add analyzer proxy magic

artiq/coredevice/comm_analyzer.py

@@ -15,6 +15,7 @@ logger = logging.getLogger(__name__)
 
 
 DEFAULT_REF_PERIOD = 1e-9
+ANALYZER_MAGIC = b"ARTIQ Analyzer Proxy\n"
 
 
 class MessageType(Enum):
@@ -156,8 +157,9 @@ class AnalyzerProxyReceiver:
     async def connect(self, host, port):
         self.reader, self.writer = \
             await keepalive.async_open_connection(host, port)
-        magic = get_analyzer_magic()
         try:
+            line = await self.reader.readline()
+            assert line == ANALYZER_MAGIC
             self.receive_task = asyncio.create_task(self._receive_cr())
         except:
             if self.writer is not None:

artiq/frontend/aqctl_coreanalyzer_proxy.py

@@ -9,7 +9,7 @@ from sipyco.asyncio_tools import AsyncioServer, SignalHandler, atexit_register_c
 from sipyco.pc_rpc import Server
 from sipyco import common_args
 
-from artiq.coredevice.comm_analyzer import get_analyzer_dump
+from artiq.coredevice.comm_analyzer import get_analyzer_dump, ANALYZER_MAGIC
 
 
 logger = logging.getLogger(__name__)
@@ -24,6 +24,7 @@ class ProxyServer(AsyncioServer):
 
     async def _handle_connection_cr(self, reader, writer):
         try:
+            writer.write(ANALYZER_MAGIC)
             queue = asyncio.Queue(self._queue_limit)
             self._recipients.add(queue)
             try: