Creating a collection

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If you would like to package a collection of mostly-static content for use on the XO, follow the instructions below to create a collection (sometimes called a library or content bundle). When you're done, you can add your new bundle to the Collections page so that it can be viewed and downloaded by children worldwide. Upon installation it will appear in the Library.

If you'd like to help out by creating collections but are unsure of where to begin, see the list of new bundle ideas.

Overview

The OLPC Library is the set of content and materials (outside of the core OS and Activities) that ships on the XO laptop and/or school server (the exact set of content shipped with the laptop is usually determined by the organization distributing the laptops within a specific country). In order to make your content available to OLPC projects worldwide, you must create a self-contained bundle for your content. This page describes the process of creating such a bundle, providing the information you need to select, format, and package a collection.

Note: These instructions explain how to package browsable content for the OLPC library. Materials in a collection that need to be run by an Activity other than Browse will have to have a mime-type registered with the Browse activity so they can launch from there. Activities may be part of content packages for the library as well, for instance as sample code to be read. For more information on packaging source code, as well as other questions you may have, skip down to the #FAQ.

Collections currently unpack into a directory under /home/olpc/Library. Future improvements to the current bundle format are intended to allow a single bundle to contain both an activity and a collection (including, for instance, default help/readme materials).

'If you plan to host your own bundles, please note the #bundle hosting guidelines.

Feedback

As you create your bundle, please note any puzzles or problems you encounter, as well as any thoughts for improvement that you might have. You can leave feedback on the Talk:Creating a collection page.

Selecting content

The first step to creating your collection is to determine what content should be included. In some cases, this is easy: everything! In other cases, there are additional considerations:

Size
How big is your collection? Keep in mind the limited disk space available on the XO. You may wish to bundle only a subset of your content, perhaps figuring out a way to make the content available entirity on the school server.
Note: The XO-1's filesystem invisibly compresses files to save space, so you may be using less disk space than you think. Text files are compressed about 50%. Other file formats are basically unchanged. If you are curious, there are (somewhat difficult to apply) instructions in JFFS2 to measure likely disk usage.
Quality
Does your collection have a rating system in place? If so, consider including only top-rated material in your collection. Otherwise, think about "curating" a selection of high quality material to be included in your bundle (or bundles).
Relevance
Is your entire collection relevant to children? If so, terrific! If not, consider including only material that will help children learn, explore, and expand their worlds.
Language issues
Does your collection contain material in multiple languages? We hope it does! To the greatest extent possible, please give preference to materials that exist in multiple languages, or that can be easily translated by our localization team.
Licensing issues
What kind of copyright exists on the material in your collection? Do you have legal permission to archive and distribute it? Please be sure to review the licensing terms of your collection. For guidance on licensing, see licenses.

Formatting content

Once you've determined the material you'd like to include in your collection, you'll need to format it for use on the XO.

File formats

The first step of this process is to make sure that all of the content you plan to include is accessible from a HTML index page, or a series of linked HTML pages. HTML is currently the only format directly supported by the library, but you can then include hyperlinks to files of any format supported by the activities present on the XO. When clicked, the content will be presented as a download, copied into the journal, then opened in the appropriate activity.


For example, for a simple content bundle including 5 PDF files, you would have to additionally write a HTML index page, providing hyperlinks and descriptions of the 5 PDF files that make up the bundle.

Visual formatting

The second step of the formatting process is to make sure that your collection displays correctly on the XO. The small screen can sometimes lead to unexpected formatting and display issues. Also test it with the screen rotated and in e-book mode (with the screen rotated and lowered).

The easiest way to test the visual display of your material is to view it on an XO. If you don't have access to an XO — or to another person who has one — you can install and run the Sugar emulator on your computer. Emulating the XO has installation instructions.

Packaging content

Once you've selected and formatted your content, the last thing to do is to package it as a bundle.

Bundle structure

A collection or library bundle is a directory compressed as a .zip file renamed to end in .xol. (.xo and .xol formats are planned to merge, in which case a collection in a bundle will be identified by the "library" subdirectory and its "library.info" file.)

Each bundle must contain a single top-level directory which has the same name as the bundle (minus the ".xol" extension). All other files in the bundle must be within this directory. The top-level directory must also contain a subdirectory called library that contains certain configuration files.

Here is an example of a library bundle for a collection called "dictionary.xol":

dictionary/
    A/
        aardvark.html
        abacus.html
        acacia.html
        ...
    B/
        balloon.html
        ...
    C/
    ...
    library/
        library.info
        library-dictionary.jpg
        contents
        contents.sig
    index.html
dictionary/
The top-level directory, which has the same name as the bundle itself (minus the ".xol" extension).
library/
This directory contains all the metadata associated with the collection. It includes several configuration files which are discussed below in configuration files.
index.html
This is the top-level navigation page for the collection. The index.html page is the page that is displayed in the main frame of the reader when a child selects the collection from the library sidebar.

Configuration files

The "library" directory contains all the metadata associated with the collection. It includes the following files:

library.info
The library.info file is a text file that follows a key/value pair format. It contains information about the source, version, language, and subject of the collection (among other things). Sample library.info file is an example and more-or-less the definitive documentation of this format, with information about required and optional entries.
You can use this web form to create a library.info file for your bundle.

Localization

Collections tend to rely much more heavily on text than code, and often the right way to localize something fully is to make a separate bundle for each language (even for some of the activity bundles that now have twenty localizations, the bulk of their size is taken up by their locale materials).

Currently, we do not offer tools for any other option. Simply indicate the language(s) of your collection in the locale field of the library.info file.

Packaging a collection

Step by step

  1. Make sure that no top-level directories in your content are named library/.
  2. Make a directory for your content, with the name you want to give your collection. (Let's call it omnium/ for the sake of example.)
  3. Copy your content files (with any folder structure you like) into omnium/.
  4. Within omnium/, make a second directory called library/.
  5. Within library/, create a text file called library.info and give it content as in the sample library.info file.
  6. Create a text file index.html in omnium/.
  7. In index.html, write html code providing links to all your content items.
  8. Zip up omnium/, with all its subdirectories into a .zip file with the same name as your bundle (eg omnium.zip).
  9. Rename the zip file as a .xol file (e.g. omnium.xol).

Voila! The .xol file is your collection's library bundle.

Bundle hosting

To host your own bundles, you must tell your web server about the bundle mime types Sugar expects. You need to add the following to your web-server configuration (/etc/apache/mime.types, or /etc/mime.types on Ubuntu systems):

 application/vnd.olpc-sugar      xo
 application/vnd.olpc-content    xol

If you want to host your bundles elsewhere, you are welcome to upload them to this wiki or to dev.laptop.org (you can [[requesting an account|request an account] there if you need shell access), which will set the mime-type properly when they are later downloaded.

FAQ

Can I repackage an activity as a library bundle?

Yes -- but only for the purposes of providing navigation through the elements of the activity, as opposed to actually executing it.

To package your activity as a library bundle, you just need to add the index.html page and the library directory (including relevant configuration files) to your existing activity bundle. Then, rename it as a .xol file, and you should be all set. If you are modifying a bundle on an XO, you will also need to move it from /home/olpc/Activities to /home/olpc/Library . As mentioned above, there are plans to merge the xo and xol formats, so that no repackaging is needed for a bundle to be interpreted in both ways.

How do you open an XOL file?

An XOL file is a zip file with .xol extension instead of .zip. You can extract the contents using any unzip utility. If you want to install a content bundle, you do it just like any other activity. Download it with the browser, then resume it from the Journal. The new bundle will show up the next time you open the Browse Activity or if you refresh the browser's homepage.

How do you uninstall a collection?

See Collections#Removing a collection.

How do I upload my collection to this wiki, and host it here?

You can upload it by clicking "Upload file" in the left margin, and entering the filename and description on the page that comes up. Then, after you hit the upload button, it'll be hosted on the OLPC Wiki. Then, to get it into the index of Collections, you can edit that page by hand as well. (you can also try using Semantic Mediawiki to add your entry to the table.)

See also