Added a zeroconf server to the LabThings server

Author: Joel Collins

labthings/server/wsgi/gevent.py

@@ -1,24 +1,58 @@
 from geventwebsocket.handler import WebSocketHandler
 import gevent
+import socket
 import logging
 import sys
 import os
 import signal
 from werkzeug.debug import DebuggedApplication
 
+from zeroconf import IPVersion, ServiceInfo, Zeroconf, get_all_addresses
+
+from ..find import current_labthing
+
 
 class Server:
     def __init__(self, app):
         self.app = app
+        # Find LabThing attached to app
+        self.labthing = current_labthing(app)
 
-    def run(self, host="0.0.0.0", port=5000, log=None, debug=False, stop_timeout=1):
+    def run(
+        self,
+        host="0.0.0.0",
+        port=5000,
+        log=None,
+        debug=False,
+        stop_timeout=1,
+        zeroconf=True,
+    ):
         # Type checks
         port = int(port)
         host = str(host)
 
         # Unmodified version of app
         app_to_run = self.app
 
+        # Handle zeroconf
+        zeroconf_server = None
+        if zeroconf and self.labthing:
+            service_info = ServiceInfo(
+                "_labthings._tcp.local.",
+                f"{self.labthing.title}._labthings._tcp.local.",
+                port=port,
+                properties={"path": self.labthing.url_prefix},
+                addresses=set(
+                    [
+                        socket.inet_aton(i)
+                        for i in get_all_addresses()
+                        if i not in ("127.0.0.1", "0.0.0.0")
+                    ]
+                ),
+            )
+            zeroconf_server = Zeroconf(ip_version=IPVersion.V4Only)
+            zeroconf_server.register_service(service_info)
+
         # Handle logging
         if not log:
             log = logging.getLogger()
@@ -27,7 +61,9 @@ def run(self, host="0.0.0.0", port=5000, log=None, debug=False, stop_timeout=1):
         if debug:
             log.setLevel(logging.DEBUG)
             app_to_run = DebuggedApplication(self.app)
+            logging.getLogger("zeroconf").setLevel(logging.DEBUG)
 
+        # Slightly more useful logger output
         friendlyhost = "localhost" if host == "0.0.0.0" else host
         logging.info("Starting LabThings WSGI Server")
         logging.info(f"Debug mode: {debug}")
@@ -39,6 +75,11 @@ def run(self, host="0.0.0.0", port=5000, log=None, debug=False, stop_timeout=1):
         )
 
         def stop():
+            # Unregister zeroconf service
+            if zeroconf_server:
+                zeroconf_server.unregister_service(service_info)
+                zeroconf_server.close()
+            # Stop WSGI server with timeout
             wsgi_server.stop(timeout=stop_timeout)
 
         # Serve