How to setup terraform CI in github (#60)

* How to setup terraform CI in github

Author: Edvin N

docs/xks/operator-guide/github.md

@@ -0,0 +1,108 @@
+---
+id: github
+title: XKF on Github
+---
+
+As a XKF user you can use both Azure DevOps and GitHub to store
+your terraform and gitops repositories.
+
+In this document we will go through how to use XKF on GitHub focusing
+on Infrastructure As Code (IAC) using Terraform.
+
+## Terraform
+
+How to run Terraform plan and apply through a GitHub action workflow.
+
+### Workflow
+
+Just like in azure devops case we have created a
+[basic pipeline](https://github.com/XenitAB/azure-devops-templates/terraform-docker-github/README.md)
+for easy use.
+
+Below you can find a example pipeline that uses the github action workflow.
+Read further down to see how to create the secrets needed to run the pipeline.
+
+You should store this GitHub action in your Terraform repository under `.github/workflows/name.yaml`
+
+```.github/workflows/core.yaml
+name: terraform_core
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - core/**
+  pull_request:
+    paths:
+      - core/**
+  workflow_dispatch:
+    inputs:
+      OPA_BLAST_RADIUS:
+        description: OPA Blast Radius
+        required: true
+        default: "50"
+
+jobs:
+  terraform:
+    uses: xenitab/azure-devops-templates/.github/workflows/terraform-docker.yaml@2021.10.1
+    with:
+      DIR: core
+      runs-on: '["self-hosted", "linux"]' # If you don't want to use the default ubuntu-latest
+      ENVIRONMENTS: |
+        {
+          "environments":[
+            {"name":"dev"},
+            {"name":"qa"},
+            {"name":"prod"}
+          ]
+        }
+    secrets:
+      AZURE_CREDENTIALS_DEV: ${{ secrets.AZURE_CREDENTIALS_DEV }}
+      AZURE_CREDENTIALS_QA: ${{ secrets.AZURE_CREDENTIALS_QA }}
+      AZURE_CREDENTIALS_PROD: ${{ secrets.AZURE_CREDENTIALS_PROD }}
+```
+
+### Azure Service Principal
+
+Create a Service Principal(SP) with the access that terraform requires to perform all the tasks you want.
+You can read more about SP creation in our [operator guide](operator-guide.md)
+
+The workflow is using [Azure Login GitHub Action](https://github.com/marketplace/actions/azure-login#configure-deployment-credentials)
+to login to Azure. When uploading your SP to GitHub make sure to follow the formatting in the examples.
+
+This is to prevent unnecessary masking of { } in your logs which are in dictionary form.
+
+**For example, do**:
+
+```.json
+{"clientId": "00000000-0000-0000-0000-000000000000",
+  "clientSecret": "super-duper-secret-value",
+  "subscriptionId": "00000000-0000-0000-0000-000000000000",
+  "tenantId": "00000000-0000-0000-0000-000000000000"}
+```
+
+**instead of**:
+
+```.json
+{
+  "clientId": "00000000-0000-0000-0000-000000000000",
+  "clientSecret": "super-duper-secret-value",
+  "subscriptionId": "00000000-0000-0000-0000-000000000000",
+  "tenantId": "00000000-0000-0000-0000-000000000000"
+}
+```
+
+Upload the entire json as your github secret.
+The workflow uses one secret per environment and we recommend that you follow our namestandard.
+The secret name the workflow use is **AZURE_CREDENTIALS_\<ENV\>**, for  example **AZURE_CREDENTIALS_DEV**
+
+To upload the secret to github you can use the github UI or you can use the [gh cli](https://github.com/cli/cli) to upload secrets to GitHub.
+
+Assuming that you are storing the SP json data in a file you could do:
+
+```shell
+gh secret -R ORG/xks-terraform set AZURE_CREDENTIALS_DEV < dev-secrets.json
+gh secret -R ORG/xks-terraform set AZURE_CREDENTIALS_QA < qa-secrets.json
+gh secret -R ORG/xks-terraform set AZURE_CREDENTIALS_PROD < prod-secrets.json
+```

sidebars.js

@@ -38,7 +38,8 @@ module.exports = {
             "xks/operator-guide/eks",
             "xks/operator-guide/blast-radius",
             "xks/operator-guide/operator-guide",
-            "xks/operator-guide/azure-devops-agents"
+            "xks/operator-guide/azure-devops-agents",
+            "xks/operator-guide/github",
           ]
         }
       ]