just-the-cors

Tiny middleware to add cors support when using zeit's micro

Install

$ npm i just-the-cors

Example

const { send } = require("micro");
const { router, get } = require("microrouter");
const cors = require("just-the-cors");

const getWithCors = (path, handler) => get(path, cors(handler));

const hello = cors((req, res) => send(res, 200, { message: "Hello 1!" }));
const hello2 = (req, res) => {
	cors(req, res);
	return send(res, 200, { message: "Hello 2!" });
};
const hello3 = (req, res) => send(res, 200, { message: "Hello 3!" });
const hello4 = (req, res) => send(res, 200, { message: "Hello 4!" });

module.exports = router(
	get("/hello/1", hello),
	get("/hello/2", hello2),
	get("/hello/3", cors(hello3)),
	options("/hello/4", cors(hello4, { autoHandleOptions: false })),
	getWithCors("/*", (req, res) => send(res, 200, { message: "Hello in general!" })),
);

Note

If you don't supply the res object as a second argument, cors does nothing!

const { router, get } = require("microrouter");
const cors = require("just-the-cors");

const hello1 = (req) => {
	cors(req); // Does nothing!
	return "Hello 1";
};

const hello2 = (req, res) => {
	cors(req, res);
	return "Hello 2";
};

module.exports = router(
	get("/hello1", hello1), // "Access-Control-Allow-Origin": ❌
	get("/hello2", hello2) // "Access-Control-Allow-Origin": ✅
);