Creating a collection

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see also: creating an activity

Overview

The OLPC Library is the set of content and materials (outside of the core OS and Activities) that ships with the XO laptops and school servers. In order to add your content to this repository, you must create a self-contained bundle for your content. This page is a proposed spec for such a bundle, providing the information you need to select, format, and package a content bundle.

Note: These instructions explain how to package browsable content for the OLPC library. Materials in a content bundle 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, skip down to the FAQ.

Content bundles unpack into a directory under /home/olpc/Library.

Feedback

As you create your bundle, please note any puzzles or problems you encounter, and any thoughts for improvement you might have. The process and format is a new one, and feedback helps improve it. One place to do that is on the Talk:Creating a content bundle page.

Selecting Content

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

Size 
How big is your collection? If the size of your entire collection is between 5-20MB, you're all set. Otherwise, you'll need to make two bundles-- one bundle of 5-20MB for use on individual laptops, and a second bundle of unlimited (but reasonable) size for inclusion on each school's library server.
Quality 
Does your collection have a rating system in place? If so, consider including only top-rated material in your content bundle. 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

Add explanatory info about the browser and how content is viewed on the XO...

Once you've determined the material you'd like to include in your content bundle (or, again, bundles-- since in many cases, you'll have to make two), you'll need to format it for use on the XO.

File Formatting

The first step of this process is to make sure that your collection is formatted in a file format that is supported by the library. (Other file formats may be supported on the XO, but not within the library). The following is a list of file formats supported by the library:

Text 
.txt, .doc, .abw - These formats can be read by AbiWord and will launch it from the browser. AbiWord will write .abw files.
.pdf - This can be ready by xbook, which launches automatically from the browser when following a link to a pdf.
Multimedia document with layout 
.html - Parsed by the browser. Source will soon be viewable.
.pdf - Read by xbook.
Formatted text 
.xml, .rss - Read by the browser and by penguinTV (as feeds).
Images 
.jpeg, .gif, .png - These can be viewed by many applications, including the browser.
.svg - 99% supported.
Music 
.csound - This will be playable by TamTam... currently its XO build doesn't provide a way to save or load sound files, however.
.ogg - See other common audio formats below; can be played by Helix or Gstreamer, not part of the current build.
.mp3, .wav - These can be played by Helix or Gstreamer, standalone or as a browser plugin, when they are installed.
.rm, .ra - This can be played by the Helix plugin when installed with a RealAudio codec.
Currently, audio files selected in the browser will launch a player if it is present.
Video 
.ogg - Can be played by Helix or Gstreamer, standalone or as a plugin. A Helix activity is now in the build. can now be downloaded in a few steps. To play video, please download this activity along with some videos (see for instance this video).
.mpeg, .mov, .wmv, .rm - See above.
Helix 
The Helix Media Activity has more information about media activity
Python 
The Develop activity will provide one way to view python files; the 'view source key' another.
Javascript 
This will viewable the same way page source can be viewed through the browser.
Etoys projects 
.pr files automatically launch etoys from the browser.

If you have a question about a file format that is not listed above, ask it on the talk page.

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).

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.

Disk usage

The XO's filesystem invisibly compresses files (poorly) to save space. So you may be using less disk space than you think. Text files are compressed about 50%. Other media are basically unchanged. If you are curious, there are somewhat difficulty to apply instructions in JFFS2 to measure likely disk usage.

Packaging Content

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

Bundle Structure

Sample index.html file: Stories. This index page uses the default library.css file. Source
Sample index.html file: International Children's Digital Library. This index page uses its own css files. Source

A content bundle is a directory compressed as a .zip file, renamed to end in .xol. Each content bundle must contain an index page called index.html, as well as a subdirectory called library that contains certain configuration files. Here is an example of a content bundle for a collection called "Dictionary":

Dictionary.xol/
    A/
        aardvark.html
        abacus.html
        acacia.html
    B/
        balloon.html
    C/
    ...
    library/
        library.info
        library-dictionary.jpg
        library.xml
        library.css
        contents
        contents.sig
    index.html
Dictionary.xol/ 
This is the "content" directory. It contains the content of the collection, as well as the library folder and the (optional) index.html file. See below for additional information about the index.html file.
library/ 
This directory contains all the metadata associated with the collection. It includes several configuration files which are discussed below in configuration files. The contents and contents.sig are manifest and credential files for the entire bundle contents (excepting the contents and contents.sig files themselves), as described by the Manifest Specification.
index.html (optional) 
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. If library.xml is present, the index page is automatically generated from that file. Otherwise, a static index.html page must be provided.
At right are two examples of index.html pages. The first is a standard index page auto-generated from a library.xml file using the default library style sheet. The second is an index page adapted from a pre-existing digital collection that uses its own organization scheme and style sheets. For additional examples of index pages, visit the online version of the OLPC Library. For information about various configurations of index pages, xml files, and style sheets, keep on reading!
Note: XML automation is not yet in place, so for now, content bundles MUST provide a static index.html page.

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. Library.info is the generic version, with information about required and optional entries.
library-dictionary.jpg (optional)
This is the icon that represents the collection in the library navigation sidebar. The icon should have the same name as the collection's .xol file, except with library- at the front. The icon can be in any number of supported file formats, including SVG, JPEG, PNG, and GIF. See Choosing image formats for more information.
Note: This may not need to exist, since icons appear at the category level, not the level of individual collections.
library.xml (optional)
If you choose not to provide a customized index.html page for your collection, you must provide this file. Sample library.xml file is an example. Library.xml is the generic version, with information about various elements and attributes.
library.css (optional)
If you choose not to provide a customized index.html page for your collection but would still like to customize the look and feel of your collection, you can include a library.css file in your content bundle. Sample library.css file is an example. Library.css is the generic version, with information about customizable classes and IDs.
Note: If you do not provide your own style sheet, the default values will be used.

Language and Localization

Library localization is still in development. At this point, just indicate the language(s) of your collection in the locale field of the library.info file.

Packaging Instructions

Here is a step-by-step guide to packaging your content bundle:

1. Look at your content, and make sure that no top-level directories are named library/.

2. Make a directory for your content, with the name you want to give your bundle. (Let's call it dictionary/ for the sake of example.)

3. Copy your content files (with any folder structure you like) into dictionary/.

4. Within dictionary/, 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. If you would like to supply an icon for your content bundle (see configuration files above), copy this icon (.svg, .jpg, .gif, or .png) into the library/ directory and rename it library-dictionary (with the appropriate format suffix).

7. Decide whether:

  • You want to use standard OLPC formatting (possibly with minor changes to colors and styles) in displaying your content on the XO.
  • You want to customize the display children see when using the XO to view your content.

8a. If you want to use standard OLPC formatting:

1. Create a text file library.xml within library/.
2. For every item in your content bundle that you want displayed to students, include items in your library.xml file that mirror those in the example Library.xml file.
3. If you want to change the colors and styles of the OLPC formatting, create a text file library.css within library/that gives your preferred css.

8b. If you want to use your own customized formatting:

1. Create a text file index.html in dictionary/.
2. In index.html, write html code providing links to all your content items.

9. Then zip dictionary/, with all its subdirectories into a .zip file with the same name as your bundle (eg dictionary.zip).

10. Rename the zip file as a .xol file (e.g. dictionary.xol).

Voila! The .xol file is your content bundle.

FAQ

Can I package an activity as a content bundle?

Yes! Content bundles are designed to coexist with activity bundles. To package your activity as a content 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.