gql-auth-directives

---

Summary

gql-auth-directives is a set of schema directives that allows a granular approach to role-based access control with GraphQL.

Features

• Directives for roles, permissions and authentication
• Allows access control for queries, mutations
• Allows access control for input types
• Provided with default handlers using JWTs

Getting Started

Prerequisites

This package requires the user to use a server that supports Apollo schema directives.

Installing

Use npm

$ npm install --save gql-auth-directives

or yarn

$ yarn add gql-auth-directives

to install the package.

Available directives

• @hasRole(roles: ["ADMIN", "USER"])

  A user with either an admin or user role will be authorized

• @hasPermission(permissions: ["CREATE_USERS"])
• @isAuthenticated

Setup

Default handlers

To use the default handlers, the environment variable JWT_SECRET must be set. The variable will be used for verifying authorization headers and grab roles/permissions arrays in the token's payload.

We need to generate the auth directives and add it to the server configuration like so:

import { createAuthDirectives } from "gql-auth-directives";

const authDirectives = createAuthDirectives();

const server = new ApolloServer({
  typeDefs,
  resolvers,
  schemaDirectives: { ...authDirectives },
  context(ctx) {
    return { ...ctx }; // ⚠ Make sure to always pass the ctx from the server's context function
  },
});

Override handlers

The library also allows using custom functions for the provided directives.

You could override the hasPermission handler like so:

import { createAuthDirectives } from "gql-auth-directives";

const authDirectives = createAuthDirectives({
  hasPermissionHandler: (ctx, permissions) => {
    const user = getUser(ctx);
    // Do something with the user and throw an error if the user's permissions doesn't match the permissions passed
  },
});

const server = new ApolloServer({
  typeDefs,
  resolvers,
  schemaDirectives: { ...authDirectives },
  context(ctx) {
    return { ...ctx };
  },
});

Schema declarations

We also need to add the directives declarations at the top of our GraphQL schema like so:

directive @isAuthenticated on FIELD | FIELD_DEFINITION | INPUT_FIELD_DEFINITION
directive @hasPermission(permissions: [String!]!) on FIELD | FIELD_DEFINITION | INPUT_FIELD_DEFINITION
directive @hasRole(roles: [String!]!) on FIELD | FIELD_DEFINITION | INPUT_FIELD_DEFINITION

[...]

If you use something like makeExecutableSchema from graphql-tools that allows schema stitching you can also add the directives declarations like so:

import { createAuthDirectives, authTypeDefs } from "gql-auth-directives";
import { makeExecutableSchema } from "graphql-tools";

const authDirectives = createAuthDirectives();

const schema = makeExecutableSchema({
  resolvers,
  typeDefs: [authTypeDefs, typeDefs],
  schemaDirectives: { ...authDirectives },
});

const server = new ApolloServer({
  schema,
  context(ctx) {
    return { ...ctx };
  },
});

Usage

We can now use our directives inside our GraphQL schema:

input CreatePostInput {
  name: String!
  description: String!
  published: Boolean @hasPermission(permissions: ["PUBLISH_POST"])
}

type Mutation {
  createPost(data: CreatePostInput!): Post! @hasRole(roles: ["AUTHOR"])
}

type Query {
  me: User! @isAuthenticated
}

ℹ Notice that you can also use the directives for inputs. If an unauthorized user tries to fill the published field it will throw an error and never reach the resolver.

License

MIT