Argocd

gitops repo structure

clusters
    {cluster_name}
        system 
        ops
        game
        etc.
shared
    system
        istio
        cert-manager
    ops
        nginx
            nginx-header_helm.yaml
    game
    etc.

clusters/{cluster_name}/system contains the system components that are not shared. For example argocd only exists on the argocd cluster gha-controller only exists on the ci cluster etc.

shared/system/ contains applicationSets, those resources generate Application for every cluster according to some parameters (cluster/git files/list/more complex if we want to). It doesn't have to be on all clusters, but if it's more than 1 it's useful to have an applicationSet for it. These are the things we always install and have very little variation between clusters. For example istio, cert-manager, etc. We should aim to have as much as possible here.

shared/ops/nginx/nginx_helm.yaml is an applicationSet that takes a remote helm chart and installs it in a list of cluster. values can be templated directly in the applicationSet. This design while being the most straightforward does not allow to permanently override values for a given cluster. It's good for things that have very little variation between clusters.

shared/ops/nginx/nginx_helm_umbrella.yaml is an applicationSet that looks for a helm chart in clusters/{cluster_name}/ops/nginx This folders contains:

A Chart.yaml file with a dependency to a chart that installs nginx-header
A values.yaml file that has values specific to the cluster

terraform

create cluster
create cluster dependencies
- acm
- iam role
install argo via helm provider
install alb ingress
bootstrap argo
- create an argo application that looks at the clusters/argo folder in gitops
- clusters/argo folder contains bootstrap.yaml <- from now on we manage argo via argo
- clusters/argo/system/argocd contains all argocd required config
- clusters/argo/root.yaml creates an application that looks at shared/
- shared/system/istio contains everything to bootstrap istio on any cluster

kuuji/gitops

Argocd

gitops repo structure