Reconciler

Overview

The Reconciler is a central system to reconcile Kyma clusters.

Run Reconciler locally (Mac OS)

Follow these steps to run Reconciler locally:

Build the Reconciler binary:
```
make build-darwin 
```
Run Reconciler.
CAUTION: At the moment, reconciliation with default values will fail. You must specify additional parameters:
```
./bin/mothership-darwin local --value global.ingress.domainName=example.com,global.domainName=example.com
```
We recommend specifying your own component list by using the components flag. By default, Reconciler installs all components listed in the components.yaml file.
```
 ./bin/mothership-darwin local --components tracing,monitoring
```

Testing

Unit tests

To execute unit tests, use the make test target:

  make test

Integration test

Integration tests have a higher resource consumption compared to unit tests. You must define the environment variable KUBECONFIG that points to a test Kubernetes cluster.

Be aware that the integration test suite installs and deletes Kubernetes resources during the test run.

To execute the integration tests, execute the make test-all target:

 make test-all

Adding a new component reconciler

If a custom logic must be executed before, during, or after the reconciliation of a component, component reconcilers are required.

The reconciler supports component reconcilers, which handle component-specific reconciliation runs.

To add another component reconciler, execute the following steps:

Create a component reconciler by executing the script pkg/reconciler/instances/reconcilerctl.sh.

Provide the name of the component as parameter, for example:
```
pkg/reconciler/instances/reconcilerctl.sh add istio
```
The script creates a new package including the boilerplate code required to initialize a new component reconciler instance during runtime.
Edit the files inside the package
- Edit the file action.go and encapsulate your custom reconciliation logic in Action structs.
- Edit the $componentName.go file:
  - Use the WithPreReconcileAction(), WithReconcileAction(), WithPostReconcileAction() to inject custom Action instances into the reconciliation process.

Re-build the CLI to add the new component reconciler to the reconciler start command.

The reconciler start command is a convenient way to run a component reconciler as standalone server.

Example:

 # Build CLI
 cd $GOPATH/src/github.com/kyma-incubator/reconciler/
 make build-darwin
 
 # Start the component reconciler (for example, 'istio') as standalone service
 ./bin/reconciler-darwin start istio
 
 # To get a list of all configuration options for the component reconciler, call: 
 ./bin/reconciler-darwin start istio --help

Add component name to the list in the Helm chart values.yaml and update the image version to the latest one after you merge your changes.