CD for Inventory Micro App

Extending the Inventory Micro app to include Continuous Delivery to Test.

Guide

This Micro App guidance continues to build upon the microserivces that were built in the Inventory Micro App guide. Make sure you have complete Inventory App or deployed the working Inventory Solution.

we implemented the three tiers in the Inventory Mico App and deployed the app to the dev namespace/project.
We will take that app and make these additions.
Deploy the app to the test namespace/project using CD techniques and ArgoCD

Using CD to deploy to Test

ArgoCD is a tool that provides continuous delivery for projects and applications. If you haven’t already, be sure to read through the Continuous Delivery with ArgoCD guide.

For this exercise, we are going to use ArgoCD to push the Inventory app from dev to test (and possibly staging as well). If you have already completed the Inventory Micro App , then it can be used for the ArgoCD process (although perhaps with some minor pipeline updates). If you haven’t completed the exercise, you can start from the solution repositories to perform the ArgoCD steps.

Set up the GitOps repo

Let’s get started with using Argo CD.

Create a new repo from the ArgoCD Code Pattern
Clone the project to your machine

Create a branch named test

git checkout -b test

Push the branch to the remote

git push -u origin test

Create the test namespace with the CLI by running oc sync test-{initials} --dev

Register the GitOps repo in ArgoCD

Now that the repository has been created, we need to tell ArgoCD where it is.

Get the ArgoCD login information from the oc credentials cli command
Note: You need to be logged into the cluster on the command-line for the CLI to access the cluster information.
Log into ArgoCD (use oc credentials to obtain your credentials and login to argo)
Click on the gear icon on the left menu to access the Settings options
Select the Repositories option
Click either the Connect Repo using HTTPS or Connect Repo using SSH button at the top and provide the information for the GitOps repo you just created.

Create a project in ArgoCD (Optional)

In ArgoCD terms, each deployable component is an Application and applications are grouped into Projects. Projects are not required for ArgoCD to be able to deploy applications but it helps to organize applications and provide some restrictions on what can be done for applications that make up a project.

To create a project, do the following:

Log into ArgoCD
Click on the gear icon on the left menu to access the Settings options
Select the Projects option
Click the New Project button at the top of the page.

Provide the following values then press Create:

name - the name for the project (provide `inventory-management)
description - a brief description of the project
sources - click add source and pick the Git repository from the list that was added previously

destinations

- Add `https://kubernetes.default.svc` for the cluster url and `test-{initials}` for the namespace
- Add `https://kubernetes.default.svc` for the cluster url and `staging-{initials}` for the namespace

Note: Initially, the only cluster that is available is the one in which ArgoCD is - https://kubernetes.default.svc. By adding the two destinations we have allowed the project to be deployed to both the test-{initials} and staging-{initials} namespaces within the current cluster.

Configure the GitOps repo for Inventory Management service

Copy the app-artifactory folder and give it a name that matches the Inventory Management service component (e.g. inventory-management-svc-{initials})
Update inventory-management-svc-{initials}/Chart.yaml and update the name to match the directory name
Update inventory-management-svc-{initials}/requirements.yaml with the following values:
- name - the name of helm chart/image. This should match the folder name
- version - the version number of the helm chart
- repository - the url to the helm repository including the folder where helm charts are being stored.

here is an example

dependencies:
- name: inventory-management-svc-mjp
  version: 1.0.0-1
  repository: http://artifactory.mooc-one-rhos-cluster.us-east.containers.appdomain.cloud/artifactory/generic-local/mooc-team-one/

The url of the Artifactory helm repository can be determines by following these steps:

Log into Artifactory (use igc credentials to obtain your credentials and login to artifactory console).Go to the Artifactory tab and select “Artifacts”.
Click on Set Me Up.
In the Set Me Up Section, select the tool as “Generic” and repository as “generic-local”.Copy the deploy URL from the Set Me Up dialog box. That is the Artifactory helm repository URL.

Run kubectl get configmap/ibmcloud-config -n tools -o yaml to print the configuration information for the cluster

In inventory-management-svc-{initials}/values.yaml replace <app-chart-name> with the directory name. Replace ingressSubdomain with the value from the previous step. Update tlsSecretName with the value from the previous step. The result should look something like the following

inventory-management-svc-{initials}/values.yaml
global:
  ingressSubdomain: sms-test.us-south.containers.appdomain.cloud
  tlsSecretName: sms-test-cluster
inventory-management-svc-{initials}:
  replicaCount: 1
  ingress:
    enabled: true

Commit and push the changes

git add .
git commit -m "Adds inventory-management-svc config"
git push

Add an application in ArgoCD for the Inventory Management service

The last step in the process is to define the application(s) within ArgoCD that should be managed. This consists of connecting the config within the Git repo to the cluster and namespace.

Log into ArgoCD
Click New Application and provide the following values:
- application name - test-inventory-management-svc
- project - inventory-management
- sync-policy - Automatic
- repository url - The Git url where the configuration is stored
- revision - test
- path - inventory-management-svc-{initials}
- destination cluster - The cluster url for the deployment
- destination namespace - test-{initials}
- values file - values.yaml
Click Create
Click on the newly created application. A graph of kubernetes resources should be shown if everything is configured correctly.

Make a change in the GitOps repo

In order to trigger a (re-)deployment we can make an update to a value in the GitOps repo and watch ArgoCD apply the change.

Open a terminal and navigate to your GitOps repo directory

Be sure that you are in the test branch

git checkout test

Update inventory-management-svc-{initials}/values.yaml to increase the replica count

inventory-management-svc-{initials}/values.yaml
global:
  ingressSubdomain: sms-test.us-south.containers.appdomain.cloud
  tlsSecretName: sms-test-cluster
inventory-management-svc-{initials}:
  replicaCount: 3
  ingress:
    enabled: true

Commit and push the change

git add .
git commit -m "Increases replica count"

Log into the ArgoCD UI and look at the state of the application. It should say Synchronizing. If you don’t want to wait you can manually by pressing the Synchronize button.

Hook the CI pipeline to the CD pipeline

The last stage in the CI pipeline updates the version number in the requirements.yaml to the version of the helm chart that was just built. Through a couple naming conventions the only thing the pipeline needs in order to interact with the CD process is a kubernetes secret named gitops-cd-secret that provides the details needed to connect to the git repo to push updates.

The IGC CLI has a command that provides a helper to make the creating of a kubernetes secret with git credentials very easy.

Log into the cluster on the command-line.
Change the directory to the root of the ArgoCD Code Pattern repo that was cloned previously.
Run igc git-secret gitops-repo -n dev-{initials} to create the secret. This command will prompt for the username, personal access token, and the branch to put in the secret.

What just happened?

The git-secret command creates a secret in a kubernetes namespace containing the url, username, password, and branch information for a git repo. In the command above, we provided gitops-cd-secret for the secret name. (If that value is left off the secret name defaults to {git org}.{git repo}.). It creates a secret “git-credentials” and configmap “gitops-cd-secret” You can verify the secret was created by running:
```
kubectl get configmap/gitops-cd-secret -n dev-{initials} -o yaml
```

Note:

For the secret to be available to the CI pipeline, the secret needs to be created in the same namespace where the pipeline is running (e.g. dev-{initials}).
The value provided for branch is the one the pipeline will use to when committing changes to trigger the CD pipeline. test is the recommended value for the branch field.
Trigger the pipeline for the Inventory Management service to build by making a change to the Inventory Management Service code and push the changes to Git.

Repeat for BFF and UI components

Starting from Configure the GitOps repo for Inventory Management service, the steps need to be repeated for each application within the project.

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