class Danger::CircleCI


With these pieces in place, Danger should be able to work as expected.
There is no difference here for OSS vs Closed, both scenarios will need this environment variable.
2. Settings > Environment Variables. Add the token as a CircleCI environment variable, which exposes it to the Danger process.
1. Go to your project > Settings > API Permissions. Create a token with scope “view-builds” and a label like “DANGER_CIRCLE_CI_API_TOKEN”.
to retrieve PR metadata, which will require an API token.
If “Only build pull requests” can’t be enabled for your project, Danger can still work by relying on CircleCI’s API
### Token Setup
And that should be it!
“‘
- run: bundle exec danger –verbose
“`yaml
e.g.
With “Only build pull requests” enabled, you can add `bundle exec danger` to your `config.yml` (Circle 2.0).
Danger won’t be able to use the Circle-provided environment variables to retrieve PR metadata.)
Moments later the developer creates a PR on GitHub. Since the build process started before the PR existed,
(e.g. a developer pushes their branch to the remote repo for the first time. CircleCI spins up and begins building.
A common scenario is when CircleCI begins building a commit before the commit becomes associated with a PR
isn’t as reliable.
it’s trickier for Danger to determine whether you’re in a pull request or not, as the environment metadata
For setting up CircleCI, we recommend turning on “Only build pull requests” in “Advanced Settings.” Without this enabled,
### CI Setup

def self.validates_as_ci?(env) 

def self.validates_as_ci?(env)
  env.key? "CIRCLE_BUILD_NUM"
end

def self.validates_as_pr?(env) 

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

def initialize(env) 

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

def supported_request_sources 

def supported_request_sources
  @supported_request_sources ||= [Danger::RequestSources::GitHub, Danger::RequestSources::BitbucketCloud]
end