Enable servers

server/block_processor.py

@@ -126,17 +126,18 @@ class BlockProcessor(LoggedClass):
     Coordinate backing up in case of chain reorganisations.
     '''
 
-    def __init__(self, env, daemon):
+    def __init__(self, env, daemon, on_catchup=None):
         super().__init__()
 
         self.daemon = daemon
+        self.on_catchup = on_catchup
 
         # Meta
         self.utxo_MB = env.utxo_MB
         self.hist_MB = env.hist_MB
         self.next_cache_check = 0
         self.coin = env.coin
-        self.caught_up = False
+        self.have_caught_up = False
         self.reorg_limit = env.reorg_limit
 
         # Chain state (initialize to genesis in case of new DB)
@@ -192,6 +193,17 @@ class BlockProcessor(LoggedClass):
         else:
             return [self.start(), self.prefetcher.start()]
 
+    async def caught_up(self):
+        '''Call when we catch up to the daemon's height.'''
+        # Flush everything when in caught-up state as queries
+        # are performed on DB and not in-memory.
+        self.flush(True)
+        if not self.have_caught_up:
+            self.have_caught_up = True
+            self.logger.info('caught up to height {:,d}'.format(self.height))
+            if self.on_catchup:
+                await self.on_catchup()
+
     async def start(self):
         '''External entry point for block processing.
 
@@ -199,32 +211,26 @@ class BlockProcessor(LoggedClass):
         shutdown.
         '''
         try:
-            await self.advance_blocks()
+            # If we're caught up so the start servers immediately
+            if self.height == await self.daemon.height():
+                await self.caught_up()
+            await self.wait_for_blocks()
         finally:
             self.flush(True)
 
-    async def advance_blocks(self):
+    async def wait_for_blocks(self):
         '''Loop forever processing blocks in the forward direction.'''
         while True:
             blocks = await self.prefetcher.get_blocks()
             for block in blocks:
                 if not self.advance_block(block):
                     await self.handle_chain_reorg()
-                    self.caught_up = False
+                    self.have_caught_up = False
                     break
                 await asyncio.sleep(0)   # Yield
 
-            if self.height != self.daemon.cached_height():
-                continue
-
-            if not self.caught_up:
-                self.caught_up = True
-                self.logger.info('caught up to height {:,d}'
-                                 .format(self.height))
-
-            # Flush everything when in caught-up state as queries
-            # are performed on DB not in-memory
-            self.flush(True)
+            if self.height == self.daemon.cached_height():
+                await self.caught_up()
 
     async def force_chain_reorg(self, to_genesis):
         try:
@@ -360,7 +366,7 @@ class BlockProcessor(LoggedClass):
 
     def flush_state(self, batch):
         '''Flush chain state to the batch.'''
-        if self.caught_up:
+        if self.have_caught_up:
             self.first_sync = False
         now = time.time()
         self.wall_time += now - self.last_flush

server/controller.py

@@ -13,6 +13,7 @@ client-serving data such as histories.
 
 import asyncio
 import signal
+import ssl
 import traceback
 from functools import partial
 
@@ -35,51 +36,62 @@ class Controller(LoggedClass):
         self.loop = loop
         self.env = env
         self.daemon = Daemon(env.daemon_url)
-        self.block_processor = BlockProcessor(env, self.daemon)
+        self.block_processor = BlockProcessor(env, self.daemon,
+                                              on_catchup=self.start_servers)
         self.servers = []
         self.sessions = set()
         self.addresses = {}
-        self.jobs = set()
+        self.jobs = asyncio.Queue()
         self.peers = {}
 
     def start(self):
-        '''Prime the event loop with asynchronous servers and jobs.'''
-        env = self.env
-        loop = self.loop
-
+        '''Prime the event loop with asynchronous jobs.'''
         coros = self.block_processor.coros()
-
-        if False:
-            self.start_servers()
-            coros.append(self.reap_jobs())
+        coros.append(self.run_jobs())
 
         for coro in coros:
             asyncio.ensure_future(coro)
 
         # Signal handlers
         for signame in ('SIGINT', 'SIGTERM'):
-            loop.add_signal_handler(getattr(signal, signame),
-                                    partial(self.on_signal, signame))
+            self.loop.add_signal_handler(getattr(signal, signame),
+                                         partial(self.on_signal, signame))
+
+    async def start_servers(self):
+        '''Start listening on RPC, TCP and SSL ports.
+
+        Does not start a server if the port wasn't specified.  Does
+        nothing if servers are already running.
+        '''
+        if self.servers:
+            return
+
+        env = self.env
+        loop = self.loop
 
-    def start_servers(self):
         protocol = partial(LocalRPC, self)
         if env.rpc_port is not None:
             host = 'localhost'
             rpc_server = loop.create_server(protocol, host, env.rpc_port)
-            self.servers.append(loop.run_until_complete(rpc_server))
+            self.servers.append(await rpc_server)
             self.logger.info('RPC server listening on {}:{:d}'
                              .format(host, env.rpc_port))
 
         protocol = partial(ElectrumX, self, self.daemon, env)
         if env.tcp_port is not None:
             tcp_server = loop.create_server(protocol, env.host, env.tcp_port)
-            self.servers.append(loop.run_until_complete(tcp_server))
+            self.servers.append(await tcp_server)
             self.logger.info('TCP server listening on {}:{:d}'
                              .format(env.host, env.tcp_port))
 
         if env.ssl_port is not None:
-            ssl_server = loop.create_server(protocol, env.host, env.ssl_port)
-            self.servers.append(loop.run_until_complete(ssl_server))
+            # FIXME: update if we want to require Python >= 3.5.3
+            ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLSv1_2)
+            ssl_context.load_cert_chain(env.ssl_certfile,
+                                        keyfile=env.ssl_keyfile)
+            ssl_server = loop.create_server(protocol, env.host, env.ssl_port,
+                                            ssl=ssl_context)
+            self.servers.append(await ssl_server)
             self.logger.info('SSL server listening on {}:{:d}'
                              .format(env.host, env.ssl_port))
 
@@ -96,30 +108,28 @@ class Controller(LoggedClass):
             task.cancel()
 
     def add_session(self, session):
+        '''Add a session representing one incoming connection.'''
         self.sessions.add(session)
 
     def remove_session(self, session):
+        '''Remove a session.'''
         self.sessions.remove(session)
 
     def add_job(self, coro):
         '''Queue a job for asynchronous processing.'''
-        self.jobs.add(asyncio.ensure_future(coro))
+        self.jobs.put_nowait(coro)
 
-    async def reap_jobs(self):
+    async def run_jobs(self):
+        '''Asynchronously run through the job queue.'''
         while True:
-            jobs = set()
-            for job in self.jobs:
-                if job.done():
-                    try:
-                        job.result()
-                    except Exception as e:
-                        traceback.print_exc()
-                else:
-                    jobs.add(job)
-            self.logger.info('reaped {:d} jobs, {:d} jobs pending'
-                             .format(len(self.jobs) - len(jobs), len(jobs)))
-            self.jobs = jobs
-            await asyncio.sleep(5)
+            job = await self.jobs.get()
+            try:
+                await job
+            except asyncio.CancelledError:
+                raise
+            except Exception:
+                # Getting here should probably be considered a bug and fixed
+                traceback.print_exc()
 
     def address_status(self, hash168):
         '''Returns status as 32 bytes.'''

server/env.py

@@ -34,6 +34,9 @@ class Env(LoggedClass):
         # Server stuff
         self.tcp_port = self.integer('TCP_PORT', None)
         self.ssl_port = self.integer('SSL_PORT', None)
+        if self.ssl_port:
+            self.ssl_certfile = self.required('SSL_CERTFILE')
+            self.ssl_keyfile = self.required('SSL_KEYFILE')
         self.rpc_port = self.integer('RPC_PORT', 8000)
         self.max_subscriptions = self.integer('MAX_SUBSCRIPTIONS', 10000)
         self.banner_file = self.default('BANNER_FILE', None)

server/protocol.py

@@ -24,6 +24,14 @@ class Error(Exception):
 
 
 class JSONRPC(asyncio.Protocol, LoggedClass):
+    '''Base class that manages a JSONRPC connection.
+
+    When a request comes in for an RPC method M, then a member
+    function handle_M is called with the request params array, except
+    that periods in M are replaced with underscores.  So a RPC call
+    for method 'blockchain.estimatefee' will be passed to
+    handle_blockchain_estimatefee.
+    '''
 
     def __init__(self, controller):
         super().__init__()
@@ -31,39 +39,41 @@ class JSONRPC(asyncio.Protocol, LoggedClass):
         self.parts = []
 
     def connection_made(self, transport):
+        '''Handle an incoming client connection.'''
         self.transport = transport
-        peername = transport.get_extra_info('peername')
-        self.logger.info('connection from {}'.format(peername))
+        self.peername = transport.get_extra_info('peername')
+        self.logger.info('connection from {}'.format(self.peername))
         self.controller.add_session(self)
 
     def connection_lost(self, exc):
-        self.logger.info('disconnected')
+        '''Handle client disconnection.'''
+        self.logger.info('disconnected: {}'.format(self.peername))
         self.controller.remove_session(self)
 
     def data_received(self, data):
+        '''Handle incoming data (synchronously).
+
+        Requests end in newline characters.  Pass complete requests to
+        decode_message for handling.
+        '''
         while True:
             npos = data.find(ord('\n'))
             if npos == -1:
+                self.parts.append(data)
                 break
             tail, data = data[:npos], data[npos + 1:]
-            parts = self.parts
-            self.parts = []
+            parts, self.parts = self.parts, []
             parts.append(tail)
             self.decode_message(b''.join(parts))
 
-        if data:
-            self.parts.append(data)
-
     def decode_message(self, message):
-        '''Message is a binary message.'''
+        '''Decode a binary message and queue it for asynchronous handling.'''
         try:
             message = json.loads(message.decode())
         except Exception as e:
-            self.logger.info('caught exception decoding message'.format(e))
-            return
-
-        job = self.request_handler(message)
-        self.controller.add_job(job)
+            self.logger.info('error decoding JSON message'.format(e))
+        else:
+            self.controller.add_job(self.request_handler(message))
 
     async def request_handler(self, request):
         '''Called asynchronously.'''