Terraform Configuration Drift Detection #693
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name: 'Terraform Configuration Drift Detection' | |
on: | |
workflow_dispatch: | |
schedule: | |
- cron: '41 3 * * *' # runs nightly at 3:41 am | |
#Special permissions required for OIDC authentication | |
permissions: | |
id-token: write | |
contents: read | |
issues: write | |
#These environment variables are used by the terraform azure provider to setup OIDD authenticate. | |
env: | |
ARM_CLIENT_ID: "${{ secrets.AZURE_CLIENT_ID }}" | |
ARM_SUBSCRIPTION_ID: "${{ secrets.AZURE_SUBSCRIPTION_ID }}" | |
ARM_TENANT_ID: "${{ secrets.AZURE_TENANT_ID }}" | |
jobs: | |
terraform-plan: | |
name: 'Terraform Plan' | |
runs-on: ubuntu-latest | |
env: | |
#this is needed since we are running terraform with read-only permissions | |
ARM_SKIP_PROVIDER_REGISTRATION: true | |
outputs: | |
tfplanExitCode: ${{ steps.tf-plan.outputs.exitcode }} | |
steps: | |
# Checkout the repository to the GitHub Actions runner | |
- name: Checkout | |
uses: actions/checkout@v4 | |
# Install the latest version of the Terraform CLI | |
- name: Setup Terraform | |
uses: hashicorp/setup-terraform@v3 | |
with: | |
terraform_wrapper: false | |
# Initialize a new or existing Terraform working directory by creating initial files, loading any remote state, downloading modules, etc. | |
- name: Terraform Init | |
run: terraform init | |
# Generates an execution plan for Terraform | |
# An exit code of 0 indicated no changes, 1 a terraform failure, 2 there are pending changes. | |
- name: Terraform Plan | |
id: tf-plan | |
run: | | |
export exitcode=0 | |
terraform plan -detailed-exitcode -no-color -out tfplan || export exitcode=$? | |
echo "exitcode=$exitcode" >> $GITHUB_OUTPUT | |
if [ $exitcode -eq 1 ]; then | |
echo Terraform Plan Failed! | |
exit 1 | |
else | |
exit 0 | |
fi | |
# Save plan to artifacts | |
- name: Publish Terraform Plan | |
uses: actions/upload-artifact@v4 | |
with: | |
name: tfplan | |
path: tfplan | |
# Create string output of Terraform Plan | |
- name: Create String Output | |
id: tf-plan-string | |
run: | | |
TERRAFORM_PLAN=$(terraform show -no-color tfplan) | |
delimiter="$(openssl rand -hex 8)" | |
echo "summary<<${delimiter}" >> $GITHUB_OUTPUT | |
echo "## Terraform Plan Output" >> $GITHUB_OUTPUT | |
echo "<details><summary>Click to expand</summary>" >> $GITHUB_OUTPUT | |
echo "" >> $GITHUB_OUTPUT | |
echo '```terraform' >> $GITHUB_OUTPUT | |
echo "$TERRAFORM_PLAN" >> $GITHUB_OUTPUT | |
echo '```' >> $GITHUB_OUTPUT | |
echo "</details>" >> $GITHUB_OUTPUT | |
echo "${delimiter}" >> $GITHUB_OUTPUT | |
# Publish Terraform Plan as task summary | |
- name: Publish Terraform Plan to Task Summary | |
env: | |
SUMMARY: ${{ steps.tf-plan-string.outputs.summary }} | |
run: | | |
echo "$SUMMARY" >> $GITHUB_STEP_SUMMARY | |
# If changes are detected, create a new issue | |
- name: Publish Drift Report | |
if: steps.tf-plan.outputs.exitcode == 2 | |
uses: actions/github-script@v7 | |
env: | |
SUMMARY: "${{ steps.tf-plan-string.outputs.summary }}" | |
with: | |
github-token: ${{ secrets.GITHUB_TOKEN }} | |
script: | | |
const body = `${process.env.SUMMARY}`; | |
const title = 'Terraform Configuration Drift Detected'; | |
const creator = 'github-actions[bot]' | |
// Look to see if there is an existing drift issue | |
const issues = await github.rest.issues.listForRepo({ | |
owner: context.repo.owner, | |
repo: context.repo.repo, | |
state: 'open', | |
creator: creator, | |
title: title | |
}) | |
if( issues.data.length > 0 ) { | |
// We assume there shouldn't be more than 1 open issue, since we update any issue we find | |
const issue = issues.data[0] | |
if ( issue.body == body ) { | |
console.log('Drift Detected: Found matching issue with duplicate content') | |
} else { | |
console.log('Drift Detected: Found matching issue, updating body') | |
github.rest.issues.update({ | |
owner: context.repo.owner, | |
repo: context.repo.repo, | |
issue_number: issue.number, | |
body: body | |
}) | |
} | |
} else { | |
console.log('Drift Detected: Creating new issue') | |
github.rest.issues.create({ | |
owner: context.repo.owner, | |
repo: context.repo.repo, | |
title: title, | |
body: body | |
}) | |
} | |
# If changes aren't detected, close any open drift issues | |
- name: Publish Drift Report | |
if: steps.tf-plan.outputs.exitcode == 0 | |
uses: actions/github-script@v7 | |
with: | |
github-token: ${{ secrets.GITHUB_TOKEN }} | |
script: | | |
const title = 'Terraform Configuration Drift Detected'; | |
const creator = 'github-actions[bot]' | |
// Look to see if there is an existing drift issue | |
const issues = await github.rest.issues.listForRepo({ | |
owner: context.repo.owner, | |
repo: context.repo.repo, | |
state: 'open', | |
creator: creator, | |
title: title | |
}) | |
if( issues.data.length > 0 ) { | |
const issue = issues.data[0] | |
github.rest.issues.update({ | |
owner: context.repo.owner, | |
repo: context.repo.repo, | |
issue_number: issue.number, | |
state: 'closed' | |
}) | |
} | |
# Mark the workflow as failed if drift detected | |
- name: Error on Failure | |
if: steps.tf-plan.outputs.exitcode == 2 | |
run: exit 1 |