class Danger::CircleCI

### CI Setup

For setting up CircleCI, we recommend turning on “Only build pull requests” in “Advanced Settings.” Without this enabled, it’s trickier for Danger to determine whether you’re in a pull request or not, as the environment metadata isn’t as reliable.

A common scenario is when CircleCI begins building a commit before the commit becomes associated with a PR (e.g. a developer pushes their branch to the remote repo for the first time. CircleCI spins up and begins building. Moments later the developer creates a PR on GitHub. Since the build process started before the PR existed, Danger won’t be able to use the Circle-provided environment variables to retrieve PR metadata.)

With “Only build pull requests” enabled, you can add ‘bundle exec danger` to your `config.yml` (Circle 2.0).

e.g.

```yaml
- run: bundle exec danger --verbose
```

And that should be it!

### Token Setup

If “Only build pull requests” can’t be enabled for your project, Danger can still work by relying on CircleCI’s API to retrieve PR metadata, which will require an API token.

  1. Go to your project > Settings > API Permissions. Create a token with scope “view-builds” and a label like “DANGER_CIRCLE_CI_API_TOKEN”.

  2. Settings > Environment Variables. Add the token as a CircleCI environment variable, which exposes it to the Danger process.

There is no difference here for OSS vs Closed, both scenarios will need this environment variable.

With these pieces in place, Danger should be able to work as expected.

Public Class Methods

new(env) click to toggle source
# File lib/danger/ci_source/circle.rb, line 66
def initialize(env)
  self.repo_url = env["CIRCLE_REPOSITORY_URL"]
  pr_url = env["CI_PULL_REQUEST"] || env["CIRCLE_PULL_REQUEST"]

  # If it's not a real URL, use the Circle API
  unless pr_url && URI.parse(pr_url).kind_of?(URI::HTTP)
    api = CircleAPI.new
    pr_url = api.pull_request_url(env)
  end

  # We should either have got it via the API, or
  # an ENV var.
  pr_path = URI.parse(pr_url).path.split("/")
  if pr_path.count == 5
    # The first one is an extra slash, ignore it
    self.repo_slug = pr_path[1] + "/" + pr_path[2]
    self.pull_request_id = pr_path[4]

  else
    message = "Danger::Circle.rb considers this a PR, " \
              "but did not get enough information to get a repo slug" \
              "and PR id.\n\n" \
              "PR path: #{pr_url}\n" \
              "Keys: #{env.keys}"
    raise message.red
  end
end
validates_as_ci?(env) click to toggle source

Side note: CircleCI is complicated. The env vars for PRs are not guaranteed to exist if the build was triggered from a commit, to look at examples of the different types of CI states, see this repo: github.com/orta/show_circle_env

# File lib/danger/ci_source/circle.rb, line 45
def self.validates_as_ci?(env)
  env.key? "CIRCLE_BUILD_NUM"
end
validates_as_pr?(env) click to toggle source
# File lib/danger/ci_source/circle.rb, line 49
def self.validates_as_pr?(env)
  # This will get used if it's available, instead of the API faffing.
  return true if env["CI_PULL_REQUEST"] && !env["CI_PULL_REQUEST"].empty?
  return true if env["CIRCLE_PULL_REQUEST"] && !env["CIRCLE_PULL_REQUEST"].empty?

  # Real-world talk, it should be worrying if none of these are in the environment
  return false unless ["DANGER_CIRCLE_CI_API_TOKEN", "CIRCLE_PROJECT_USERNAME", "CIRCLE_PROJECT_REPONAME", "CIRCLE_BUILD_NUM"].all? { |x| env[x] && !env[x].empty? }

  # Uses the Circle API to determine if it's a PR otherwise
  api = CircleAPI.new
  api.pull_request?(env)
end

Public Instance Methods

supported_request_sources() click to toggle source
# File lib/danger/ci_source/circle.rb, line 62
def supported_request_sources
  @supported_request_sources ||= [Danger::RequestSources::GitHub, Danger::RequestSources::BitbucketCloud]
end