Write rules for Authorised() decorator of TypeGraphQL resolvers.

I wanted to make rules for using Authorised decorator in TypeGraphQL resolvers just like I used to make them for graphql-shield.

TypeGraphQL allows creating custom authCheckers to use authorization rules. However, it seems limited by the fact that it checks against roles and not rules that can be defined by the developer. Additionally, there seems to be no way to define conditionals such as AND or OR in the authChecker unless implemented by the user from scratch.

This library allows you to define rules for Authorised() decorator in TypeGraphQL resolvers.

Import the authChecker from typegraphql-authchecker. Then use the authChecker as TypeGraphQL's custom authChecker.

import authChecker from "typegraphql-authchecker";

// Use the authChecker as the custom authChecker for TypeGraphQL
buildSchema({
  resolvers,
  emitSchemaFile: true,
  authChecker: authChecker,
}).then((schema) => {});

Now, you can start creating rules and start using them!

For example, to check if user is authenticated:

import { Rule } from "typegraphql-authchecker";
import { Context } from "../context";

export const isAuthenticated: Rule<Context> = ({ context }) => {
  if (context.user) {
    return true;
  }
  return false;
};

Context in the Rule<Context> is the type of your GraphQL server context.

Use this rule for a resolver:

@Resolver()
export class UserResolver {
  @Authorized(isAuthenticated)
  @Query((returns) => User)
  async me(@Ctx() ctx: Context) {
    return ctx.user;
  }
}

Rules can be combined using AND, OR and NOT conditionals to perform complex authorization checks.

For example, by default, this will check if user is authenticated and if user is an admin.

@Authorized([isAuthenticated, isAdmin])

Another example, to check if user is admin or if user is a member, use OR conditional:

@Authorized([{OR: [isAdmin, isMember]}])

The conditionals can be nested, for example:

@Authorized([{ OR: [isAdmin, { AND: [isAuthenticated, isOwner]} ] }])

Thank you! Please open issues and pull requests on GitHub!