Merge pull request #57 from marcelofabri/circle-ci-workaround

Calling CircleCI API when CI_PULL_REQUEST is not set

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## Master
 
+* Calling CircleCI API when `CI_PULL_REQUEST` is not set - marcelofabri
 * Look inside PR JSON for the commit range (instead of getting from CI providers) - marcelofabri
 * Adds `pr_labels` to DSL - marcelofabri
 * Makes the CircleCI provider validate, but not run on non-PR builds - orta

lib/danger/ci_source/circle.rb

@@ -1,16 +1,43 @@
 # https://circleci.com/docs/environment-variables
 require 'uri'
+require 'danger/circle_api'
 
 module Danger
   module CISource
     class CircleCI < CI
       def self.validates?(env)
-        return !env["CIRCLE_BUILD_NUM"].nil? && !env["CI_PULL_REQUEST"].nil?
+        return false if env["CIRCLE_BUILD_NUM"].nil?
+        return true unless env["CI_PULL_REQUEST"].nil?
+
+        return !env["CIRCLE_PROJECT_USERNAME"].nil? && !env["CIRCLE_PROJECT_REPONAME"].nil?
+      end
+
+      def client
+        @client ||= CircleAPI.new(@circle_token)
+      end
+
+      def fetch_pull_request_url(repo_slug, build_number)
+        build_json = client.fetch_build(repo_slug, build_number)
+        build_json[:pull_request_urls].first
+      end
+
+      def pull_request_url(env)
+        url = env["CI_PULL_REQUEST"]
+
+        if url.nil? && !env["CIRCLE_PROJECT_USERNAME"].nil? && !env["CIRCLE_PROJECT_REPONAME"].nil?
+          repo_slug = env["CIRCLE_PROJECT_USERNAME"] + "/" + env["CIRCLE_PROJECT_REPONAME"]
+          url = fetch_pull_request_url(repo_slug, env["CIRCLE_BUILD_NUM"])
+        end
+
+        url
       end
 
       def initialize(env)
-        if URI.parse(env["CI_PULL_REQUEST"]).path.split("/").count == 5
-          paths = URI.parse(env["CI_PULL_REQUEST"]).path.split("/")
+        @circle_token = env["CIRCLE_CI_API_TOKEN"]
+        url = pull_request_url(env)
+
+        if URI.parse(url).path.split("/").count == 5
+          paths = URI.parse(url).path.split("/")
           # The first one is an extra slash, ignore it
           self.repo_slug = paths[1] + "/" + paths[2]
           self.pull_request_id = paths[4]

lib/danger/circle_api.rb

@@ -0,0 +1,23 @@
+require 'faraday'
+
+module Danger
+  class CircleAPI
+    attr_accessor :circle_token
+
+    def initialize(circle_token = nil)
+      self.circle_token = circle_token
+    end
+
+    def client
+      @client ||= Faraday.new(url: 'https://circleci.com/api/v1')
+    end
+
+    def fetch_build(repo_slug, build_number)
+      url = "project/#{repo_slug}/#{build_number}"
+      params = { :'circle-token' => circle_token }
+      response = client.get url, params, accept: 'application/json'
+      json = JSON.parse(response.body, symbolize_names: true)
+      json
+    end
+  end
+end