API Service

A tiny frontend library to help create a "service wrapper" over backend APIs. Helps track API tokens and boilerplate for API responses.

You write an 'AuthManager' class to keep track of the current logged in JWT token.

import { AuthManager, localStorage } from '@lcdev/api-service';

interface JWT { ... } // whatever your JWT contains

export class MyAuthManager extends AuthManager<JWT> {
  static async create() {
    const manager = new MyAuthManager(
      localStorage(), // where to store the token
      {
        // this is the key that's used in the above functions
        tokenKey: 'token-key',

        // when to automatically call refresh, in keepAlive
        refreshTokenWithinSeconds: 60 * 30,
      },
      {
        async refreshToken(currentToken) {
          // call an API, return back the jwt string
        },
        // optional - any errors trigger this callback
        error(err) { ... }
        // optional - any 401 errors trigger this callback
        unauthorized() { ... }
        // optional - when token has expired, this callback is triggered
        expiry() { ... }
      },
    );

    return manager.waitUntilReady();
  }
}

Your API calling service would look like this.

import { api } from '@lcdev/fetch';
import { ApiResponse, unwrapApiResponse } from '@lcdev/api-service';

export const createCoreApi = (baseURL: string, auth: MyAuthManager) => {
  const coreApi = api(baseURL)
    .withBearerToken(auth)
    // optional - logic to automatically keepAlive after every API request
    .onResponse(res => {
      if (!/\/auth\//.exec(res.url)) {
        auth.keepAlive().catch(() => {});
      }
    });

  // this is an object with calls to all endpoints of your API
  return {
    async login(username: string, password: string) {
      type Response = ApiResponse<ApiData.Token>;

      const response = await coreApi
        .post('/api/auth/login')
        .withBody({ username, password })
        .json<Response>();

      const { data } = unwrapApiResponse(response);

      return data;
    },
  } as const;
};