Check for PID file prior to connecting to newly started web socket server

src/blenderbim/blenderbim/bim/data/webui/sioserver.py

@@ -119,15 +119,26 @@ async def gantt(request):
     return web.Response(text=html_content, content_type="text/html")
 
 
-async def open_web_browser(app):
-    webbrowser.open(f"http://127.0.0.1:{sio_port}/")
+async def on_startup(app):
+    pid_file = "running_pid.json"
+
+    if os.path.exists(pid_file):
+        with open(pid_file, "r") as f:
+            pids = json.load(f)
+    else:
+        pids = {}
+
+    pids[str(os.getpid())] = sio_port
+
+    with open(pid_file, "w") as f:
+        json.dump(pids, f, indent=4)
 
 
 app.router.add_get("/", index)
 app.router.add_get("/gantt", gantt)
 app.router.add_static("/jsgantt/", path="../gantt", name="jsgantt")
 app.router.add_static("/static/", path="./static", name="static")
-app.on_startup.append(open_web_browser)
+app.on_startup.append(on_startup)
 
 
 def main():

src/blenderbim/blenderbim/core/web.py

@@ -6,6 +6,10 @@ def connect_websocket_server(web, port):
     # check if port already has a server listening to it
     if web.is_port_available(port):
         web.start_websocket_server(port)
+        if web.has_started(port):
+            web.connect_websocket_server(port)
+            web.open_web_browser(port)
+        return
 
     web.connect_websocket_server(port)
 

src/blenderbim/blenderbim/tool/web.py

@@ -22,6 +22,7 @@ import blenderbim.core.tool
 import blenderbim.tool as tool
 import ifcopenshell.api.sequence
 from typing import Any, Dict, Optional
+import time
 import socket
 import sys
 import os
@@ -130,19 +131,6 @@ class Web(blenderbim.core.tool.Web):
             env=env,
         )
 
-        pid_file = os.path.join(webui_path, "running_pid.json")
-
-        if os.path.exists(pid_file):
-            with open(pid_file, "r") as f:
-                pids = json.load(f)
-        else:
-            pids = {}
-
-        pids[str(ws_process.pid)] = port
-
-        with open(pid_file, "w") as f:
-            json.dump(pids, f, indent=4)
-
         cls.set_is_running(True)
 
     @classmethod
@@ -230,6 +218,24 @@ class Web(blenderbim.core.tool.Web):
         cls.set_is_running(False)
         print("Websocket server terminated successfully")
 
+    @classmethod
+    def has_started(cls, port):
+        max_time = 5
+        start = time.time()
+        while True:
+            if time.time() - start > max_time:
+                return False
+            webui_path = os.path.join(bpy.context.scene.BIMProperties.data_dir, "webui")
+            pid_file = os.path.join(webui_path, "running_pid.json")
+            with open(pid_file, "r") as f:
+                try:
+                    data = json.load(f)
+                    if port in data.values():
+                        return True
+                except:
+                    pass
+            time.sleep(0.1)
+
     @classmethod
     def send_webui_data(
         cls,