IANA Time Zone Database to iCalendar Translation Database

This repo tracks releases of the IANA Time Zone Database together with the corresponding translations to the iCalendar format (as defined in RFC 5545).

The translation is performed using libical's VZIC utility.

Updating to a new release of the Time Zone Database

The intended usage is as follows:

• Upon a new release of the IANA Time Zone Database update settings.config. Update VZIC_RELEASE_NAME to match the name of the new release (e.g. 2022a).
• Commit and push the change to GitHub.

This will trigger a GitHub Workflow that does the following

• Download the specified version of the IANA Time Zone DB.
• Checkout, build and run vzic
• Merge the newly generated zoneinfo with the previous version, in order to keep TZIDs of unchanged time zones.
• Commit and push the updated tzdata and zoneinfo back to the repo on GitHub.

Creating a release

To create a new release:

• Bump and push VZIC_RELEASE_NAME as outlined above.
• Create a tag named release_$VZIC_RELEASE_NAME on the commit created by GitHub Actions.
• Create a GitHub release with the same name on the new tag.
  • Add the build artifacts from the automatic build (should be tzdata$VZIC_RELEASE_NAME.tar.gz and zoneinfo-$VZIC_RELEASE_NAME.tar.gz).