Adds basic register logic

- Adds register endpoint in the API
- Adds the Gatekeeper to keep track of registered user and allow/reject access
- Adds registration errors
- Updates API unit tests
- Refactors some methods of the API to reduce code replication

teos/api.py

@@ -2,10 +2,11 @@ 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
 
 
@@ -14,6 +15,24 @@ 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.
@@ -24,9 +43,48 @@ class API:
         watcher (:obj:`Watcher <teos.watcher.Watcher>`): a ``Watcher`` instance to pass the requests to.
     """
 
-    def __init__(self, inspector, watcher):
+    # 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):
         """
@@ -43,15 +101,10 @@ class API:
         """
 
         # 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")
+        remote_addr = get_remote_addr()
 
         logger.info("Received add_appointment request", from_addr="{}".format(remote_addr))
 
-        # FIXME: Logging every request so we can get better understanding of bugs in the alpha
-        logger.debug("Request details", data="{}".format(request.data))
-
         if request.is_json:
             # Check content type once if properly defined
             request_data = request.get_json()
@@ -59,9 +112,6 @@ class API:
                 request_data.get("appointment"), request_data.get("signature"), request_data.get("public_key")
             )
 
-            error = None
-            response = None
-
             if type(appointment) == Appointment:
                 appointment_added, signature = self.watcher.add_appointment(appointment)
 
@@ -72,29 +122,26 @@ class API:
                 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 = None
+            response = {"error": error}
 
-        logger.info(
-            "Sending response and disconnecting", from_addr="{}".format(remote_addr), response=response, error=error
-        )
-
-        if error is None:
+        logger.info("Sending response and disconnecting", from_addr="{}".format(remote_addr), response=response)
         return jsonify(response), rcode
-        else:
-            return jsonify({"error": error}), rcode
 
     # FIXME: THE NEXT TWO API ENDPOINTS ARE FOR TESTING AND SHOULD BE REMOVED / PROPERLY MANAGED BEFORE PRODUCTION!
     # ToDo: #17-add-api-keys
@@ -116,9 +163,7 @@ class API:
         """
 
         # 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")
+        remote_addr = get_remote_addr()
 
         locator = request.args.get("locator")
         response = []
@@ -182,12 +227,14 @@ class API:
 
         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"]),

teos/errors.py

@@ -1,4 +1,4 @@
-# Appointment errors
+# Appointment errors [-1, -64]
 APPOINTMENT_EMPTY_FIELD = -1
 APPOINTMENT_WRONG_FIELD_TYPE = -2
 APPOINTMENT_WRONG_FIELD_SIZE = -3
@@ -8,6 +8,10 @@ APPOINTMENT_FIELD_TOO_BIG = -6
 APPOINTMENT_WRONG_FIELD = -7
 APPOINTMENT_INVALID_SIGNATURE = -8
 
+# Registration errors [-65, -128]
+REGISTRATION_MISSING_FIELD = -65
+REGISTRATION_WRONG_FIELD_FORMAT = -66
+
 # Custom RPC errors
 RPC_TX_REORGED_AFTER_BROADCAST = -98
 

teos/gatekeeper.py

@@ -0,0 +1,32 @@
+import re
+
+SUBSCRIPTION_SLOTS = 100
+
+# TODO: UNITTEST
+class Gatekeeper:
+    def __init__(self):
+        self.registered_users = {}
+
+    @staticmethod
+    def check_user_pk(user_pk):
+        """
+        Checks if a given value is a 33-byte hex encoded string.
+
+        Args:
+            user_pk(:mod:`str`): the value to be checked.
+
+        Returns:
+            :obj:`bool`: Whether or not the value matches the format.
+        """
+        return isinstance(user_pk, str) and re.match(r"^[0-9A-Fa-f]{66}$", user_pk) is not None
+
+    def add_update_user(self, user_pk):
+        if not self.check_user_pk(user_pk):
+            raise ValueError("provided public key does not match expected format (33-byte hex string)")
+
+        if user_pk not in self.registered_users:
+            self.registered_users[user_pk] = SUBSCRIPTION_SLOTS
+        else:
+            self.registered_users[user_pk] += SUBSCRIPTION_SLOTS
+
+        return self.registered_users[user_pk]

teos/teosd.py

@@ -17,6 +17,7 @@ from teos.carrier import Carrier
 from teos.inspector import Inspector
 from teos.responder import Responder
 from teos.db_manager import DBManager
+from teos.gatekeeper import Gatekeeper
 from teos.chain_monitor import ChainMonitor
 from teos.block_processor import BlockProcessor
 from teos.tools import can_connect_to_bitcoind, in_correct_network
@@ -150,7 +151,7 @@ def main(command_line_conf):
             # Fire the API and the ChainMonitor
             # FIXME: 92-block-data-during-bootstrap-db
             chain_monitor.monitor_chain()
-            API(Inspector(block_processor, config.get("MIN_TO_SELF_DELAY")), watcher).start()
+            API(Inspector(block_processor, config.get("MIN_TO_SELF_DELAY")), watcher, Gatekeeper()).start()
         except Exception as e:
             logger.error("An error occurred: {}. Shutting down".format(e))
             exit(1)

test/teos/unit/test_api.py

@@ -10,6 +10,7 @@ from teos.watcher import Watcher
 from teos.tools import bitcoin_cli
 from teos.inspector import Inspector
 from teos.responder import Responder
+from teos.gatekeeper import Gatekeeper
 from teos.chain_monitor import ChainMonitor
 
 from test.teos.unit.conftest import (
@@ -55,7 +56,9 @@ def run_api(db_manager, carrier, block_processor):
     watcher.awake()
     chain_monitor.monitor_chain()
 
-    api_thread = Thread(target=API(Inspector(block_processor, config.get("MIN_TO_SELF_DELAY")), watcher).start)
+    api_thread = Thread(
+        target=API(Inspector(block_processor, config.get("MIN_TO_SELF_DELAY")), watcher, Gatekeeper()).start
+    )
     api_thread.daemon = True
     api_thread.start()