google_meet_service.rb

require 'googleauth'
require 'google/apis'
require 'google/apis/calendar_v3'

module GoogleMeetService
  def self.create_google_event(event)
    authorize_client
    google_event = create_calendar_event(event)
    updated_google_event = update_calendar_event(event,google_event)
    event.update_attribute(:conference_link,updated_google_event.hangout_link)
  end

  def self.create_calendar_event(event)
    new_event_payload = Google::Apis::CalendarV3::Event.new(
      summary: "Event_#{event.id}",
      description: "Event_#{event.id} : #{event.description}",
      start: { date_time: event.start_date.iso8601 },
      end: { date_time: event.end_date.iso8601 }
    )
    new_event = @client.insert_event('primary',new_event_payload)
    @client.get_event('primary',new_event.id)
  end

  def self.authorize_client
    scopes = [
      "https://www.googleapis.com/auth/calendar",
      "https://www.googleapis.com/auth/calendar.events"
    ]
    File.open('google_credentials.json', 'w') do |f|
      f.puts Rails.application.credentials.GOOGLE_CREDENTIALS.to_json
    end
    authorizer = Google::Auth::ServiceAccountCredentials.make_creds(json_key_io: File.open('google_credentials.json'),scope: scopes)
    File.delete('google_credentials.json') if File.exist?('google_credentials.json')
    @client  = Google::Apis::CalendarV3::CalendarService.new
    @client.authorization = authorizer
    @client.authorization.fetch_access_token!
  end

  def self.update_calendar_event(event,google_event)
    random_meet_id = "#{('a'..'z').to_a.shuffle[0,3].join}-#{('a'..'z').to_a.shuffle[0,4].join}-#{('a'..'z').to_a.shuffle[0,3].join}"
    update_event_payload = Google::Apis::CalendarV3::Event.new(
      summary: "Event_#{event.id}",
      description: "Event_#{event.id} : #{event.description}",
      start: { date_time: event.start_date.iso8601 },
      end: { date_time: event.end_date.iso8601 },
      conference_data: {
        conference_id: "#{random_meet_id}",
        # conference_solution: {
        #   key:{
        #     type: "hangoutsMeet"
        #   },
        #   name: 'meet'
        # },
        create_request: {
          request_id: "#{('a'..'z').to_a.shuffle[0,10].join}",
          # conference_solution_key: {
          #   type: "hangoutsMeet"
          # }
        }
      }
    )
    updated_event = @client.update_event('primary',google_event.id,update_event_payload,{conference_data_version: 1})
  end
 end