rextract¶ ↑

A web scraping framework using Matt Thorley’s Dirt pattern.

The idea is that you

gem install rextract
rextract project new-scraping-project -j job1,job2

and it’ll create a new scraping project for you and create a template of scripts, spiders and parsers so you can quickly create scraping projects. The -j option creates a job folder with a spider and a parser for each named, comma-separated job.

Concepts¶ ↑

Spiders¶ ↑

Spiders inherit from Rextract::Browser which is essentially Mechanize with some helpers. You use Mechanize’s methods to get, post and do all the fancy browsing and create some methods to return the body content you want for given pages. Anything more complicated than a couple of xpaths or css selectors you should stick in a Parser.

The spider saves all the content scraped to disk by default in directories named by url and timestamp. This makes it so you can alter parsers w/o having to re-download the content.

Parsers¶ ↑

Parsers inherit from Rextract::Parser. You define methods with the prefix ‘parse_’ and they will all get called automagically and their data will return as a hash of results. When you create a new Parser object, pass in the body content into the .new() method, then call parse on the object.

Contributing to rextract¶ ↑

Contributions are super much appreciated!
Check out the latest master to make sure the feature hasn’t been implemented or the bug hasn’t been fixed yet
Check out the issue tracker to make sure someone already hasn’t requested it and/or contributed it
Fork the project
Start a feature/bugfix branch
Commit and push until you are happy with your contribution
Make sure to add tests for it. This is important so I don’t break it in a future version unintentionally.
Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.

Copyright and License¶ ↑

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.