Authorization in your remote schema server

Introduction

This page gives an overview of how to manage authorization for your remote schemas.

Authorization basics

Hasura will forward the resolved x-hasura-* values as headers to your remote schema. You can use this information to apply authorization rules in your server. You don’t have to redo authentication in your remote schema server. Native fine grained access control for remote schemas will be released soon.

You can also configure Hasura to have (as shown here):

  1. static header values that are sent to the remote server
  2. forward all headers from the client (like Authorization, Cookie headers etc.)
  3. Fine grained access control

In case there are multiple headers with same name, the order of precedence is: configuration headers > resolved user (x-hasura-*) variables > client headers.

So for example, if the client sends an Authorization header, and the configuration also has an Authorization header, the configuration header value will selected.

Note

The headers from the client behave similarly to the authorization system. If x-hasura-admin-secret is sent, then all x-hasura-* values from the client are respected, otherwise they are ignored.

Bypassing Hasura’s authorization system for remote schema requests

It might be necessary sometimes to bypass Hasura’s authorization system (calling the configured webhook, or validating the JWT), for requests that are for a remote GraphQL server.

For example, you have a remote GraphQL server which does authentication, i.e. signup and login, and you have added it as a remote schema. In this case, you would not want to perform Hasura’s authorization when the user is making a login/signup request.

There is no first-class option to currently do this via any configuration in Hasura. However a similar solution can be achieved by the following workarounds:

Bypassing webhook authorization

If you have a webhook authorization setup, in the normal scenario, your authorization webhook would return 200 on success and 401 if it is either unable to authorize the current request or if the authorization information is absent (like cookie, authorization header etc.)

To bypass the webhook auth:

  • the webhook should respond with 200 and x-hasura-role: anonymous instead of a 401 when the authorization information is absent or if it fails to resolve the authorization information.
  • when adding the remote schema, check the Forward all headers from client option so that the remote server will get the relevant cookie/header (from the client) and the role anonymous.

Bypassing JWT authorization

If you have a JWT authorization setup, to bypass the JWT auth:

  • your authentication server should generate a static JWT token for anonymous i.e. unauthenticated users.
  • when adding the remote schema, check the Forward all headers from client option so that the remote server will get the JWT (from the client).

For example, the generated JWT can be:

{
  "sub": "0000000000",
  "iat": 1516239022,
  "role": "anonymous",
  "https://hasura.io/jwt/claims": {
    "x-hasura-allowed-roles": ["anonymous"],
    "x-hasura-default-role": "anonymous"
  }
}

Hasura will get this JWT and successfully validate it. When your remote server receives this JWT, it should specifically validate the JWT and, for example, check for the role key in the JWT. If it is set to anonymous, then it should consider the request as unauthenticated.