Set up GitOps Repository for Flux

Flux watches a Git repository containing the resource manifests that should be deployed into the Kubernetes cluster, and, as such, we need to configure that repo and give Flux permissions to access it at cluster creation time.

1. Create a repo to use for GitOps. This example will assume that you are using one of the public git repo such as GitHub, Azure DevOps, GitLab, or BitBucket, but flux supports private git repos with additional configuration.
2. Create/choose a SSH key pair that will be given permission to do read/write access to the repository. You can create an ssh key pair with the Bash ssh-keygen command as shown in the code block below. Do not enter a passphrase, as Flux will be unable to sign with a passphrase protected private key.
3. Add the SSH public key to the repository. Flux requires read and write access to the resource manifest git repository. For GitHub, the process to add a deploy key is documented here. For Azure DevOps repos, the process is documented here.
4. Have your CI/CD pipeline run at least once and commit an initial set of resource manifests to your repo. Flux requires at least one commit in your resource manifest repo to operate correctly.

$ ssh-keygen -b 2048 -t rsa -f gitops_repo_key
Generating public/private rsa key pair.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in gitops_repo_key.
Your public key has been saved in gitops_repo_key.pub.
The key fingerprint is:
SHA256:DgAbaIRrET0rM/U5PIT0mcBFVMW/AQ9sRJ/TsdcmmFA
The key's randomart image is:
+---[RSA 2048]----+
|o+Bo=+..*+..E.   |
|oo Xo.o  *..ooo .|
|..+ B+. . =+oo..o|
|.= . B     +. .o |
|. +   + S   o    |
|       o   .     |
|        .        |
|                 |
|                 |
+----[SHA256]-----+
$ ls -l gitops_repo_key*
-rw-------  1 jims  staff  1823 Jan 24 16:28 gitops_repo_key
-rw-r--r--  1 jims  staff   398 Jan 24 16:28 gitops_repo_key.pub