update readme with testing instructions

README.md

@@ -9,11 +9,46 @@ This repository holds all the necessary files to build rocks for the upstream ve
 
 The rocks on this repository are built with [OCI Factory](https://github.com/canonical/oci-factory/), which also takes care of periodically rebuilding the images.
 
-New versions of the rock are tested using [`goss`](https://github.com/goss-org/goss) (for the actual validation) and [`noctua`](https://github.com/lucabello/noctua) (to run the actual command).
+New versions of the rock are tested using [`goss`](https://github.com/goss-org/goss) and `kgoss`. To test manually, look at the [testing](#testing) section.
 
 Automation takes care of:
 * validating PRs, by simply trying to build the rock;
 * pulling upstream releases, creating a PR with the necessary files to be manually reviewed;
 * on PRs, validate the added (or modified) rocks by running them in a Kubernetes pod and testing them with `goss`;
 * releasing to GHCR at [ghcr.io/canonical/mimir:dev](https://ghcr.io/canonical/mimir:dev), when merging to main, for development purposes.
 
+
+## Testing
+
+**Requirements**: `kubectl` (classic), `microk8s`, `rockcraft`.  
+Make sure that you've run `microk8s enable registry`.
+
+Pack the rock and push it to the local registry:
+
+```bash
+# Pack the rock and push it to the local registry (replace the <variables>)
+rockcraft pack
+rockcraft.skopeo --insecure-policy copy --dest-tls-verify=false \
+  oci-archive:<rock_file> \
+  docker://localhost:32000/<rock_name>:<version>
+```
+
+### Testing with `kgoss`
+
+**Extra Requirements**: `goss`, `kgoss`.
+
+`kgoss` will run the rock in a temporary pod, copy the `goss` binary and checks to the container, and run them from the inside.
+
+```bash
+# Set GOSS_FILES_PATH to the `goss.yaml` folder (default: '.')
+kgoss run -i localhost:32000/<rock_name>:<version>
+```
+
+### Testing manually
+
+For manual exploration, you can run the rock in a pod with only `kubectl`:
+
+```bash
+kubectl run <pod_name> --image=localhost:32000/<rock_name>:<version>
+kubectl exec <pod_name> -it -- /bin/bash
+```