Unify message IDs between network and interfaces

Previously network.py had its own idea of request IDs,
and each interface had its own which was sent on the wire.
The interface would jump through hoops to translate one
to the other.

This unifies them so that a message ID is passed when
queueing a request, in addition to the method and params.
network.py is now solely responsible for message ID management.

Apart from being simpler and clearer, this also should be faster
as there is much less data structure manipulation and rebuilding
happening.

lib/interface.py

@@ -221,7 +221,6 @@ class Interface(util.PrintError):
         self.pipe.set_timeout(0.0)  # Don't wait for data
         # Dump network messages.  Set at runtime from the console.
         self.debug = False
-        self.message_id = 0
         self.unsent_requests = []
         self.unanswered_requests = {}
         # Set last ping to zero to ensure immediate ping
@@ -241,32 +240,26 @@ class Interface(util.PrintError):
             self.socket.shutdown(socket.SHUT_RDWR)
         self.socket.close()
 
-    def queue_request(self, request):
-        '''Queue a request.'''
+    def queue_request(self, *args):  # method, params, _id
+        '''Queue a request, later to be send with send_requests when the
+        socket is available for writing.
+        '''
         self.request_time = time.time()
-        self.unsent_requests.append(request)
+        self.unsent_requests.append(args)
 
     def send_requests(self):
         '''Sends all queued requests.  Returns False on failure.'''
-        def copy_request(orig):
-            # Replace ID after making copy - mustn't change caller's copy
-            request = orig.copy()
-            request['id'] = self.message_id
-            self.message_id += 1
-            if self.debug:
-                self.print_error("-->", request, orig.get('id'))
-            return request
-
-        requests_as_sent = map(copy_request, self.unsent_requests)
+        make_dict = lambda (m, p, i): {'method': m, 'params': p, 'id': i}
+        wire_requests = map(make_dict, self.unsent_requests)
         try:
-            self.pipe.send_all(requests_as_sent)
+            self.pipe.send_all(wire_requests)
         except socket.error, e:
             self.print_error("socket error:", e)
             return False
-        # unanswered_requests stores the original unmodified user
-        # request, keyed by wire ID
-        for n, request in enumerate(self.unsent_requests):
-            self.unanswered_requests[requests_as_sent[n]['id']] = request
+        for request in self.unsent_requests:
+            if self.debug:
+                self.print_error("-->", request)
+            self.unanswered_requests[request[2]] = request
         self.unsent_requests = []
         return True
 
@@ -291,37 +284,39 @@ class Interface(util.PrintError):
 
     def get_responses(self):
         '''Call if there is data available on the socket.  Returns a list of
-        notifications and a list of responses.  The notifications are
-        singleton unsolicited responses presumably as a result of
-        prior subscriptions.  The responses are (request, response)
-        pairs.  If the connection was closed remotely or the remote
-        server is misbehaving, the last notification will be None.
+        (request, response) pairs.  Notifications are singleton
+        unsolicited responses presumably as a result of prior
+        subscriptions, so request is None and there is no 'id' member.
+        Otherwise it is a response, which has an 'id' member and a
+        corresponding request.  If the connection was closed remotely
+        or the remote server is misbehaving, a (None, None) will appear.
         '''
-        notifications, responses = [], []
+        responses = []
         while True:
             try:
                 response = self.pipe.get()
             except util.timeout:
                 break
             if response is None:
-                notifications.append(None)
+                responses.append((None, None))
                 self.closed_remotely = True
                 self.print_error("connection closed remotely")
                 break
             if self.debug:
                 self.print_error("<--", response)
-            wire_id = response.pop('id', None)
-            if wire_id is None:
-                notifications.append(response)
-            elif wire_id in self.unanswered_requests:
-                request = self.unanswered_requests.pop(wire_id)
-                responses.append((request, response))
+            wire_id = response.get('id', None)
+            if wire_id is None:  # Notification
+                responses.append((None, response))
             else:
-                notifications.append(None)
-                self.print_error("unknown wire ID", wire_id)
-                break
+                request = self.unanswered_requests.pop(wire_id, None)
+                if request:
+                    responses.append((request, response))
+                else:
+                    self.print_error("unknown wire ID", wire_id)
+                    responses.append(None, None) # Signal
+                    break
 
-        return notifications, responses
+        return responses
 
 
 def check_cert(host, cert):

lib/network.py

@@ -254,15 +254,26 @@ class Network(util.DaemonThread):
     def is_up_to_date(self):
         return self.unanswered_requests == {}
 
-    def queue_request(self, method, params):
-        self.interface.queue_request({'method': method, 'params': params})
+    def queue_request(self, method, params, interface=None):
+        # If you want to queue a request on any interface it must go
+        # through this function so message ids are properly tracked
+        if interface is None:
+            interface = self.interface
+        message_id = self.message_id
+        self.message_id += 1
+        interface.queue_request(method, params, message_id)
+        return message_id
 
     def send_subscriptions(self):
         # clear cache
         self.cached_responses = {}
         self.print_error('sending subscriptions to', self.interface.server, len(self.unanswered_requests), len(self.subscribed_addresses))
-        for r in self.unanswered_requests.values():
-            self.interface.queue_request(r[0])
+        # Resend unanswered requests
+        requests = self.unanswered_requests.values()
+        self.unanswered_requests = {}
+        for request in requests:
+            message_id = self.queue_request(request[0], request[1])
+            self.unanswered_requests[message_id] = request
         for addr in self.subscribed_addresses:
             self.queue_request('blockchain.address.subscribe', [addr])
         self.queue_request('server.banner', [])
@@ -488,38 +499,39 @@ class Network(util.DaemonThread):
                 callback(response)
 
     def process_responses(self, interface):
-        notifications, responses = interface.get_responses()
+        responses = interface.get_responses()
 
         for request, response in responses:
-            # Client ID was given by the daemon or proxy
-            client_id = request.get('id')
-            if client_id is not None:
-                if interface != self.interface:
-                    continue
-                _req, callback = self.unanswered_requests.pop(client_id)
+            callback = None
+            if request:
+                method, params, message_id = request
+                # client requests go through self.send() with a
+                # callback, are only sent to the current interface,
+                # and are placed in the unanswered_requests dictionary
+                client_req = self.unanswered_requests.pop(message_id, None)
+                if client_req:
+                    assert interface == self.interface
+                    callback = client_req[2]
+                # Copy the request method and params to the response
+                response['method'] = method
+                response['params'] = params
             else:
-                callback = None
-            # Copy the request method and params to the response
-            response['method'] = request.get('method')
-            response['params'] = request.get('params')
-            response['id'] = client_id
+                if not response:  # Closed remotely / misbehaving
+                    self.connection_down(interface.server)
+                    break
+                # Rewrite response shape to match subscription request response
+                method = response.get('method')
+                params = response.get('params')
+                if method == 'blockchain.headers.subscribe':
+                    response['result'] = params[0]
+                    response['params'] = []
+                elif method == 'blockchain.address.subscribe':
+                    response['params'] = [params[0]]  # addr
+                    response['result'] = params[1]
+
+            # Response is now in canonical form
             self.process_response(interface, response, callback)
 
-        for response in notifications:
-            if not response:  # Closed remotely
-                self.connection_down(interface.server)
-                break
-            # Rewrite response shape to match subscription request response
-            method = response.get('method')
-            params = response.get('params')
-            if method == 'blockchain.headers.subscribe':
-                response['result'] = params[0]
-                response['params'] = []
-            elif method == 'blockchain.address.subscribe':
-                response['params'] = [params[0]]  # addr
-                response['result'] = params[1]
-            self.process_response(interface, response, None)
-
     def send(self, messages, callback):
         '''Messages is a list of (method, value) tuples'''
         with self.lock:
@@ -535,16 +547,11 @@ class Network(util.DaemonThread):
                 for sub in subs:
                     if sub not in self.subscriptions[callback]:
                         self.subscriptions[callback].append(sub)
-                _id = self.message_id
-                self.message_id += len(messages)
 
             unsent = []
             for message in messages:
-                method, params = message
-                request = {'id': _id, 'method': method, 'params': params}
-                if not self.process_request(request, callback):
+                if not self.process_request(message, callback):
                     unsent.append(message)
-                _id += 1
 
             if unsent:
                 with self.lock:
@@ -553,12 +560,10 @@ class Network(util.DaemonThread):
     # FIXME: inline this function
     def process_request(self, request, callback):
         '''Returns true if the request was processed.'''
-        method = request['method']
-        params = request['params']
-        _id = request['id']
+        method, params = request
 
         if method.startswith('network.'):
-            out = {'id':_id}
+            out = {}
             try:
                 f = getattr(self, method[8:])
                 out['result'] = f(*params)
@@ -585,8 +590,8 @@ class Network(util.DaemonThread):
 
         if self.debug:
             self.print_error("-->", request)
-        self.unanswered_requests[_id] = request, callback
-        self.interface.queue_request(request)
+        message_id = self.queue_request(method, params)
+        self.unanswered_requests[message_id] = method, params, callback
         return True
 
     def connection_down(self, server):
@@ -603,8 +608,7 @@ class Network(util.DaemonThread):
     def new_interface(self, server, socket):
         self.add_recent_server(server)
         self.interfaces[server] = interface = Interface(server, socket)
-        interface.queue_request({'method': 'blockchain.headers.subscribe',
-                                 'params': []})
+        self.queue_request('blockchain.headers.subscribe', [], interface)
         if server == self.default_server:
             self.switch_to_interface(server)
         self.notify('interfaces')
@@ -625,9 +629,8 @@ class Network(util.DaemonThread):
             if interface.has_timed_out():
                 self.connection_down(interface.server)
             elif interface.ping_required():
-                version_req = {'method': 'server.version',
-                               'params': [ELECTRUM_VERSION, PROTOCOL_VERSION]}
-                interface.queue_request(version_req)
+                params = [ELECTRUM_VERSION, PROTOCOL_VERSION]
+                self.queue_request('server.version', params, interface)
 
         now = time.time()
         # nodes
@@ -653,8 +656,7 @@ class Network(util.DaemonThread):
 
     def request_chunk(self, interface, data, idx):
         interface.print_error("requesting chunk %d" % idx)
-        interface.queue_request({'method':'blockchain.block.get_chunk',
-                                 'params':[idx]})
+        self.queue_request('blockchain.block.get_chunk', [idx], interface)
         data['chunk_idx'] = idx
         data['req_time'] = time.time()
 
@@ -675,8 +677,7 @@ class Network(util.DaemonThread):
 
     def request_header(self, interface, data, height):
         interface.print_error("requesting header %d" % height)
-        interface.queue_request({'method':'blockchain.block.get_header',
-                                 'params':[height]})
+        self.queue_request('blockchain.block.get_header', [height], interface)
         data['header_height'] = height
         data['req_time'] = time.time()
         if not 'chain' in data:

scripts/estimate_fee

@@ -1,9 +1,5 @@
 #!/usr/bin/env python
 import util, json
 peers = util.get_peers()
-results = util.send_request(peers, {'method':'blockchain.estimatefee','params':[2]})
+results = util.send_request(peers, 'blockchain.estimatefee', [2])
 print json.dumps(results, indent=4)
-
-
-
-

scripts/peers

@@ -31,12 +31,9 @@ def analyze(results):
 
 
 peers = util.get_peers()
-results = util.send_request(peers, {'method':'blockchain.headers.subscribe','params':[]})
+results = util.send_request(peers, 'blockchain.headers.subscribe', [])
 
 errors = analyze(results).keys()
 
 for n,v in sorted(results.items(), key=lambda x:x[1].get('block_height')):
     print "%40s"%n, v.get('block_height'), v.get('utxo_root'), "error" if n in errors else "ok"
-
-
-

scripts/servers

@@ -10,7 +10,7 @@ set_verbosity(False)
 
 config = SimpleConfig()
 servers = filter_protocol(protocol = 't')
-results = util.send_request(servers, {'method':'blockchain.headers.subscribe', 'params':[]})
+results = util.send_request(servers, 'blockchain.headers.subscribe', [])
 
 d = defaultdict(int)
 

scripts/txradar

@@ -7,7 +7,7 @@ except:
     sys.exit(1)
 
 peers = util.get_peers()
-results = util.send_request(peers, {'method':'blockchain.transaction.get','params':[tx]})
+results = util.send_request(peers, 'blockchain.transaction.get', [tx])
 
 r1 = []
 r2 = []
@@ -17,4 +17,3 @@ for k, v in results.items():
 
 print "Received %d answers"%len(results)
 print "Propagation rate: %.1f percent" % (len(r1) *100./(len(r1)+ len(r2)))
-

scripts/util.py

@@ -16,13 +16,15 @@ def get_interfaces(servers, timeout=10):
             connecting[server] = Connection(server, socket_queue, config.path)
     interfaces = {}
     timeout = time.time() + timeout
-    while time.time() < timeout:
+    count = 0
+    while time.time() < timeout and count < len(servers):
         try:
-            server, socket = socket_queue.get(True, 1)
+            server, socket = socket_queue.get(True, 0.3)
         except Queue.Empty:
             continue
         if socket:
             interfaces[server] = Interface(server, socket)
+        count += 1
     return interfaces
 
 def wait_on_interfaces(interfaces, timeout=10):
@@ -37,7 +39,7 @@ def wait_on_interfaces(interfaces, timeout=10):
         for interface in wout:
             interface.send_requests()
         for interface in rout:
-            notifications, responses = interface.get_responses()
+            responses = interface.get_responses()
             if responses:
                 result[interface.server].extend(responses)
     return result
@@ -52,25 +54,23 @@ def get_peers():
         return []
     # 2. get list of peers
     interface = interfaces[server]
-    interface.queue_request({'id':0, 'method': 'server.peers.subscribe',
-                             'params': []})
-    responses = wait_on_interfaces(interfaces)
-    responses = responses.get(server)
+    interface.queue_request('server.peers.subscribe', [], 0)
+    responses = wait_on_interfaces(interfaces).get(server)
     if responses:
         response = responses[0][1]  # One response, (req, response) tuple
         peers = parse_servers(response.get('result'))
         peers = filter_protocol(peers,'s')
     return peers
 
-def send_request(peers, request):
+def send_request(peers, method, params):
     print "Contacting %d servers"%len(peers)
     interfaces = get_interfaces(peers)
     print "%d servers could be reached" % len(interfaces)
     for peer in peers:
         if not peer in interfaces:
             print "Connection failed:", peer
-    for i in interfaces.values():
-        i.queue_request(request)
+    for msg_id, i in enumerate(interfaces.values()):
+        i.queue_request(method, params, msg_id)
     responses = wait_on_interfaces(interfaces)
     for peer in interfaces:
         if not peer in responses: