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jsonnode.jsrestexpressjsonp

How to support both json and jsonp responses in node.js + Express?

I'm have a REST API service, written on Node.js + Express, which currently support responses in JSON format.

Now, I need to add support for JSONP responses too, so everyone may get it by adding alt=JSONP to the request string.

So, my question is, which is the best way to do so?

Possible, there is an pattern, or living example?

Thanks!

Solution

  • The officially supported method is as follows --

    First, set your JSONP callback parameter name:

    app.set('jsonp callback name', 'callback');

    Then, change all instances of res.json or res.send to res.jsonp. For example, res.jsonp(500, { error: 'message' })

    If the callback parameter is supplied in a request, the response will be wrapped as JSONP using the supplied function name, but if it isn't, it'll just return JSON.

    Afterwards, this returns JSONP: GET /myapi/v1/users?callback=responseCallback

    This does not: GET /myapi/v1/users

    Reference http://expressjs.com/4x/api.html#res.jsonp