castai-ci-integration

# CAST AI CI Integration

## Overview

Add CAST AI cost validation to CI/CD pipelines: verify savings thresholds, validate Terraform plans before apply, and gate deployments on autoscaler health.

## Prerequisites

- GitHub Actions enabled
- CAST AI API key stored as repository secret
- Terraform state accessible from CI (if using Terraform)

## Instructions

### Step 1: GitHub Actions -- Savings Gate

```yaml
# .github/workflows/castai-check.yml
name: CAST AI Cost Check

on:
  pull_request:
    paths: ["terraform/**", "k8s/**"]
  schedule:
    - cron: "0 8 * * 1"  # Weekly Monday report

jobs:
  cost-check:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Check CAST AI Savings
        env:
          CASTAI_API_KEY: ${{ secrets.CASTAI_API_KEY }}
          CASTAI_CLUSTER_ID: ${{ secrets.CASTAI_CLUSTER_ID }}
        run: |
          SAVINGS=$(curl -s -H "X-API-Key: ${CASTAI_API_KEY}" \
            "https://api.cast.ai/v1/kubernetes/clusters/${CASTAI_CLUSTER_ID}/savings")

          PERCENT=$(echo "$SAVINGS" | jq -r '.savingsPercentage')
          MONTHLY=$(echo "$SAVINGS" | jq -r '.monthlySavings')

          echo "### CAST AI Savings Report" >> $GITHUB_STEP_SUMMARY
          echo "- Monthly savings: \$${MONTHLY}" >> $GITHUB_STEP_SUMMARY
          echo "- Savings percentage: ${PERCENT}%" >> $GITHUB_STEP_SUMMARY

          # Fail if savings drop below threshold
          if (( $(echo "$PERCENT < 10" | bc -l) )); then
            echo "WARNING: Savings below 10% threshold"
            exit 1
          fi

      - name: Verify Agent Health
        env:
          CASTAI_API_KEY: ${{ secrets.CASTAI_API_KEY }}
          CASTAI_CLUSTER_ID: ${{ secrets.CASTAI_CLUSTER_ID }}
        run: |
          STATUS=$(curl -s -H "X-API-Key: ${CASTAI_API_KEY}" \
            "https://api.cast.ai/v1/kubernetes/external-clusters/${CASTAI_CLUSTER_ID}" \
            | jq -r '.agentStatus')

          if [ "$STATUS" != "online" ]; then
            echo "CAST AI agent is ${STATUS}, expected online"
            exit 1
          fi
```

### Step 2: Terraform Plan Validation

```yaml
  terraform-plan:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: hashicorp/setup-terraform@v3

      - name: Terraform Init & Plan
        working-directory: terraform/
        env:
          CASTAI_API_TOKEN: ${{ secrets.CASTAI_API_KEY }}
        run: |
          terraform init
          terraform plan -var-file=environments/prod.tfvars \
            -out=plan.tfplan -no-color | tee plan-output.txt

      - name: Check for Destructive Changes
        run: |
          if grep -q "will be destroyed" terraform/plan-output.txt; then
            echo "DESTRUCTIVE CHANGES DETECTED in CAST AI resources"
            exit 1
          fi
```

### Step 3: Store Secrets

```bash
gh secret set CASTAI_API_KEY --body "your-api-key"
gh secret set CASTAI_CLUSTER_ID --body "your-cluster-id"
```

## Error Handling

| Issue | Cause | Solution |
|-------|-------|----------|
| Secret not found | Missing `gh secret set` | Add secrets to repo |
| Savings check fails | Cluster not onboarded | Verify cluster ID is correct |
| Terraform init fails | State backend misconfigured | Check backend config |
| Agent offline in CI | Key scope mismatch | Use production API key |

## Resources

- [GitHub Actions Secrets](https://docs.github.com/en/actions/security-guides/encrypted-secrets)
- [CAST AI API Reference](https://api.cast.ai/v1/spec/openapi.json)

## Next Steps

For deployment patterns, see `castai-deploy-integration`.