What is a Contribution/Addon/Plugin?

Acceptable Contributions

Addon/Contribution Requirements

• License: Must be GPL, since it's integrating into Zen Cart® core code, which is GPL. A complete copy of the license should be included in the contribution files, preferably as a separate file. If an addon is free-standing (ie: doesn't use *any* existing Zen Cart® files in order to operate) then it can be licensed under another license provided that license is fully compatible with GPL.
  
  You can find the GPL license details at:  http://www.gnu.org/licenses/licenses.html#GPL
  
  
• File Format: Contributions should be submitted in .ZIP format wherever possible for maximum compatibility to those who would download it (other compression formats are harder to use and less likely to have readily-available support for decompressing).
  
  
• File Size: The file should be as SMALL AS POSSIBLE. Excessively large graphics or PDF files should be avoided.
  
  
• Documentation: See "Documentation Requirements" below.
  
  
• Support: A support thread in the appropriate Addons/Contributions area of the Zen Cart® support forum should be opened following activation of a submitted contribution, where free support for that addon will delivered by the author and the community at large. Support for the addon should take place on the Zen Cart® forum.
  
  
• Contents:  
• Documentation files (see "Documentation Requirements" below).
• PHP files: The zipped distribution should contain a complete directory structure of files which should be added/edited/merged to effect implementation of the contribution.  The built-in override system should be used where possible.
• SQL files: If there are database changes required, an SQL file should be supplied containing any SQL commands which need to be run by the person installing the contribution.  
  An "uninstall" SQL script should be included as well so the end user can uninstall the SQL changes if they choose to remove the contribution.
  
  Any included .SQL files should be written without the use of database table-prefixes (such as "zen_"), since a default Zen Cart install doesn't use any such prefixes.
    
  NOTE: More advanced module writers may elect to have built-in SQL setup capability, as long as uninstall instructions/scripts are provided.
  
  
• Updates: If you are submitting an update to a contribution, please be sure to include the full set of files comprising that contribution. There should not be a need to install a prior version before installing your update. Each submission should be complete.

Unacceptable Submissions

1. It is *not* acceptable to submit crippled modules which are only teasers for paid services. ie:  a "limited" module with a sales pitch for a "full featured" commercial add-on is not permitted.
2. Having "donate to me" buttons in the add-on, either admin-side or storefront-side or is not permitted. A single statement about where to send donations may be added to the documentation, but should be discrete and not plastered all over the place.
3. Connectors to commercial services, such as embedded affiliate links or referral tracking links are not permitted.
4. In the interest of protecting the end-user's privacy and identity, any sort of call-home capability is forbidden, whether disclosed or not. 

Documentation Requirements

1. Complete documentation for the contribution must be contained in the contribution's distribution zip file, preferably in a file named "README-addonnamehere.TXT". Using a URL shortcut/link to point to another website for readme and/or install/uninstall documentation is not acceptable.
2. The author should be acknowledged - and a single link to their site is acceptable, as is a tasteful request for donations (whereas a single statement about where to send donations is acceptable).
3. Prior authors/contributors should be acknowledged.
4. Documentation should include clear steps outlining what to do once the contribution has been unzipped, including where to put the unzipped files and how to do any database updates/changes.
5. Documentation should be written with the "newbie" in mind ... ie: Don't make assumptions that the person using the contribution has any more understanding than how to unzip the file. This helps address the lowest-common-denominator skill-set and helps minimize support questions which can cause frustration and time drain on the author to supply support.
6. Documentation should include uninstall instructions in case someone wants to cleanly remove the addon from their store ... without breaking normal operation or leaving old fragments/data behind.  This should address any files to be removed, any folders to be removed, any permissions changes to be undone, and any SQL changes/deletions applicable to the addon.
7. Obfuscating or encrypting (such as via IONCube, Zend Guard, etc.) is *not* acceptable.
   
   

Submission