getSession is undefined

[lunawen]

Hi, I'm new to GraphQL and today I'm using this library to learn subscription.

I followed the official doc and added graphql-ws to my project, with the example code.

However, I keep getting the "Unhandled GraphQL subscription error ReferenceError: getSession is not defined" error on my console.

Is there another library that I need to import? I googled but couldn't find it anywhere.. It would be good if the documentation can be clearer.

Thanks for your help!

[enisdenjo]

getSession is a placeholder example function that gets some session information meant to be implemented by you, it doesn't exist in this library.

[lunawen]

Ahhh, thanks for the clarification. Luna

…

On Apr 16, 2022, 22:19 +1000, Denis Badurina ***@***.***>, wrote: getSession is a placeholder example function meant to be implemented by you, it doesn't exist in this library. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[paymog]

ah, it looks like the cookies are included automatically serverside when using useServer under ctx.extra.request.rawHeaders. It seems the cookies need to be manually extracted from the raw headers though.

Something like this seems to be working for me:

      context: async (ctx, msg, args) => {
        // Returning an object will add that information to our
        // GraphQL context, which all of our resolvers have access to.
        const context = {};

        const rawHeaders = ctx.extra.request.rawHeaders;
        const cookieIndex = rawHeaders.indexOf('Cookie');
        const rawCookies = rawHeaders[cookieIndex + 1];
        const cookies = rawCookies.split(';');

        for (let i = 0; i < cookies.length; i++) {
          const cookie = cookies[i];
          const [key, value] = cookie.trim().split('=');
          if (key === 'app_login_token') {
            context.user = await getUserWithToken({ token: value });
            break;
          }
        }

        return context;
      },

[paymog]

ah, just saw your message while I was writing mine! Is it better to handle jwt auth over cookies in the various on... methods above or to set up the context like I've shown?

[enisdenjo]

I recommend, and personally always prefer, using onConnect callback for authenticating users and context for injecting into GraphQL's context. Roughly (warning, untested code):

import { parse as parseCookie } from 'cookie'; // yarn add cookie

...

useServer(
  {
    ...
    onConnect: async (ctx) => {
      const cookies = parseCookie(ctx.extra.request.headers.cookie);
      const authenticatedUser = await getUserWithToken({ token: cookies.app_login_token });
      if (!authenticatedUser) {
        return false; // will reject connection and close the WebSocket
      }

      // store the authenticated user in the context extra for easy reuse
      ctx.extra.user = authenticatedUser;
    },
    context: (ctx) => ({
      // inject the context's authenticated user into GraphQL context
      user: ctx.extra.user,
    }),
  },
  ...
);

P.S. you're better off using the headers.cookies over rawHeaders, NodeJS does the parsing from #352 (reply in thread) for you.

[paymog]

ah yup, using headers.cookies is much nicer!

Is there a particular reason you recommend and prefer using onConnect for auth? I have an intuition for why it's better but would like to know your reasons if you don't mind sharing.

[enisdenjo]

Is the connection callback called when the client requests the connection initialisation through the message ConnectionInit.

The message payload (connectionParams from the client) is present in the Context.connectionParams.

• Returning true or nothing from the callback will allow the client to connect.

• Returning false from the callback will terminate the socket by dispatching the close event 4403: Forbidden.

• Returning a Record from the callback will allow the client to connect and pass the returned value to the client through the optional payload field in the ConnectionAck message.

From onConnect documentation.

In essence, it's the best place because it is the "connection request" callback - the first thing that gets called when a client is establishing a connection.

[lunawen]

Sure, I'd love to! Just created a PR with some comments :) Luna

…

On 16 Apr 2022, 22:24 +1000, Denis Badurina ***@***.***>, wrote: If you have suggestions on how to make this clearer in the example, I'd love to hear it! PRs are always welcome. 😄 — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>