A crude Github - Zendesk syncer

gistfile1.rb

class Zendesk

  ENDPOINT    = "https://[DOMAIN].zendesk.com/api/v2"
  USER        = "[YOUR_USER_NAME]"
  USER_ID     = 0 #[YOUR_USER_ID]
  TARGET_VIEW = 0 #[VIEW_ID]

  BODY_FIELD_ID       = 0 # [CUSTOM_BODY_FIELD_ID], We use an internal body
  REPO_NAME_FIELD_ID  = 0 #[REPO_NAME_FIELD_ID], We use a selectbox
  GITHUB_FIELD_ID     = 0 #[GITHUB_FIELD_ID], We use a checkbox

  def self.api
    Rails.logger.debug "Initializing Zendesk API client"

    ZendeskAPI::Client.new do |config|
      config.url = ENDPOINT
      config.username = USER
      config.token = Rails.application.config.zendesk_secret
    end
  end

  def self.tickets_in_target_view
    Rails.logger.debug "Gathering Zendesk tickets in target view"
    api.views.find(id: TARGET_VIEW).tickets(include: 'users')
  end

  def self.sync
    Rails.logger.debug "Starting Github - Zendesk sync process"

    tickets_in_target_view.each do |ticket|

      assignee_name = ticket.assignee.name
      subject       = ticket.subject
      body          = ticket.custom_fields.detect{ |cf| cf.id == BODY_FIELD_ID }.value
      repo_name     = ticket.custom_fields.detect{ |cf| cf.id == REPO_NAME_FIELD_ID }.value
      github        = ticket.custom_fields.detect{ |cf| cf.id == GITHUB_FIELD_ID }.value
      open          = ticket.status == "open"
      external_id   = !!ticket.external_id
      repo          = "[ORGANISATION]/#{repo_name}"

      if external_id
        number     = ticket.external_id.split('@').first
        change_set = changes_from_ticket(ticket)

        if any_changes?(change_set)
          update_github_issue(repo, number, subject, body, assignee_name, ticket.id) if any_issue_changes?(change_set)
          change_set.comments.each { |comment| create_github_comment(comment) }
          update_zendesk_external_id(ticket, number)
        else
          Rails.logger.debug "No changes for ticket ##{ticket.id}"
        end
      else
        issue = create_github_issue(repo, subject, body, assignee_name, ticket.id)
        update_zendesk_external_id(ticket, issue.number)
      end
    end
    nil
  end

  def self.any_changes? change_set
    !!change_set.body || !!change_set.subject || !!change_set.assignee || change_set.comments.present?
  end

  def self.any_issue_changes? change_set
    !!change_set.body || !!change_set.subject || !!change_set.assignee
  end

  def self.changes_from_ticket ticket
    Rails.logger.debug "Determining changeset for ticket ##{ticket.id}"

    timestamp = DateTime.parse(ticket.external_id.split('@').last)
    changes   = OpenStruct.new( assignee: nil, subject: nil, body: nil, comments: [])

    ticket.audits.each do |audit|
      if audit.created_at > timestamp
        audit.events.each do |event|
          case event.type
          when "Comment"
            if event.author_id != USER_ID
              changes.comments << { body: event.body,
                                    attachments: event.attachments.map{ |a| { file_name: a.file_name,
                                                                              url: a.content_url } } }
            end
          when "Change"
            case event.field_name
            when "subject"
              changes.subject = event.value
            when body_field_id.to_s
              changes.body = event.value
            when "assignee_id"
              changes.assignee = event.value
            end
          end
        end
      end
    end

    return changes
  end

  def self.create_github_comment repo, number, comment
    Rails.logger.debug "Creating comment on #{repo} ##{number}"

    body = comment[:body]
    comment[:attachments].each do |a|
      body += "\n\n[#{a[:file_name]}](#{a[:url]})"
    end
    Octokit.add_comment repo, number, body
  end

  def self.update_zendesk_external_id ticket, number
    Rails.logger.debug "Updating Zendesk external id for ticket ##{ticket.id}"

    ticket.external_id = "#{number}@#{DateTime.now}"
    ticket.save
  end

  def self.update_github_issue repo, number, subject, body, assignee_name, ticket_id
    Rails.logger.debug "Updating Github issue ##{number} on #{repo} with new values"

    body = github_issue_body(body, assignee_name, ticket_id)
    Octokit.update_issue repo, number, subject, body, labels: ["zendesk"]
  end

  def self.create_github_issue repo, subject, body, assignee_name, ticket_id
    Rails.logger.debug "Creating new Github issue on #{repo}"

    body  = github_issue_body(body, assignee_name, ticket_id)
    Octokit.create_issue repo, subject, body, labels: ["zendesk"]
  end

  def self.github_issue_body body, assignee_name, ticket_id
    body + "\n\n#{assignee_name} (ZD##{ticket.id})"
  end

end