(Advanced) Building an operator

Set up DevOps pipelines to build an operator and operator catalog

The Cloud-Native Toolkit provides Tekton pipelines to automate the process to build and deploy operator-based applications. The operator pipeline supports Ansible, Go, and Helm-based operators that have been built using the Operator SDK. The Cloud-Native Toolkit also provides a companion Tekton pipeline to build a custom Operator Lifecycle Manager catalog that simplifies deployment of the operators to a cluster.

The following steps will walk you through using the pipelines to build an operator and operator catalog and deploy them to a cluster.

Prerequisites

Operator SDK

The Tekton pipeline for building operators requires that the operator has been created by at least v1.0.0 of the Operator SDK but we recommend using the latest available (v1.3.0 at the time of this writing). The Operator SDK structure had a major architectural change with v1.0.0 and continues to have significant improvements made with each release.

If you do not have operator-sdk, follow the installation instructions to get it.

(Optional) Create your operator

These steps will walk you through building a simple operator following the Operator SDK quick-start guide. You can choose between Ansible

Go, orHelm quick start guides for the following example.

Note: If you already have an operator built with v1.0.0+ of the Operator SDK then you can skip to the next section.

The Ansible operator quick start seems to be the simplest way to get up and running quickly and exercise the Tekton pipelines. We’ve included the abbreviated steps from the Ansible quick start guide below.

Create a directory for your operator and change to that directory

mkdir memcached-operator
cd memcached-operator

Initialize the operator
```
operator-sdk init --plugins=ansible --domain=example.com
```
where:
- --plugins can be either ansible, go, or helm. If --plugins is not provided then it defaults to go
- --domain is the base domain name used for the Custom Resource Definition generated for the operator

Create an API for the operator

operator-sdk create api --group cache --version v1 --kind Memcached --generate-role

where:

--group is the api group for the CRD
--kind is the resource kind for the CRD
--version is the resource version for the CRD

Generate metadata for Operator bundle
```
make bundle
```
Answer the interactive questions

Create the README.md and initialize git repository

echo "# memcached operator" > README.md
git init
git add .
git commit -m "Initial commit"

Create a new remote git repository on a git server such as GitHub and copy the url

Push the local git repository to the remote GitHub repository

git remote add origin ${GIT_URL}
git push -u origin $(git rev-parse --abbrev-ref HEAD)

At this point you have enough of a functioning operator to try out the Tekton operator pipeline. If you want to explore the operator you have created and/or enhance its capabilities, there are more detailed instructions on the operator sdk page.

Register the operator pipeline

This step is similar to deploying an application.

1. Log into your Development Cluster from the command line

Before starting, make sure you have set up your development tools.

Log into the cluster with icc [cluster name|cluster nickname]

Run oc login $SERVER -u $OCP_USERNAME -p $OCP_PASSWORD

You should now be able to access the OpenShift console:

oc console

NOTE: If your workshop is on Code Ready Workspaces, follow the steps in Code Ready Workspaces Setup before logging in to the cluster. The remaining steps assume this step has already been performed. If you stop and then come back later it is a good idea to re-run this step again before proceeding

2. Create the operator development namespace

Before getting started, the development namespace/project needs to be created and prepared for the DevOps pipelines. This is something that would typically happen once at the beginning of a project when a development team is formed and assigned to the cluster.

This step copies the common secrets and configMaps that contain the CI/CD configuration from the tools namespace into the development namespace/project. This enables the pipelines to reference the values easily for your project.

oc sync ${OPERATOR_NAMESPACE}

3. Register the operator in a DevOps Pipeline

Start the process to create a pipeline using Tekton.

oc pipeline --tekton

The first time a pipeline is registered in the namespace, the CLI will ask for a username and Password/Personal Access Token for the Git repository that will be stored in a secret named git-credentials.
Username: Enter your GitHub user id
Personal Access Token: Paste your GitHub personal access token
The CLI will attempt to determine the runtime of your repository. It should detect that it is an operator and prompt you to select ibm-operator pipeline or ibm-operator-catalog pipeline. Select ibm-operator pipeline.
When registering a Tekton pipeline, the CLI also reads the available parameters from the pipeline and generates prompts for input. In this case, the option of scanning the built image for vulnerabilities is the only options. The scan is performed by the Vulnerability Advisor if you are using IBM Image Registry or by Trivy if another image registry is used. This scan is performed in “scan” stage of pipeline after “img-release” stage.
```
? scan-image: Enable the pipeline to scan the image for vulnerabilities?(Y/n)
```
To skip the scan, you have type “n” (No). Otherwise, type “y” (Yes) for performing Vulnerability Scanning on the image.
After the pipeline has been created,the command will set up a webhook from the Git host to the pipeline event listener.
Note: if the webhook registration step fails, it is likely because the Git credentials are incorrect or do not have enough permission in the repository.
When the command is completed it will present options for next steps. You can use the Tekton cli commands to inspect the pipeline run that has been created and tail the log and/or navigate to the provided url to see the pipeline running from the OpenShift console.

4. View your application pipeline

Open the OpenShift Web Console

oc console

From menu on the left switch to the Developer mode
Select dev project that was used for the application pipeline registration
In the left menu, select Pipelines

You will see your application DevOps pipeline now starting to build and once completed will look like the image below.

Register the operator catalog pipeline

The operator catalog repository is a simple repo used to keep track of the operator bundles that will be packaged together in the catalog. Even though you may start with one operator, it is assumed that ultimately multiple operators will be managed together in one catalog.

Open the operator catalog template repository and create a repository for the operator catalog using the template
Copy the repository url
Create/connect to the project for the operator development. This does not need to be the same one used for the operator build.
```
oc sync ${OPERATOR_NAMESPACE}
```

oc pipeline --tekton ${GIT_URL}

Register the catalog repository with the operator pipeline

The last step of the operator pipeline will update the operator catalog repository with the new version of the operator bundle that was created. This update will trigger the creation of a new version of the catalog.

Change to the project where the operator pipeline was registered

oc project ${OPERATOR_NAMESPACE}

Change the directory to the local clone of your operator catalog repository

igc git-secret olm-catalog-repo

Kick off the operator pipeline again to update the operator catalog repo

Configure the GitOps repo

If you don’t already have one, create a GitOps repo from the gitops template template

Clone the GitOps repo to the local machine

git clone ${GIT_URL}

Change the directory to the cloned GitOps repo

Change to the project where the operator catalog pipeline was registered

oc project ${OPERATOR_NAMESPACE}

oc gitops

Trigger the operator catalog pipeline build to register the catalog source in the GitOps repo
Configure ArgoCD to deploy the CatalogSource into the namespace openshift-marketplace

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