feat: add custom aws-cli Helm chart (#3)

Deploy a custom AWS CLI application via Helm on Kubernetes. This custom application uses IRSA thanks to the EKS annotation set on the ServiceAccount.
Add steps in linter workflow to lint aws-cli Helm chart and deactivate lint of YAML files with super linter.
Update README.md to explain how to deploy the custom Helm chart onto Kubernetes.

.github/workflows/linter.yml

@@ -18,9 +18,19 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Lint Code Base
+      - name: Lint with super linter
         uses: github/super-linter/slim@v4
         env:
           VALIDATE_ALL_CODEBASE: false
           DEFAULT_BRANCH: main
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          VALIDATE_KUBERNETES_KUBEVAL: false
+          VALIDATE_YAML: false
+
+      - name: Setup Helm
+        uses: azure/setup-helm@v3
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Helm lint aws-cli chart
+        run: helm lint --set awsAccountId=123456789123 helm/aws-cli

README.md

@@ -11,6 +11,7 @@ You need several tools to be able to interact with the infrastructure of this pr
 - Terragrunt
 - aws CLI v2
 - kubectl
+- helm v3
 
 You can install those tools on your computer thanks to [tfswitch](https://github.com/warrensbox/terraform-switcher) and
 to [tgswitch](https://github.com/warrensbox/tgswitch).
@@ -53,3 +54,23 @@ Then, you can interact with the Kubernetes cluster with `kubectl` commands:
 ```bash
 kubectl get pods -n kube-system
 ```
+
+## How to deploy aws-cli Helm chart?
+
+You can install the `aws-cli` Helm chart as such (after replacing `<YOUR_AWS_ACCOUNT_ID>` with your account ID):
+```bash
+helm install --create-namespace --namespace aws-eks-irsa --set awsAccountId=<YOUR_AWS_ACCOUNT_ID> aws-cli helm/aws-cli
+```
+
+Then, you can check your resources were created into the EKS cluster:
+```bash
+kubectl get all -n aws-eks-irsa
+```
+
+When the `aws-cli` pod is running, connect to it and execute an AWS CLI command as such:
+```bash
+# Exec into the pod
+kubectl exec -n aws-eks-irsa -it $(kubectl get pods -n aws-eks-irsa -o=name) -- bash
+# Once inside the aws-cli pod, try to describe EC2 instances ;)
+aws ec2 describe-instances --filters Name=tag:aws:eks:cluster-name,Values=aws-eks-irsa
+```

helm/aws-cli/.helmignore

@@ -0,0 +1,23 @@
+# Patterns to ignore when building packages.
+# This supports shell glob matching, relative path matching, and
+# negation (prefixed with !). Only one pattern per line.
+.DS_Store
+# Common VCS dirs
+.git/
+.gitignore
+.bzr/
+.bzrignore
+.hg/
+.hgignore
+.svn/
+# Common backup files
+*.swp
+*.bak
+*.tmp
+*.orig
+*~
+# Various IDEs
+.project
+.idea/
+*.tmproj
+.vscode/

helm/aws-cli/Chart.yaml

@@ -0,0 +1,25 @@
+---
+apiVersion: v2
+name: aws-cli
+description: A Helm chart for Kubernetes
+
+# A chart can be either an 'application' or a 'library' chart.
+#
+# Application charts are a collection of templates that can be packaged into versioned archives
+# to be deployed.
+#
+# Library charts provide useful utilities or functions for the chart developer. They're included as
+# a dependency of application charts to inject those utilities and functions into the rendering
+# pipeline. Library charts do not define any templates and therefore cannot be deployed.
+type: application
+
+# This is the chart version. This version number should be incremented each time you make changes
+# to the chart and its templates, including the app version.
+# Versions are expected to follow Semantic Versioning (https://semver.org/)
+version: 0.1.0
+
+# This is the version number of the application being deployed. This version number should be
+# incremented each time you make changes to the application. Versions are not expected to
+# follow Semantic Versioning. They should reflect the version the application is using.
+# It is recommended to use it with quotes.
+appVersion: "1.16.0"

helm/aws-cli/templates/_helpers.tpl

@@ -0,0 +1,62 @@
+{{/*
+Expand the name of the chart.
+*/}}
+{{- define "aws-cli.name" -}}
+{{- default .Chart.Name .Values.nameOverride | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Create a default fully qualified app name.
+We truncate at 63 chars because some Kubernetes name fields are limited to this (by the DNS naming spec).
+If release name contains chart name it will be used as a full name.
+*/}}
+{{- define "aws-cli.fullname" -}}
+{{- if .Values.fullnameOverride }}
+{{- .Values.fullnameOverride | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- $name := default .Chart.Name .Values.nameOverride }}
+{{- if contains $name .Release.Name }}
+{{- .Release.Name | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- printf "%s-%s" .Release.Name $name | trunc 63 | trimSuffix "-" }}
+{{- end }}
+{{- end }}
+{{- end }}
+
+{{/*
+Create chart name and version as used by the chart label.
+*/}}
+{{- define "aws-cli.chart" -}}
+{{- printf "%s-%s" .Chart.Name .Chart.Version | replace "+" "_" | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Common labels
+*/}}
+{{- define "aws-cli.labels" -}}
+helm.sh/chart: {{ include "aws-cli.chart" . }}
+{{ include "aws-cli.selectorLabels" . }}
+{{- if .Chart.AppVersion }}
+app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
+{{- end }}
+app.kubernetes.io/managed-by: {{ .Release.Service }}
+{{- end }}
+
+{{/*
+Selector labels
+*/}}
+{{- define "aws-cli.selectorLabels" -}}
+app.kubernetes.io/name: {{ include "aws-cli.name" . }}
+app.kubernetes.io/instance: {{ .Release.Name }}
+{{- end }}
+
+{{/*
+Create the name of the service account to use
+*/}}
+{{- define "aws-cli.serviceAccountName" -}}
+{{- if .Values.serviceAccount.create }}
+{{- default (include "aws-cli.fullname" .) .Values.serviceAccount.name }}
+{{- else }}
+{{- default "default" .Values.serviceAccount.name }}
+{{- end }}
+{{- end }}

helm/aws-cli/templates/deployment.yaml

@@ -0,0 +1,52 @@
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ include "aws-cli.fullname" . }}
+  labels:
+    {{- include "aws-cli.labels" . | nindent 4 }}
+spec:
+  replicas: {{ .Values.replicaCount }}
+  selector:
+    matchLabels:
+      {{- include "aws-cli.selectorLabels" . | nindent 6 }}
+  template:
+    metadata:
+      {{- with .Values.podAnnotations }}
+      annotations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      labels:
+        {{- include "aws-cli.selectorLabels" . | nindent 8 }}
+    spec:
+      {{- with .Values.imagePullSecrets }}
+      imagePullSecrets:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      serviceAccountName: {{ include "aws-cli.serviceAccountName" . }}
+      securityContext:
+        {{- toYaml .Values.podSecurityContext | nindent 8 }}
+      containers:
+        - name: {{ .Chart.Name }}
+          securityContext:
+            {{- toYaml .Values.securityContext | nindent 12 }}
+          image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
+          imagePullPolicy: {{ .Values.image.pullPolicy }}
+          command:
+            - "sh"
+            - "-c"
+            - "tail -f /dev/null"
+          resources:
+            {{- toYaml .Values.resources | nindent 12 }}
+      {{- with .Values.nodeSelector }}
+      nodeSelector:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.affinity }}
+      affinity:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.tolerations }}
+      tolerations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}

helm/aws-cli/templates/serviceaccount.yaml

@@ -0,0 +1,13 @@
+{{- if .Values.serviceAccount.create -}}
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: {{ include "aws-cli.serviceAccountName" . }}
+  labels:
+    {{- include "aws-cli.labels" . | nindent 4 }}
+  annotations:
+    eks.amazonaws.com/role-arn: arn:aws:iam::{{ .Values.awsAccountId }}:role/irsa/aws-cli-describe-ec2-instances
+    {{- with .Values.serviceAccount.annotations }}
+    {{- toYaml . | nindent 4 }}
+    {{- end }}
+{{- end }}

helm/aws-cli/values.yaml

@@ -0,0 +1,56 @@
+# Default values for aws-cli.
+# This is a YAML-formatted file.
+# Declare variables to be passed into your templates.
+
+awsAccountId:
+
+replicaCount: 1
+
+image:
+  repository: amazon/aws-cli
+  pullPolicy: IfNotPresent
+  tag: "2.9.0"
+
+imagePullSecrets: []
+nameOverride: ""
+fullnameOverride: ""
+
+serviceAccount:
+  # Specifies whether a service account should be created
+  create: true
+  # Annotations to add to the service account
+  annotations: {}
+  # The name of the service account to use.
+  # If not set and create is true, a name is generated using the fullname template
+  name: ""
+
+podAnnotations: {}
+
+podSecurityContext: {}
+  # fsGroup: 2000
+
+securityContext: {}
+  # capabilities:
+  #   drop:
+  #   - ALL
+  # readOnlyRootFilesystem: true
+  # runAsNonRoot: true
+  # runAsUser: 1000
+
+resources: {}
+  # We usually recommend not to specify default resources and to leave this as a conscious
+  # choice for the user. This also increases chances charts run on environments with little
+  # resources, such as Minikube. If you do want to specify resources, uncomment the following
+  # lines, adjust them as necessary, and remove the curly braces after 'resources:'.
+  # limits:
+  #   cpu: 100m
+  #   memory: 128Mi
+  # requests:
+  #   cpu: 100m
+  #   memory: 128Mi
+
+nodeSelector: {}
+
+tolerations: []
+
+affinity: {}