context.ts

import { GraphQLError } from "graphql";
import { authorize } from "./services/Cerbos.service";
import { Users } from "./data/users.data";
import { Principal } from "@cerbos/core";
import { StandaloneServerContextFunctionArgument } from "@apollo/server/dist/esm/standalone";
import { ContextFunction } from "@apollo/server";

export interface Context {
  principal: Principal;
  authorizer: ReturnType<typeof authorize>;
}

export const createContext: ContextFunction<
  [StandaloneServerContextFunctionArgument],
  Context
> = async ({ req }) => {
  const token = (req.headers.token as string) || "";
  const principal = Users[token];
  if (!token || !principal) {
    throw new GraphQLError("User is not authenticated", {
      extensions: {
        code: "UNAUTHENTICATED",
        http: { status: 401 },
      },
    });
  }

  return {
    principal,
    authorizer: authorize(principal),
  };
};