Upgrade in Place

This specification is written with WordPress’s “upgrade in place” system in mind. Conceptually it will be similar but we should not reuse its code due to its GPL licensing.

Considerations

• The system MUST determine that a new version is available.
• The system SHOULD only download the updated/new files and not the entire package.
• The system SHOULD work if the local files are writable by the webserver user.
• The system SHOULD apply core updates with no additional configuration.
• The system SHOULD apply updates to its modules with no additional configuration.
• The system SHOULD apply updates to its Add On modules with no additional configuration.
• The system MUST always set reasonable (non-breaking) defaults for any new/modified configuration settings.
• The system MUST remove deleted files.

WordPress’s Flow

• Check requirements
• Take a backup
• Disable plugins
• Ready to Update
• Automatic Update
• Manual Update - ‘‘aka what we do now’’
  • Replace WordPress files
  • Remove .maintenance file
  • Update your installation
  • Do something nice for yourself
• Final Steps
• Troubleshooting

Web2project’s proposed Flow

• Check central repository for core system updates
• Check requirements
  • Check PHP Version
  • Check libraries
  • Check database version
  • Check file ownership
• Put into offline state
• Make database backup
• Disable non-core modules
• Move old files
• Download updated files
• Place updated files in proper locations
• Apply core updates
• Check repository for add on module updates - [http://developer.github.com/v3/repos/#list-tags Tag Information]
• Apply module updates
  • List modules
  • Determine required updates
  • Check requirements
  • Apply updates
• If failure
  • Roll back updates?
  • Restore original files?
• Delete dead files
• Put into online state