development.md

CMO Development

Run CMO Locally

Assumptions

• Should have a cluster running
• Has setup Go development env

Build and Run CMO

The make target run-local builds the operator and runs CMO locally

export KUBECONFIG=/path/to/kubeconfig/file
make run-local

Modify jsonnet

TL;DR:

1. build operator
2. use hack/local-cmo.sh to run the operator
3. modify assets/yamls
4. backport the changes to jsonnet

Sometimes we may not want to rebuild the operator. E.g. you may need to figure out how the stack behaves after applying a change to generated kubernetes manifest. In other words, to modify the YAML in assets/ directory directly without needing to change the jsonnet/ or the vendored jsonnet files.

In these cases it is easier to change those yaml files manually, run the operator (with those changed files) and later tweak jsonnet, than to figuring out which parts of jsonnet code you may need to change to fix an issue.

It is easier to follow the following workflow

Setup

1. Start openshift cluster ( e.g. using cluster-bot )
2. export KUBECONFIG=/path/to/kubeconfig
3. Build operator - make operator

Amend Assets

1. Amend yaml files in assets/ directory
2. Run hack/local-cmo.sh (does not build the operator)
3. ☝☝☝ rinse and repeat

Finally:

1. Port the changes back to jsonnet or vendored jsonnet

NOTE:

For some resources (see corresponding CreateOrUpdateXXX), removing a label/annotation needs to be done across two OCP releases:

• In the first release, you should add the suffix "-" to the relevant annotation/label. CMO will then delete that annotation/label on the Kubernetes API.
• In the second release, you can remove that annotation/label from the resource manifest under assets/.

Updating individual vendored jsonnet code

NOTE: jb update <repo-url>/<jsonnet-subdir> doesn't seem to work since it does not update the dependencies (at the time of writing)

Steps to update a bundle e.g. kube-prometheus:

cd jsonnet

Edit jsonnetfile.json and remove everything except the bundle you want to update E.g. remove everything but kube-prometheus from the jsonnetfile.json file

jb update

git add -p only the changes to the version and sum. E.g. the diff would show as follows, add only those ignore the bundles that got deleted

diff --git a/jsonnet/jsonnetfile.lock.json b/jsonnet/jsonnetfile.lock.json
index 6d5adc26..eead7874 100644
--- a/jsonnet/jsonnetfile.lock.json
+++ b/jsonnet/jsonnetfile.lock.json
@@ -28,8 +28,8 @@
           "subdir": "grafonnet"
         }
       },
-      "version": "3082bfca110166cd69533fa3c0875fdb1b68c329",
-      "sum": "4/sUV0Kk+o8I+wlYxL9R6EPhL/NiLfYHk+NXlU64RUk="
+      "version": "05fb200ee1a1816fc1b4c522071d5606d8dd71c1",
+      "sum": "mEoObbqbyVaXrHFEJSM2Nad31tOvadzIevWuyNHHBgI="
     },

Revert back the changes to jsonnetfile.json and jsonnetfile.lock.json

git restore --  jsonnetfile.json jsonnnet.lock.json

Now you should have a jsonnetfile.lock.json that has only the updates to the bundle kube-prometheus. Remove the vendor and reinstall all bundles.

# reinstall all jsonnet based on the new lockfile
rm -rf vendor ; jb install

# Now you should have only the changes that is part of latest kube-prometheus
cd ..
make generate
git add everything and commit