Resources

Source: hello-pepr-store-resources

Pepr Store is backed by Kubernetes Custom Resources that can be accessed directly as PeprStore objects. Behind the scenes, the Pepr Store API (Store.setItem(), Store.getItem(), etc.) uses a Custom Resource Definition called PeprStore to persist data in the cluster. This example demonstrates how Store operations create and update PeprStore resources in Kubernetes.

Key Points

• All Store operations for a capability are persisted in a single PeprStore CRD
• The PeprStore resource lives in the pepr-system namespace
• Store keys can include special characters like :// (e.g., URLs)
• Store data is stored as key-value string pairs in the data field
• Store updates are batched and sent to the Kubernetes API at 5-second intervals
• The Store is eventually consistent, backed by etcd through Kubernetes

When to Use

Use this pattern when you need to:

• Inspect Store data directly using kubectl for debugging
• Understand how Store operations map to Kubernetes resources
• Verify that Store data is being persisted correctly
• Access Store data from outside your Pepr module
• Troubleshoot Store-related issues by examining the underlying CRD

Code Example

View full example on Github

When(a.ConfigMap)
  .IsCreated()
  .WithName("observe")
  .Watch(async function observeWatch() {
    Store.setItem("a", "1");
    Store.setItem("b", "2");
    Store.setItem("c", "3");
    await Store.setItemAndWait("https://observed", "yay");
    Log.info("observed");
  });

Example pod log output:

{"level":30,"time":1726798504518,"pid":16,"hostname":"pepr-watcher-6dc69654c9-5ql6b","msg":"observed"}

Viewing the PeprStore Resource

You can inspect the PeprStore Custom Resources using kubectl:

# List all PeprStore resources
kubectl get peprstores -n pepr-system

# Get detailed YAML output for a specific store
kubectl get peprstore <store-name> -n pepr-system -o yaml

Example PeprStore YAML:

After the Store operations execute, the PeprStore resource will contain:

apiVersion: pepr.dev/v1
kind: PeprStore
metadata:
  name: pepr-<module-uuid>-store-hello-pepr-store-resources
  namespace: pepr-system
data:
  a: "1"
  b: "2"
  c: "3"
  https://observed: "yay"

Tip

Learn more about the Pepr Store