How can I buffer a http response using the request

问题:

I would to convert a incoming http response which is a stream and store the data in a variable. I don't much about node streams and I am struggling to do this properly.

var request = require('request');

request('http://google.com/doodle.png', function (error, response, body) {

     // buffer the stream response to and a string variable.   
})

UPDATE

This my full code. My goal is to get the image with request and store it in mongodb. But the image is always corrupted. I thought because request response was a stream, the image was only been partially saved and hence the corruption.

request('http://google.com/doodle.png', function (error, response, body) {

    image = new Buffer(body, 'binary');

    db.images.insert({ filename: 'google.png', imgData: image}, function (err) {

        // handle errors etc.

    });

})

Now that you have clarified that request buffer's the response any idea on how I can properly save the image without a corruption.

回答1:

The request module buffers the response for you. In the callback, body is a string (or Buffer).

You only get a stream back from request if you don't provide a callback; request() returns a Stream.

See the docs for more detail and examples.

---

request assumes that the response is text, so it tries to convert the response body into a sring (regardless of the MIME type). This will corrupt binary data. If you want to get the raw bytes, specify a null encoding.

request({url:'http://google.com/doodle.png', encoding:null}, function (error, response, body) {
    db.images.insert({ filename: 'google.png', imgData: body}, function (err) {

        // handle errors etc.

    }); 
});

回答2:

var options = {
    headers: {
        'Content-Length': contentLength,
        'Content-Type': 'application/octet-stream'
    },
    url: 'http://localhost:3000/lottery/lt',
    body: formData,
    encoding: null, // make response body to Buffer.
    method: 'POST'
};

set encoding to null, return Buffer.

回答3:

Have you tried piping this?:

request.get('http://google.com/doodle.png').pipe(request.put('{your mongo path}'))

(Though not familiar enough with Mongo to know if it supports direct inserts of binary data like this, I know CouchDB and Riak do.)

回答4:

Nowadays, you can easily retreive a file in binary with Node 8, RequestJS and async await. I used the following:

const buffer = await request.get(pdf.url, { encoding: null }); 

The response was a Buffer containing the bytes of the pdf. Much cleaner than big option objects and old skool callbacks.