Api changes between v0.8 and v0.10

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Changed

• Streams Interface

  • Readable, Writable, Duplex, and Transform base classes added.
  • Readable streams use a read() method instead of emitting 'data' events right away.
  • Adding a 'data' event handler, or calling pause() or resume() will switch into "old mode".
    • This means that data event handlers won't ever miss the first chunk if they're not added right away, and pause() is no longer merely advisory.
  • If you don't consume the data, then streams will sit in a paused state forever, and the end event will never happen.

• The uv_after_work_cb signature has changed to take a second integer argument indicating status. For backwards compatibility, explicitly cast the 4th argument to uv_queue_work. Example

• process.nextTick happens at the end of the current tick, immediately after the current stack unwinds. If you are currently using recursive nextTick calls, use setImmediate instead.

• -p --print command line switch implies -e --eval

• url: Parsed objects always have all properties, but unused ones are set to null. Example:

  // v0.8
  > url.parse('http://foo')
  { protocol: 'http:',
    slashes: true,
    host: 'foo',
    hostname: 'foo',
    href: 'http://foo/',
    pathname: '/',
    path: '/' }
  
  // 0.10
  > url.parse('http://foo')
  { protocol: 'http:',
    slashes: true,
    auth: null,
    host: 'foo',
    port: null,
    hostname: 'foo',
    hash: null,
    search: null,
    query: null,
    pathname: '/',
    path: '/',
    href: 'http://foo/' }

• Domain-added properties on error objects are camelCase instead of snake_case

• path.resolve and path.join throw a TypeError on non-string input

• dgram.Socket#bind() is always asynchronous now. If you have code that looks like this:

  var s = dgram.createSocket('udp4');
  s.bind(1234);
  s.addMembership('224.0.0.114');

  You have to change it to this:

  var s = dgram.createSocket('udp4');
  s.bind(1234, function() {
    s.addMembership('224.0.0.114');
  });

• The EventEmitter constructor initializes various properties now. It still works fine as an OOP inheritance parent, but you have to do inheritance properly. The Broken-Style JS inheritance pattern will not work when extending the EventEmitter class. This inheritance style was never supported, but prior to 0.10, it did not actually break.

  // Broken-Style Inheritance, which has never been safe or wise
  // but is shown on many broken tutorials around the web.
  function Child() {}
  Child.prototype = new Parent(); // <-- NEVER EVER DO THIS!!
  // If you see anyone doing this in any javascript library ever,
  // post a bug telling them that it is a huge terrible mistake!
  // Inheriting from a class should not call that class's ctor
  // on the prototype shared with EVERY instance of the child class!
  
  // Correct-Style Inheritance
  function Child() {}
  Child.prototype = Object.create(Parent.prototype, {
    constructor: {
      value: Child,
      enumerable: false,
      writable: true,
      configurable: true
    }
  });
  // "Gee that's a lot of lines! I wish there was a helper method!"
  // There is.  Do this:
  util.inherits(Child, Parent);

Added

• Streams - Added base classes for Readable, Writable, Duplex, and Transform
• Streaming interfaces for Crypto API
• process: add getgroups(), setgroups(), initgroups()
• crypto: getHashes() getCiphers()
• http: add response.headersSent property
• events: 'removeListener' event
• setImmediate() and clearImmediate() functions
• string_decoder: the decoder.end() function was added