Add support for ipv6

Dockerfile

@@ -10,7 +10,7 @@ ENV PYTHONUNBUFFERED=1
 ENV FLASK_ENV=production
 ENV LOG_LEVEL=info
 
-CMD ["sh", "-c", "gunicorn -b 0.0.0.0:4499 turnify:app \
-    --log-level $(echo $LOG_LEVEL | tr '[:upper:]' '[:lower:]') \
-    --access-logfile ${GUNICORN_ACCESS_LOG:-'-'} \
-    --error-logfile ${GUNICORN_ERROR_LOG:-'-'}"]
+COPY entrypoint.sh /app/entrypoint.sh
+RUN chmod +x /app/entrypoint.sh
+
+CMD ["/app/entrypoint.sh"]

app/turnify.py

@@ -23,7 +23,7 @@
 @app.before_request
 def log_request():
     app.logger.debug(f"Received {request.method} request to {request.path} from {request.remote_addr}")
-    
+
 @app.route('/<path:subpath>/voip/turnServer', methods=['GET'])
 def proxy_request(subpath):
     app.logger.debug(f"Handling {request.method} request for {request.path}")
@@ -126,7 +126,7 @@ def generate():
             status=response.status_code,
             headers={key: value for key, value in response.headers.items() if key.lower() != 'transfer-encoding'}
         )
-    
+
     except requests.exceptions.RequestException as e:
         app.logger.error(f"{ip_addr} -- Error forwarding request to Synapse: {e}")
         return jsonify({"error": "Failed to connect to Synapse"}), 502

entrypoint.sh

@@ -0,0 +1,37 @@
+#!/bin/sh
+
+python3 - <<'EOF'
+import socket, sys
+try:
+    s = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
+    s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+    s.bind(("::", 4499))
+    s.listen(1)
+
+    test = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    try:
+        test.connect(("127.0.0.1", 4499))
+        sys.exit(0)
+    except Exception:
+        sys.exit(1)
+    finally:
+        test.close()
+except Exception:
+    sys.exit(1)
+finally:
+    s.close()
+EOF
+
+if [ $? -eq 0 ]; then
+    echo "Use IPv4-mapped IPv6"
+    exec gunicorn -w 4 -b [::]:4499 turnify:app \
+        --log-level "$(echo $LOG_LEVEL | tr '[:upper:]' '[:lower:]')" \
+        --access-logfile "${GUNICORN_ACCESS_LOG:--}" \
+        --error-logfile "${GUNICORN_ERROR_LOG:--}"
+else
+    echo "Use manual IPv4 and IPv6 binding"
+    exec gunicorn -w 4 -b 0.0.0.0:4499 -b [::]:4499 turnify:app \
+        --log-level "$(echo $LOG_LEVEL | tr '[:upper:]' '[:lower:]')" \
+        --access-logfile "${GUNICORN_ACCESS_LOG:--}" \
+        --error-logfile "${GUNICORN_ERROR_LOG:--}"
+fi