rg3/youtube-dl — pull request #1198 by ravishi (2013-08-06 21:35:57+00:00)
Title: Add support for third-party extractors

Other packages can register new extractors through the `youtube_dl.extractors` setuptools entry-point.

For example:

```python
setup(
# ...
entry_points={
'youtube_dl.extractors': [
'myextractor = mypackage.extractor.MyExtractorIE',
],
},
)```

Once the package AND youtube-dl are installed, the registered extractor will work just like an ordinary extractor.

One issue that I didn't take into account while coding this is the order of the extractors. The extractors will be registered in the order defined by the `pkg_resources` algorithm, which is uknown to me.