Automated bundle update process and creation of pull request

gistfile1.rb

require 'bundler/cli'
require 'git'
require 'octokit'

BRANCH_NAME    = 'gem-updates'
COMMIT_MESSAGE = 'Update gems'
# ASSIGNEE       = 'pengwynn' # update to assing pull request

git            = Git.open(Dir.pwd)
github         = Octokit::Client.new(access_token: ENV['GITHUB_ACCESS_TOKEN'])

repository     = git.remote(:origin).url.split(':')[1].chomp('.git')
default_branch = github.repository(repository).default_branch

# Checkout new branch and get up to date
git.branch(BRANCH_NAME).checkout
git.pull(:origin, default_branch)

# Update gems
Bundler::CLI.start([:update])

# Commit changes
git.add('Gemfile.lock')
git.commit(COMMIT_MESSAGE)
git.push(:origin, BRANCH_NAME)

# Create Github Pull request
pull = github.create_pull_request(repository, default_branch, BRANCH_NAME, COMMIT_MESSAGE)

# Add assignee
github.update_issue(repository, pull.number, assignee: ASSIGNEE) if defined?(ASSIGNEE) && ASSIGNEE

# Cleanup branch
git.branch('master').checkout
git.branch(BRANCH_NAME).delete