Activities/Wikipedia/HowTo

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"Crear uno, dos, tres... mil Wikipedias" Comandante Ernesto Wales

How to Create a new wikipedia activity or update a existing activity

This page describes how to create the data files needed to create a wikipedia activity like Wikipedia es or Wikipedia en

The general idea is download a xml file with a dump (backup) with the state of the wikipedia pages, and process it to select a number of pages, and compress them, to include in a activity. Optionally, is possible download the images used in that pages.

You will need a computer with a lot of space on disk, and a working Sugar environment. May be using packages provided by your linux distribution or in a virtual machine. The wikipedia xml file is big (almost 6 GB to the spanish wikipedia, bigger in english), and you need more space to generate temporary files. The process takes a lot of time too, but is automatic, you only need check states at finish of every stage.

This page is a work in progress. If you have doubts or the information provided is not good enough, please contact me at gonzalo at laptop dot org and I will try to improve it.

Download the wikipedia base activity

You will need download the wikipedia base from http://dev.laptop.org/~gonzalo/wikibase.zip. This file include the activity and the tools to create the data files.

You need create a directory in your Activities directory for example WikipediaEs.activity and unzip wikibase.zip inside.

Download a dump

Wikipedia provide a almost daily xml files dump for every language. This test was done with the spanish dump. The file used was eswiki-20111112-pages-articles.xml.bz2 from http://dumps.wikimedia.org/eswiki/20110810/ You need create a directory inside the create activity and download the wikipedia dump file

The first two letters from your directory must be the language code example: es_es or en_us

mkdir es_lat
cd es_lat
bzip2 -d eswiki-20111112-pages-articles.xml.bz2

Process the dump file

You need edit the file tools2/config.py, and modify the variable input_xml_file_name. If you are creating a wikipedia in a different language to spanish, modify the values of the other variables.

After save the config.py, you can process the dump file:

../tools2/pages_parser.py

The process will generate files with the same prefix than the uncompressed xml file. This first process will create the following files:

eswiki-20111112-pages-articles.xml.links
eswiki-20111112-pages-articles.xml.page_templates
eswiki-20111112-pages-articles.xml.redirects
eswiki-20111112-pages-articles.xml.templates

If you want have more information, can use the option "--debug" to create the files prefix.all_pages, prefix.blacklisted and prefix.titles and help you to research about the process.

With the spanish file and a little more to 2.3M pages, this process takes aprox 1:30 hours

Make a selection of pages

To create a selection of pages to be included in the wikipedia activity, you need create two files: favorites.txt and blacklist.txt The two files are a list of titles of pages.

The criteria used to select the pages is: all the pages in favorites.txt will be included and all the pages linked from this pages too, except the pages in the file blacklist.txt

Our wikipedia activity have a static index page (static/index_lang.html) and you can create your own index page. I have created my favorites.txt with all the pages linked from the index page (in the case of spanish 130 pages) and 300 pages more selected from a statistic of most searched pages in wikipedia (http://stats.grok.se)

There are not a linear relation between number of favorite pages and final number of pages selected, but as reference, you can use this numbers:

           Favorites           Total selected pages
               130                     15788
               431                     45105
               544                     63347

The files favorites.txt and blacklist.txt should be in the same directory than the .xml file

To create the selection do:

../tools2/make_selection.py

After you have created the selection, you can look at the list of pages in the file pages_selected-level-1 and modify your favorites.txt and/or blacklist.txt files and rerun the process if you want modify the selection.

Create the index

../tools2/create_index.py 

This process is faster and when finished you can do a basic test:

../tools2/test_index.py page_title

and this will show you the content in wiki format of the selected page. At this stage, the process will be slow, because need to search for every template and do all the templates substitutions. To have faster results we will apply templates substitutions in all the pages.

Optimze the data and download images

To expand the templates need go out of the data directory:

cd ..
./tools2/expandtemplates.py es_lat

If you want include images in your wikipedia activity can go again to your data directory and do:

cd es_lat
../tools2/download_images.py

This command will download the images included in the pages in favorites.txt If you want include the images in all the pages, should do:

../tools2/download_images.py --all

A option --cache_dir=directory is available if you have images already downloaded in another directory to acelerate the process.

Modify your activity to use the data files

You need can modify the file activity_es.py and modify the lines:

       self.WIKIDB = 'es_new/eswiki-20111112-pages-articles.xml'
       self.HOME_PAGE = '/static/index_es.html'

to point to your new data files or create a new different file, for example activity_pt.py.

If you create a new file, you will need modify the file activity/activity.info to point to this new file.

You can create a new icon too, or modify the existing activity/activity-wikipedia-es.svg file.