Post code coverage as a comment to a Github PR from Circle CI

circle.yml

machine:
  node:
    version: 6.1.0
    
test:
  post:
    - cp -r coverage $CIRCLE_ARTIFACTS
    - mkdir -p $CIRCLE_TEST_REPORTS/junit
    - mv test-report/*.xml $CIRCLE_TEST_REPORTS/junit/test-results.xml
    - bundle exec ruby github-pr.rb

Gemfile

source "https://rubygems.org"

gem "octokit"
gem "nokogiri"
gem "json"

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    addressable (2.5.0)
      public_suffix (~> 2.0, >= 2.0.2)
    faraday (0.11.0)
      multipart-post (>= 1.2, < 3)
    json (2.0.2)
    mini_portile2 (2.1.0)
    multipart-post (2.0.0)
    nokogiri (1.7.0.1)
      mini_portile2 (~> 2.1.0)
    octokit (4.6.2)
      sawyer (~> 0.8.0, >= 0.5.3)
    public_suffix (2.0.5)
    sawyer (0.8.1)
      addressable (>= 2.3.5, < 2.6)
      faraday (~> 0.8, < 1.0)

PLATFORMS
  ruby

DEPENDENCIES
  json
  nokogiri
  octokit

BUNDLED WITH
   1.13.7

github-pr-coverage.rb

# This is intended to be used from Circle CI, if you want to have the
# coverage posted on Github but can't use an external service.
#
# You'll need to add a GITHUB_ACCESS_TOKEN to your CI secret vars
#
# The coverage needs to be reported in clover format for this to work
#
# Configuration

REPOSITORY = "aurbano/robinhood-node"
COVERAGE_PATH = "coverage/clover.xml"

# ------------------------------------

require 'octokit'
require 'uri'
require 'nokogiri'
require 'net/http'
require 'json'

def check_env(key)
  unless ENV.has_key?(key)
    puts "Missing #{key} env variable"
    exit
  end
  value = ENV[key]
  unless value.length > 0
    puts "#{key} is not set"
    exit
  end
end

check_env('GITHUB_ACCESS_TOKEN')
check_env('CI_PULL_REQUEST')

client = Octokit::Client.new :access_token => ENV['GITHUB_ACCESS_TOKEN']

PULL_REQUEST_URL = ENV['CI_PULL_REQUEST']
PULL_REQUEST_ID = URI(PULL_REQUEST_URL).path.split('/').last

report = File.open(COVERAGE_PATH, "rb")
@coverage = Nokogiri::XML(report.read)

def get_coverage(type)
  100 * Float(@coverage.at_xpath('//coverage/project/metrics').attribute("covered#{type}").value) / Float(@coverage.at_xpath('//coverage/project/metrics').attribute(type).value)
end

lines = get_coverage('statements')
statements = get_coverage('elements')
branches = get_coverage('conditionals')
functions = get_coverage('methods')

puts "Coverage: S #{statements.round}%, B #{branches.round}%, L #{lines.round}%, F #{functions.round}%"

comment = "**Code Coverage:**\n"\
          " * Statements: `#{statements.round}%`\n"\
          " * Branches: `#{branches.round}%`\n"\
          " * Lines: `#{lines.round}%`\n"\
          " * Functions: `#{functions.round}%`"

## The following commented out code was intended to link to the coverage artifact from the comment
## but the attribute URL is generated AFTER this script runs, so there is no way at the moment
## to get a link to the final attributes.

# Now get URL of coverage report:
# check_env('CIRCLE_CI_TOKEN');
# circle_token = ENV['CIRCLE_CI_TOKEN']
# build = ENV['CIRCLE_BUILD_NUM']
# puts 'Requesting attribute list...'
# response = Net::HTTP.get_response(URI("https://circleci.com/api/v1.1/project/github/#{REPOSITORY}/#{build}/attributes?circle-token=#{circle_token}"))
# puts response.body
# attributes = JSON.parse(response.body)
# attribute_url = ''
#
# for attribute in attributes
#   if attribute['pretty_path'] == '$CIRCLE_ARTIFACTS/coverage/lcov-report/index.html'
#     attribute_url = attribute['url']
#   end
# end
# puts "Attribute URL: #{attribute_url}"
# comment = "#{comment}\n\n*[Coverage details](#{attribute_url})*"

puts 'Posting comment...'

client.add_comment(REPOSITORY, PULL_REQUEST_ID, comment)

puts 'Done!'