Pepr Filters

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Filters are functions that take a AdmissionReview or Watch event and return a boolean. They are used to filter out resources that do not meet certain criteria. Filters are used in the package to filter out resources that are not relevant to the user-defined admission or watch process.

When(a.ConfigMap)
  // This limits the action to only act on new resources.
  .IsCreated()
  // Namespace filter
  .InNamespace("webapp")
  // Name filter
  .WithName("example-1")
  // Label filter
  .WithLabel("app", "webapp")
  .WithLabel("env", "prod")
  .Mutate(request => {
    request
      .SetLabel("pepr", "was-here")
      .SetAnnotation("pepr.dev", "annotations-work-too");
  });

Filters

  • .WithName("name"): Filters resources by name.
  • .WithNameRegex(/^pepr/): Filters resources by name using a regex.
  • .InNamespace("namespace"): Filters resources by namespace.
  • .InNamespaceRegex(/(.*)-system/): Filters resources by namespace using a regex.
  • .WithLabel("key", "value"): Filters resources by label. (Can be multiple)
  • .WithDeletionTimestamp(): Filters resources that have a deletion timestamp.

Notes:

  • WithDeletionTimestamp() is does not work on Delete through the Mutate or Validate methods because the Kubernetes Admission Process does not fire the DELETE event with a deletion timestamp on the resource.
  • WithDeletionTimestamp() will match on an Update event during Admission (Mutate or Validate) when pending-deletion permitted changes (like removing a finalizer) occur.