Mikeal's NodeJS Request modify body before piping

Question

I'm using mikeal's awesome request module for NodeJS. I'm also using it with express where I'm proxying a call to the API for getting around CORS issues for older browsers:

app.use(function(request, response, next) {
  var matches = request.url.match(/^\/API_ENDPOINT\/(.*)/),
      method = request.method.toLowerCase(),
      url;

  if (matches) {
    url = 'http://myapi.com' + matches[0];

    return request.pipe(req[method](url)).pipe(response);
  } else {
    next();
  }
});

Is there a way I can modify the body before I pipe the request's response back to express?

Answer 1

Based on this answer: Change response body before outputting in node.js I made a working example that I use on my own app:

app.get("/example", function (req, resp) {
  var write = concat(function(response) {
    // Here you can modify the body
    // As an example I am replacing . with spaces
    if (response != undefined) {
      response = response.toString().replace(/\./g, " ");
    }
    resp.end(response);
  });

  request.get(requestUrl)
      .on('response',
        function (response) {
          //Here you can modify the headers
          resp.writeHead(response.statusCode, response.headers);
        }
      ).pipe(write);
});

Any improvements will be welcome, hope it helps!

Answer 2

You probably want to use a transform stream. After some googling I found the following blog post.