스트림

https://github.com/ashtuchkin/iconv-lite/wiki/Use-Buffers-when-decoding

ashtuchkin/iconv-lite

Streaming

You can stream any response to a file stream.

 

request('http://google.com/doodle.png').pipe(fs.createWriteStream('doodle.png'))

 

You can also stream a file to a PUT or POST request. This method will also check the file extension against a mapping of file extensions to content-types (in this case application/json) and use the proper content-type in the PUT request (if the headers don’t already provide one).

 

fs.createReadStream('file.json').pipe(request.put('http://mysite.com/obj.json'))

Request can also pipe to itself. When doing so, content-type and content-length are preserved in the PUT headers.

 

request.get('http://google.com/img.png').pipe(request.put('http://mysite.com/img.png'))

 

Request emits a "response" event when a response is received. The response argument will be an instance of http.IncomingMessage.

 

request .get('http://google.com/img.png') .on('response', function(response) {
    console.log(response.statusCode) // 200
     console.log(response.headers['content-type']) // 'image/png'
}) .pipe(request.put('http://mysite.com/img.png'))

To easily handle errors when streaming requests, listen to the error event before piping:

 

request .get('http://mysite.com/doodle.png') .on('error', function(err) {
    console.error(err)
}) .pipe(fs.createWriteStream('doodle.png'))

 

Now let’s get fancy.

 

http.createServer(function (req, resp) {
    if (req.url === '/doodle.png') {
        if (req.method === 'PUT') {
            req.pipe(request.put('http://mysite.com/doodle.png'))
        } else if (req.method === 'GET' || req.method === 'HEAD') {
            request.get('http://mysite.com/doodle.png').pipe(resp)
        }
    }
})

 

You can also pipe() from http.ServerRequest instances, as well as to http.ServerResponse instances. The HTTP method, headers, and entity-body data will be sent. Which means that, if you don't really care about security, you can do:

 

http.createServer(function (req, resp) {
    if (req.url === '/doodle.png') {
        const x = request('http://mysite.com/doodle.png')
        req.pipe(x) x.pipe(resp)
    }
})

 

And since pipe() returns the destination stream in ≥ Node 0.5.x you can do one line proxying. :)

req.pipe(request('http://mysite.com/doodle.png')).pipe(resp)

Also, none of this new functionality conflicts with requests previous features, it just expands them.

 

const r = request.defaults({'proxy':'http://localproxy.com'})
http.createServer(function (req, resp) {
    if (req.url === '/doodle.png') {
        r.get('http://google.com/doodle.png').pipe(resp)
    }
})

 

You can still use intermediate proxies, the requests will still follow HTTP forwards, etc.