fix json-rpc interface (when not using CLI)

electrum/daemon.py

@@ -29,16 +29,16 @@ import time
 import traceback
 import sys
 import threading
-from typing import Dict, Optional, Tuple, Iterable
+from typing import Dict, Optional, Tuple, Iterable, Callable, Union, Sequence, Mapping
 from base64 import b64decode, b64encode
 from collections import defaultdict
 import concurrent
 from concurrent import futures
+import json
 
 import aiohttp
 from aiohttp import web, client_exceptions
 from aiorpcx import TaskGroup
-import json
 
 from . import util
 from .network import Network
@@ -151,6 +151,11 @@ class AuthenticatedServer(Logger):
         self.rpc_user = rpc_user
         self.rpc_password = rpc_password
         self.auth_lock = asyncio.Lock()
+        self._methods = {}  # type: Dict[str, Callable]
+
+    def register_method(self, f):
+        assert f.__name__ not in self._methods, f"name collision for {f.__name__}"
+        self._methods[f.__name__] = f
 
     async def authenticate(self, headers):
         if self.rpc_password == '':
@@ -184,15 +189,21 @@ class AuthenticatedServer(Logger):
             request = json.loads(request)
             method = request['method']
             _id = request['id']
-            params = request.get('params', [])
-            f = getattr(self, method)
-            assert f in self.methods
-        except:
+            params = request.get('params', [])  # type: Union[Sequence, Mapping]
+            if method not in self._methods:
+                raise Exception(f"attempting to use unregistered method: {method}")
+            f = self._methods[method]
+        except Exception as e:
+            self.logger.exception("invalid request")
             return web.Response(text='Invalid Request', status=500)
-        response = {'id':_id}
+        response = {'id': _id}
         try:
-            response['result'] = await f(*params)
+            if isinstance(params, dict):
+                response['result'] = await f(**params)
+            else:
+                response['result'] = await f(*params)
         except BaseException as e:
+            self.logger.exception("internal error while executing RPC")
             response['error'] = str(e)
         return web.json_response(response)
 
@@ -209,13 +220,12 @@ class CommandsServer(AuthenticatedServer):
         self.port = self.config.get('rpcport', 0)
         self.app = web.Application()
         self.app.router.add_post("/", self.handle)
-        self.methods = set()
-        self.methods.add(self.ping)
-        self.methods.add(self.gui)
+        self.register_method(self.ping)
+        self.register_method(self.gui)
         self.cmd_runner = Commands(config=self.config, network=self.daemon.network, daemon=self.daemon)
         for cmdname in known_commands:
-            self.methods.add(getattr(self.cmd_runner, cmdname))
-        self.methods.add(self.run_cmdline)
+            self.register_method(getattr(self.cmd_runner, cmdname))
+        self.register_method(self.run_cmdline)
 
     async def run(self):
         self.runner = web.AppRunner(self.app)
@@ -277,9 +287,8 @@ class WatchTowerServer(AuthenticatedServer):
         self.lnwatcher = network.local_watchtower
         self.app = web.Application()
         self.app.router.add_post("/", self.handle)
-        self.methods = set()
-        self.methods.add(self.get_ctn)
-        self.methods.add(self.add_sweep_tx)
+        self.register_method(self.get_ctn)
+        self.register_method(self.add_sweep_tx)
 
     async def run(self):
         self.runner = web.AppRunner(self.app)