5b - Setting coverage standards with Flags

Codecov’s Flags helps this situation by grouping coverage reports by function. Let’s set up flags in our example so that we can simulate an instance where the backend is well-tested and wants to maintain high code coverage, while the frontend is new and only expected to increase with each new commit.

Add flags to the Codecov configuration

Re-write the codecov.yml file with the below

coverage:
  status:
    project: off
    patch: off

flag_management:
  individual_flags:
    - name: backend
      paths:
        - api/
      statuses:
        - type: project
          target: 100%
          threshold: 1%
    - name: frontend
      paths:
        - web/
      statuses:
        - type: project
          target: auto
          threshold: 1%

Notice that we are creating two flags backend and frontend that encompass the api and web directories, respectively. The backend flag will target 100% overall coverage, while the frontend flag is set to auto. This means that every new commit must maintain or raise the overall code coverage of the project.

Update the uploader call with flags

Update the workflows to send the proper flag with each coverage report

GitHub Actions

... 
    - name: Upload coverage reports to Codecov with GitHub Action
      uses: codecov/codecov-action@v2
      with:
        flags: backend

...
    - name: Upload coverage reports to Codecov with GitHub Action
      uses: codecov/codecov-action@v2
      with:
        flags: frontend

CircleCI

jobs:
  test-api:
    ...
    - codecov/upload:
        flags: backend
  test-frontend:
    ...
    - codecov/upload:
        flags: frontend

Commit your changes and push them to GitHub

git add .
git commit -m 'step5: add Codecov Flags'
git push origin step5

Now you see 4 status checks from Codecov that are passing.