fix(api): raise Socket.IO max_http_buffer_size for large workflows (#41347)

api/.env.example

@@ -222,6 +222,7 @@ SUPABASE_URL=your-server-url
 # CORS configuration
 WEB_API_CORS_ALLOW_ORIGINS=http://localhost:3000,*
 CONSOLE_CORS_ALLOW_ORIGINS=http://localhost:3000,*
+WEBSOCKET_MAX_HTTP_BUFFER_SIZE=10485760
 # When the frontend and backend run on different subdomains, set COOKIE_DOMAIN to the site’s top-level domain (e.g., `example.com`). Leading dots are optional.
 COOKIE_DOMAIN=
 

api/configs/feature/__init__.py

@@ -593,6 +593,16 @@ class HttpConfig(BaseSettings):
     def CONSOLE_CORS_ALLOW_ORIGINS(self) -> list[str]:
         return self.inner_CONSOLE_CORS_ALLOW_ORIGINS.split(",")
 
+    WEBSOCKET_MAX_HTTP_BUFFER_SIZE: PositiveInt = Field(
+        description=(
+            "Maximum Socket.IO / Engine.IO HTTP buffer size in bytes. "
+            "Large workflow collaboration payloads (sync_request graph snapshots) "
+            "exceed the Engine.IO default of 1 MiB and get rejected, which "
+            "disconnects the editor WebSocket. Default is 10 MiB."
+        ),
+        default=10 * 1024 * 1024,
+    )
+
     inner_WEB_API_CORS_ALLOW_ORIGINS: str = Field(
         description="",
         validation_alias=AliasChoices("WEB_API_CORS_ALLOW_ORIGINS"),

api/extensions/ext_socketio.py

@@ -73,5 +73,6 @@ sio = cast(
         async_mode="gevent",
         client_manager=create_socketio_client_manager(),
         cors_allowed_origins=dify_config.CONSOLE_CORS_ALLOW_ORIGINS,
+        max_http_buffer_size=dify_config.WEBSOCKET_MAX_HTTP_BUFFER_SIZE,
     ),
 )

api/tests/integration_tests/.env.example

@@ -55,6 +55,7 @@ OPENDAL_FS_ROOT=storage
 # CORS configuration
 WEB_API_CORS_ALLOW_ORIGINS=http://127.0.0.1:3000,*
 CONSOLE_CORS_ALLOW_ORIGINS=http://127.0.0.1:3000,*
+WEBSOCKET_MAX_HTTP_BUFFER_SIZE=10485760
 
 # Vector database configuration
 # support: weaviate, qdrant, milvus, myscale, relyt, pgvecto_rs, pgvector, pgvector, chroma, opensearch, tidb_vector, couchbase, vikingdb, upstash, lindorm, oceanbase, iris

api/tests/unit_tests/extensions/test_ext_socketio.py

@@ -3,6 +3,7 @@ import ssl
 import pytest
 import socketio
 
+from configs import dify_config
 from extensions import ext_socketio
 
 
@@ -44,3 +45,7 @@ def test_build_redis_options_omits_socket_timeout(monkeypatch: pytest.MonkeyPatc
 
     assert "socket_timeout" not in options
     assert "socket_connect_timeout" in options
+
+
+def test_socketio_server_uses_configured_max_http_buffer_size() -> None:
+    assert ext_socketio.sio.eio.max_http_buffer_size == dify_config.WEBSOCKET_MAX_HTTP_BUFFER_SIZE

docker/envs/core-services/shared.env.example

@@ -319,6 +319,7 @@ CELERY_SENTINEL_MASTER_NAME=
 CELERY_SENTINEL_SOCKET_TIMEOUT=0.1
 WEB_API_CORS_ALLOW_ORIGINS=*
 CONSOLE_CORS_ALLOW_ORIGINS=*
+WEBSOCKET_MAX_HTTP_BUFFER_SIZE=10485760
 COOKIE_DOMAIN=
 OPENDAL_SCHEME=fs
 OPENDAL_FS_ROOT=storage