drop streamify, add downloadFromInfo

README.md

@@ -34,7 +34,7 @@ ytdl(url, { filter: function(format) { return format.container === 'mp4'; } })
 
 The returned readable stream emits these additional events.
 
-### Event: 'info'
+#### Event: 'info'
 * `Object` - Info.
 * `Object` - Format.
 
@@ -48,10 +48,17 @@ Use this if you only want to get metainfo from a video.
 
 `options` gets passed to the `request()`, it can also have a `downloadURL` property set to `true` if you want ytdl to include the download url instead of the regular one. In some cases, a signature needs to be deciphered, and will require ytdl to make additional requests.
 
-### ytdl.cache
+### ytdl.downloadFromInfo(info, options)
 
-A [memory cache](https://github.com/hij1nx/EventVat) is used to store information about recently retrieved videos. This is used to prevent double requests on videos that you want to retrieve the info of, and then download.
+Once you have received metadata from a video with the `getInfo` function,
+you may pass that `info`, along with other `options` to `downloadFromInfo`.
 
+The returned readable stream emits these additional events:
+
+#### Event: 'format'
+* `Object` - Format.
+
+Emitted when a format metadata has been chosen. `format.size` will also be available.
 
 # Install
 

lib/index.js

@@ -1,64 +1,95 @@
-var http      = require('http');
-var streamify = require('streamify');
-var request   = require('request');
-var _         = require('underscore');
-var getInfo   = require('./info');
-var crequest  = require('./crequest');
-var util      = require('./util');
+var http        = require('http');
+var PassThrough = require('stream').PassThrough;
+var request     = require('request');
+var _           = require('underscore');
+var getInfo     = require('./info');
+var crequest    = require('./crequest');
+var util        = require('./util');
 
+module.exports = ytdl;
+ytdl.getInfo = getInfo;
+ytdl.downloadFromInfo = downloadFromInfo;
 
 /**
  * @param {String} link
  * @param {Object} options
  * @return {ReadableStream}
  */
-var ytdl = module.exports = function ytdl(link, options) {
-  var stream = streamify({
-    superCtor: http.ClientResponse,
-    readable: true,
-    writable: false
-  });
-
+function ytdl(link, options) {
   options = options || {};
   options.downloadURL = true;
 
+  var stream = new PassThrough();
+
   getInfo(link, options, function(err, info) {
     if (err) {
       stream.emit('error', err);
-      stream.readable = false;
       return;
     }
 
-    var format = util.chooseFormat(info.formats, options);
-    if (format instanceof Error) {
-      stream.emit('error', format);
-      return;
-    }
-
-    var requestOptions = _.clone(options);
-    requestOptions.url = format.url;
-    if (requestOptions.range) {
-      requestOptions.url += '&range=' + requestOptions.range;
-    }
-    delete requestOptions.quality;
-    delete requestOptions.range;
-    delete requestOptions.filter;
-
-    // Start downloading the video.
-    var req = request(requestOptions);
-    req.on('response', function(res) {
-      if (res.statusCode !== 200) {
-        stream.emit('error', new Error('status code ' + res.statusCode));
+    downloadFromInfoCallback(info, options, function(err, format, videoStream) {
+      if (err) {
+        stream.emit('error', err);
         return;
       }
-
-      format.size = res.headers['content-length'];
       stream.emit('info', info, format);
+      videoStream.pipe(stream);
     });
-    stream.resolve(req);
   });
 
   return stream;
-};
+}
 
-ytdl.getInfo = getInfo;
+function downloadFromInfoCallback(info, options, callback) {
+  options = options || {};
+
+  var format = util.chooseFormat(info.formats, options);
+  if (format instanceof Error) {
+    // The caller expects this function to be async.
+    setImmediate(callbackWithFormatError);
+    return;
+  }
+
+  var requestOptions = _.clone(options);
+  requestOptions.url = format.url;
+  if (requestOptions.range) {
+    requestOptions.url += '&range=' + requestOptions.range;
+  }
+  delete requestOptions.quality;
+  delete requestOptions.range;
+  delete requestOptions.filter;
+
+  // Start downloading the video.
+  var req = request(requestOptions);
+  req.on('error', callback);
+  req.on('response', function(res) {
+    if (res.statusCode !== 200) {
+      callback(new Error('status code ' + res.statusCode));
+      return;
+    }
+
+    format.size = res.headers['content-length'];
+    callback(null, format, req);
+  });
+
+  function callbackWithFormatError() {
+    callback(format);
+  }
+}
+
+function downloadFromInfo(info, options) {
+  var stream = new PassThrough();
+  options = options || {};
+
+  downloadFromInfoCallback(info, options, function(err, format, videoStream) {
+    if (err) {
+      stream.emit('error', err);
+      return;
+    }
+
+    stream.emit('format', format);
+    videoStream.pipe(stream);
+  });
+
+  return stream;
+}

package.json

@@ -19,7 +19,6 @@
   "dependencies": {
     "jstream": "~0.2.7",
     "request": "~2.36.0",
-    "streamify": "~0.2.0",
     "underscore": "~1.6.0"
   },
   "devDependencies": {