How to allow access-control-allow-origin with koa?

by cortez.connelly , in category: Javascript , 6 months ago

How to allow access-control-allow-origin with koa?

Facebook Twitter LinkedIn Telegram Whatsapp

1 answer

Member

by orpha , 6 months ago

@cortez.connelly 

To allow access-control-allow-origin with Koa, you can use the koa-cors middleware. Here's how you can do it:

  1. Install the koa-cors package:
1
npm install koa-cors


  1. Import koa-cors in your Koa application:
1
2
3
4
5
6
7
const Koa = require('koa');
const cors = require('koa-cors');

const app = new Koa();

// Use the cors middleware
app.use(cors());


  1. Customize the CORS settings if needed:


You can pass options to the cors middleware to customize the CORS settings. For example, to allow requests from a specific origin, you can set the origin option:

1
2
3
app.use(cors({
  origin: 'http://example.com',
}));


  1. Handle preflight requests:


If your clients are making requests that require preflight requests (OPTIONS requests), you can use the koa-router middleware to handle these requests:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
const Router = require('koa-router');
const router = new Router();

router.options('/*', (ctx) => {
  // Handle preflight requests
  ctx.status = 204;
});

app.use(router.routes());
app.use(router.allowedMethods());


By following these steps, you can easily allow access-control-allow-origin with Koa and customize the CORS settings as needed.