Helm Lifecycle Hooks
A Helm release undergoes several different phases during its lifetime. The first phase, install, occurs when the Helm chart is first installed. The second phase, upgrade, occurs when the Helm release is updated by either updating values or the Helm chart itself. At a later point, a Helm user may need to execute the rollback phase, which reverts the Helm release to an earlier state. Finally, if a user needs to delete the Helm release and its associated resources from the Kubernetes cluster, users must execute the uninstall phase.
Each phase is powerful on its own, but to provide additional capabilities around the release lifecycle, Helm features a hooks mechanism that allows custom actions to be undertaken at different points within a release cycle. For example, you may use hooks to do the following:
- Perform operations on a database, such as back up after upgrading or restoring a chart from a previous snapshot during a rollback.
- Fetch secrets from...