git_repository.rb

require "rugged"

class GitRepository < ApplicationRecord
  include AuthenticationMixin

  GIT_REPO_DIRECTORY = Rails.root.join('data/git_repos')

  validates :url, :format => URI::regexp(%w(http https file)), :allow_nil => false

  default_value_for :verify_ssl, OpenSSL::SSL::VERIFY_PEER
  validates :verify_ssl, :inclusion => {:in => [OpenSSL::SSL::VERIFY_NONE, OpenSSL::SSL::VERIFY_PEER]}

  has_many :git_branches, :dependent => :destroy
  has_many :git_tags, :dependent => :destroy
  after_destroy :delete_repo_dir # TODO: Need to distribute this to all systems

  INFO_KEYS = %w(commit_sha commit_message commit_time name).freeze

  def refresh
    update_repo
    transaction do
      refresh_branches
      refresh_tags
      self.last_refresh_on = Time.now.utc
      save!
    end
  end

  def branch_info(name)
    ensure_refreshed
    branch = git_branches.detect { |item| item.name == name }
    raise "Branch #{name} not found" unless branch
    branch.attributes.slice(*INFO_KEYS)
  end

  def tag_info(name)
    ensure_refreshed
    tag = git_tags.detect { |item| item.name == name }
    raise "Tag #{name} not found" unless tag
    tag.attributes.slice(*INFO_KEYS)
  end

  def entries(ref, path)
    ensure_refreshed
    with_worktree do |worktree|
      worktree.ref = ref
      worktree.entries(path)
    end
  end

  def checkout(ref, path)
    ensure_refreshed
    with_worktree do |worktree|
      message = "Checking out #{url}@#{ref} to #{path}..."
      _log.info(message)
      worktree.ref = ref
      worktree.checkout(path)
      _log.info("#{message}...Complete")
    end
    path
  end

  def directory_name
    raise ActiveRecord::RecordNotSaved if new_record?

    File.join(GIT_REPO_DIRECTORY, id.to_s)
  end

  def self_signed_cert_cb(_valid, _host)
    true
  end

  def with_worktree
    handling_worktree_errors do
      yield worktree
    end
  end

  def update_repo
    with_worktree do |worktree|
      message = "Updating #{url} in #{directory_name}..."
      _log.info(message)
      worktree.send(:fetch_and_merge)
      _log.info("#{message}...Complete")
    end
    @updated_repo = true
  end

  private

  def ensure_refreshed
    refresh unless @updated_repo
  end

  def refresh_branches
    with_worktree do |worktree|
      current_branches = git_branches.index_by(&:name)
      worktree.branches(:remote).each do |branch|
        info = worktree.branch_info(branch)
        attrs = {:name           => branch,
                 :commit_sha     => info[:commit_sha],
                 :commit_time    => info[:time],
                 :commit_message => info[:message]}

        stored_branch = current_branches.delete(branch)
        stored_branch ? stored_branch.update_attributes!(attrs) : git_branches.create!(attrs)
      end
      git_branches.delete(current_branches.values)
    end
  end

  def refresh_tags
    with_worktree do
      current_tags = git_tags.index_by(&:name)
      worktree.tags.each do |tag|
        info = worktree.tag_info(tag)
        attrs = {:name           => tag,
                 :commit_sha     => info[:commit_sha],
                 :commit_time    => info[:time],
                 :commit_message => info[:message]}

        stored_tag = current_tags.delete(tag)
        stored_tag ? stored_tag.update_attributes(attrs) : git_tags.create!(attrs)
      end
      git_tags.delete(current_tags.values)
    end
  end

  def worktree
    @worktree ||= begin
      clone_repo unless Dir.exist?(directory_name)
      fetch_worktree
    end
  end

  def fetch_worktree
    GitWorktree.new(worktree_params)
  end

  def clone_repo
    handling_worktree_errors do
      message = "Cloning #{url} to #{directory_name}..."
      _log.info(message)
      GitWorktree.new(worktree_params.merge(:clone => true, :url => url))
      @updated_repo = true
      _log.info("#{message}...Complete")
    end
  end

  def handling_worktree_errors
    yield
  rescue ::Rugged::NetworkError => err
    raise MiqException::MiqUnreachableError, err.message
  rescue => err
    raise MiqException::Error, err.message
  end

  def worktree_params
    params = {:path => directory_name}
    params[:certificate_check] = method(:self_signed_cert_cb) if verify_ssl == OpenSSL::SSL::VERIFY_NONE
    if authentications.any?
      params[:username] = default_authentication.userid
      params[:password] = default_authentication.password
    end
    params
  end

  def delete_repo_dir
    FileUtils.rm_rf(directory_name)
  end
end