register message".format( errors.REGISTRATION_WRONG_FIELD_FORMAT ) response = {"error": error} else: rcode = HTTP_BAD_REQUEST error = "appointment rejected. Request is not json encoded" response = {"error": error} logger.info("Sending response and disconnecting", from_addr="{}".format(remote_addr), response=response) return jsonify(response), rcode def add_appointment(self): """ Main endpoint of the Watchtower. The client sends requests (appointments) to this endpoint to request a job to the Watchtower. Requests must be json encoded and contain an ``appointment`` field and optionally a ``signature`` and ``public_key`` fields. Returns: :obj:`tuple`: A tuple containing the response (``json``) and response code (``int``). For accepted appointments, the ``rcode`` is always 0 and the response contains the signed receipt. For rejected appointments, the ``rcode`` is a negative value and the response contains the error message. Error messages can be found at :mod:`Errors `. """ # Getting the real IP if the server is behind a reverse proxy remote_addr = get_remote_addr() logger.info("Received add_appointment request", from_addr="{}".format(remote_addr)) if request.is_json: # Check content type once if properly defined request_data = request.get_json() appointment = self.inspector.inspect( request_data.get("appointment"), request_data.get("signature"), request_data.get("public_key") ) if type(appointment) == Appointment: appointment_added, signature = self.watcher.add_appointment(appointment) if appointment_added: rcode = HTTP_OK response = {"locator": appointment.locator, "signature": signature} else: rcode = HTTP_SERVICE_UNAVAILABLE error = "appointment rejected" response = {"error": error} elif type(appointment) == tuple: rcode = HTTP_BAD_REQUEST error = "appointment rejected. Error {}: {}".format(appointment[0], appointment[1]) response = {"error": error} else: # We should never end up here, since inspect only returns appointments or tuples. Just in case. rcode = HTTP_BAD_REQUEST error = "appointment rejected. Request does not match the standard" response = {"error": error} else: rcode = HTTP_BAD_REQUEST error = "appointment rejected. Request is not json encoded" response = {"error": error} logger.info("Sending response and disconnecting", from_addr="{}".format(remote_addr), response=response) return jsonify(response), rcode # FIXME: THE NEXT TWO API ENDPOINTS ARE FOR TESTING AND SHOULD BE REMOVED / PROPERLY MANAGED BEFORE PRODUCTION! # ToDo: #17-add-api-keys def get_appointment(self): """ Gives information about a given appointment state in the Watchtower. The information is requested by ``locator``. Returns: :obj:`dict`: A json formatted dictionary containing information about the requested appointment. A ``status`` flag is added to the data provided by either the :obj:`Watcher ` or the :obj:`Responder ` that signals the status of the appointment. - Appointments hold by the :obj:`Watcher ` are flagged as ``being_watched``. - Appointments hold by the :obj:`Responder ` are flagged as ``dispute_triggered``. - Unknown appointments are flagged as ``not_found``. """ # Getting the real IP if the server is behind a reverse proxy remote_addr = get_remote_addr() locator = request.args.get("locator") response = [] logger.info("Received get_appointment request", from_addr="{}".format(remote_addr), locator=locator) # ToDo: #15-add-system-monitor if not isinstance(locator, str) or len(locator) != LOCATOR_LEN_HEX: response.append({"locator": locator, "status": "not_found"}) return jsonify(response) locator_map = self.watcher.db_manager.load_locator_map(locator) triggered_appointments = self.watcher.db_manager.load_all_triggered_flags() if locator_map is not None: for uuid in locator_map: if uuid not in triggered_appointments: appointment_data = self.watcher.db_manager.load_watcher_appointment(uuid) if appointment_data is not None: appointment_data["status"] = "being_watched" response.append(appointment_data) tracker_data = self.watcher.db_manager.load_responder_tracker(uuid) if tracker_data is not None: tracker_data["status"] = "dispute_responded" response.append(tracker_data) else: response.append({"locator": locator, "status": "not_found"}) response = jsonify(response) return response def get_all_appointments(self): """ Gives information about all the appointments in the Watchtower. This endpoint should only be accessible by the administrator. Requests are only allowed from localhost. Returns: :obj:`dict`: A json formatted dictionary containing all the appointments hold by the :obj:`Watcher ` (``watcher_appointments``) and by the :obj:`Responder ` (``responder_trackers``). """ # ToDo: #15-add-system-monitor response = None if request.remote_addr in request.host or request.remote_addr == "127.0.0.1": watcher_appointments = self.watcher.db_manager.load_watcher_appointments() responder_trackers = self.watcher.db_manager.load_responder_trackers() response = jsonify({"watcher_appointments": watcher_appointments, "responder_trackers": responder_trackers}) else: abort(404) return response # TODO: UNITTEST def start(self): """ This function starts the Flask server used to run the API. Adds all the routes to the functions listed above. """ routes = { "/register": (self.register, ["POST"]), "/add_appointment": (self.add_appointment, ["POST"]), "/get_appointment": (self.get_appointment, ["GET"]), "/get_all_appointments": (self.get_all_appointments, ["GET"]), } for url, params in routes.items(): app.add_url_rule(url, view_func=params[0], methods=params[1]) # Setting Flask log to ERROR only so it does not mess with out logging. Also disabling flask initial messages logging.getLogger("werkzeug").setLevel(logging.ERROR) os.environ["WERKZEUG_RUN_MAIN"] = "true" app.run(host=HOST, port=PORT)