README.md

Multi-project

These examples show how to run Infracost actions against a multi-project setup using either an Infracost config file or a GitHub Actions build matrix.

Using an Infracost config file

This example shows how to run Infracost actions with multiple Terraform projects using an Infracost config file.

name: Multi-project config file
on: [pull_request]

jobs:
  multi-project-config-file:
    name: Multi-project config file
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2
      
      - name: Install Terraform
        uses: hashicorp/setup-terraform@v1
        with:
          terraform_wrapper: false # This is recommended so the `terraform show` command outputs valid JSON

      - name: Setup Infracost
        uses: infracost/actions/setup@v1
        with:
          api-key: ${{ secrets.INFRACOST_API_KEY }}

      - name: Run Infracost
        run: infracost breakdown --config-file=examples/multi-project/code/infracost.yml --format=json --out-file=/tmp/infracost.json
        env:
          # IMPORTANT: add any required secrets to setup cloud credentials so Terraform can run
          DEV_AWS_ACCESS_KEY_ID: ${{ secrets.EXAMPLE_DEV_AWS_ACCESS_KEY_ID }}
          DEV_AWS_SECRET_ACCESS_KEY: ${{ secrets.EXAMPLE_DEV_AWS_SECRET_ACCESS_KEY }}
          PROD_AWS_ACCESS_KEY_ID: ${{ secrets.EXAMPLE_PROD_AWS_ACCESS_KEY_ID }}
          PROD_AWS_SECRET_ACCESS_KEY: ${{ secrets.EXAMPLE_PROD_AWS_SECRET_ACCESS_KEY }}

      - name: Post the comment
        uses: infracost/actions/comment@v1
        with:
          path: /tmp/infracost.json
          behavior: update # Create a single comment and update it. See https://github.com/infracost/actions/tree/master/comment for other options

Using GitHub Actions build matrix

This example shows how to run Infracost actions with multiple Terraform projects using a GitHub Actions build matrix. The first job uses a build matrix to generate multiple Infracost output JSON files and upload them as artifacts. The second job downloads these JSON files, combines them using infracost output, and posts a comment.

name: Multi-project matrix
on: [pull_request]

jobs:
  multi-project-matrix:
    name: Multi-project matrix
    runs-on: ubuntu-latest

    strategy:
      matrix:
        include:
          # IMPORTANT: add any required secrets to setup cloud credentials so Terraform can run
          - dir: dev
            # GitHub actions doesn't support secrets in matrix values, so we use the name of the secret instead
            aws_access_key_id_secret: EXAMPLE_DEV_AWS_ACCESS_KEY_ID 
            aws_secret_access_key_secret: EXAMPLE_DEV_AWS_SECRET_ACCESS_KEY
          - dir: prod
            aws_access_key_id_secret: EXAMPLE_PROD_AWS_ACCESS_KEY_ID
            aws_secret_access_key_secret: EXAMPLE_PROD_AWS_SECRET_ACCESS_KEY

    steps:
      - uses: actions/checkout@v2
      
      - name: Install Terraform
        uses: hashicorp/setup-terraform@v1
        with:
          terraform_wrapper: false # This is recommended so the `terraform show` command outputs valid JSON

      - name: Setup Infracost
        uses: infracost/actions/setup@v1
        with:
          api-key: ${{ secrets.INFRACOST_API_KEY }}
          
      - name: Run Infracost
        run: infracost breakdown --path=examples/multi-project/code/${{ matrix.dir }} --format=json --out-file=/tmp/infracost_${{ matrix.dir }}.json
        env:
          AWS_ACCESS_KEY_ID: ${{ secrets[matrix.aws_access_key_id_secret] }}
          AWS_SECRET_ACCESS_KEY: ${{ secrets[matrix.aws_secret_access_key_secret] }}
        
      - name: Upload Infracost breakdown
        uses: actions/upload-artifact@v2
        with:
          name: infracost_jsons
          path: /tmp/infracost_${{ matrix.dir }}.json

  multi-project-matrix-merge:
    name: Multi-project matrix merge
    runs-on: ubuntu-latest
    needs: [multi-project-matrix]

    steps:
      - uses: actions/checkout@v2

      - name: Download all Infracost breakdown files
        uses: actions/download-artifact@v2
        with:
          path: /tmp
        
      - name: Setup Infracost
        uses: infracost/actions/setup@v1
        with:
          api-key: ${{ secrets.INFRACOST_API_KEY }}
          
      - name: Combine the results
        run: |
          infracost output --path="/tmp/infracost_jsons/*.json" --format=json --out-file=/tmp/infracost_combined.json
          
      - name: Post the comment
        uses: infracost/actions/comment@v1
        with:
          path: /tmp/infracost_combined.json
          behavior: update # Create a single comment and update it. See https://github.com/infracost/actions/tree/master/comment for other options