How to use fastify-cors to enable just one api to cross domain?

Question

I want to let [POST] localhost/product just this API to cross-domain.

I don't know how to do it

fastify.register(require('fastify-cors'), {
  origin:'*',
  methods:['POST'],
  
})

this is my API:

{
      method: 'POST',
      url: '/product',
      handler: productsController.addProduct,
},

luawtf · Accepted Answer · 2021-01-04T09:16:15.477

12

In this case, an external dependency is not required. Instead, set the CORS headers manually in productsController.addProduct.

Example of manual CORS header manipulation:

function addProduct(request, reply) {
  reply.header("Access-Control-Allow-Origin", "*");
  reply.header("Access-Control-Allow-Methods", "POST");
  // ... more code here ...
}

If you still want to use fastify-cors, try something like this:

fastify.register((fastify, options, done) => {
  fastify.register(require("fastify-cors"), {
    origin: "*",
    methods: ["POST"]
  });
  fastify.route({
    method: "POST",
    url: "/product",
    handler: productsController.addProduct
  });
  done();
});

edited Jan 04 '21 at 09:16

answered Jan 04 '21 at 03:22

luawtf

576
8
21

1

thanks for your reply. this must be a great solution for solve my problem.But could you tell me how to do it by fastify-cors. – radiorz Jan 04 '21 at 03:49
Got it! Updated my answer. – luawtf Jan 04 '21 at 04:56
1

OMG,it return error: Error: plugin must be a function or a promise – radiorz Jan 04 '21 at 07:22
1

Oops! I've changed the answer again so that Fastify's plugin system is correctly used, this should work (atleast it did in my environment). – luawtf Jan 04 '21 at 09:17
3

The first one didn't work the second one does – Bitwise DEVS Jun 26 '21 at 09:14

Seph Reed · Answer 2 · 2022-10-19T20:08:01.137

This is currently the top hit for "fastify cors" on multiple search engines. If -- like me -- you saw that an entire npm package exists for it but would rather just set a few headers on your own, here is how:

const server = Fastify({});
server.addHook('preHandler', (req, res, done) => {

  // example logic for conditionally adding headers
  const allowedPaths = ["/some", "/list", "/of", "/paths"];
  if (allowedPaths.includes(req.routerPath)) {
    res.header("Access-Control-Allow-Origin", "*");
    res.header("Access-Control-Allow-Methods", "POST");
    res.header("Access-Control-Allow-Headers",  "*");
  }

  const isPreflight = /options/i.test(req.method);
  if (isPreflight) {
    return res.send();
  }
      
  done();
})

How to use fastify-cors to enable just one api to cross domain?

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