No route found for get /socket while trying to connect via websocket from client using Absinthe

Hi I am trying to send a subscription to server that is using absinthe graphql.
But I got an error in client side and server side.
in client side(flutter)

 Connecting to websocket: ws://
There was an error causing connection lost: WebSocketException: Connection to '' was not upgraded to websocket

and in my phoenix application

[info] GET /socket
[debug] ** (Phoenix.Router.NoRouteError) no route found for GET /socket (JaangWeb.Router)

So I don’t know what is causing this error.
in endpoint.ex

  socket "/socket", MyAppWeb.UserSocket,
    websocket: true,
    longpoll: false

in application.ex

def start(_type, _args) do
    children = [
      {Absinthe.Subscription, MyAppWeb.Endpoint}

    # See
    # for other strategies and supported options
    opts = [strategy: :one_for_one, name: MyApp.Supervisor]
    Supervisor.start_link(children, opts)

in user_socket.ex

  use Absinthe.Phoenix.Socket, schema: MyAppWeb.Schema

What else should I check?

Well, the actual route is /socket/websocket. If you set longpoll key to true, then /socket/longpoll will be available too.
Check your routes using

mix phx.routes | grep /socket

Perhaps, you’re looking for a library for working with Phoenix channels rather than with raw websockets. Anyway, which client library do you use?

1 Like

Hi Thanks for your reply.
Yes I can see /socket/websocket using mix phx.routes | grep /socket, so
I changed ws address to /socket/websocket.
Then I got a different error message says

[info] CONNECTED TO MyAppWeb.UserSocket in 35µs
  Transport: :websocket
  Serializer: Phoenix.Socket.V1.JSONSerializer
  Parameters: %{}
[error] Ranch listener MyAppWeb.Endpoint.HTTP had connection process started with :cowboy_clear:start_link/4 at #PID<0.926.0> exit with reason: {%Phoenix.Socket.InvalidMessageError{message: "missing key \"topic\""}, [{Phoenix.Socket.Message, :from_map!, 1, [file: 'lib/phoenix/socket/message.ex', line: 35]}, {Phoenix.Socket, :__in__, 2, [file: 'lib/phoenix/socket.ex', line: 466]}, {Phoenix.Endpoint.Cowboy2Handler, :websocket_handle, 2, [file: 'lib/phoenix/endpoint/cowboy2_handler.ex', line: 175]}, {:cowboy_websocket, :handler_call, 6, [file: '/home/taedori/elixir-project/my_app/deps/cowboy/src/cowboy_websocket.erl', line: 528]}, {:cowboy_http, :loop, 1, [file: '/home/taedori/elixir-project/my_app/deps/cowboy/src/cowboy_http.erl', line: 254]}, {:proc_lib, :init_p_do_apply, 3, [file: 'proc_lib.erl', line: 226]}]}

I am using graphql and graphql-flutter in the client.

When I used React for client project, I used to use packages like these

import * as AbsintheSocket from "@absinthe/socket";
import { createAbsintheSocketLink } from "@absinthe/socket-apollo-link";
import { Socket as PhoenixSocket } from "phoenix";

const socketLink = createAbsintheSocketLink(
  AbsintheSocket.create(new PhoenixSocket(WS_ENDPOINT))

To be honest, I don’t know what those packages actually doing :frowning:
I wonder if I need some kind of that packages in flutter project. something like this

Yes, definitely :slight_smile:

graphql-flutter is not compatible with the regular Absinthe.Phoenix wire protocol. Instead it uses the Apollo server protocol. If you wanted to use graphql-flutter on the client side you could try using on the Phoenix side to expose an Apollo server compatible websocket endpoint but I don’t know if it is up to date.

How can I use that packages in phoenix side?

Can you eleborate on this?

have you find how to fix you issue in flutter about “missing key “topic”” please

What are you trying to do? trying to use subscription from Absinthe?
If yes, I have no idea.
I am using websocket from flutter to phoenix server using this package

Thx for your answer
yes. Absinthe.
is your code with phoenix lib available to be share ?

what are you trying to do?

my issue is described here: Issue with Subscription with Phoenix · Issue #87 · archethic-foundation/archethic-wallet · GitHub