A simply extend the Fastlane Action to enable downloading the uploaded Universal APK from the Google Play Console.

apk_downloader.rb

# File location: /actions/apk_downloader.rb
module Fastlane
  module Actions
    module SharedValues
      APK_DOWNLOADER_CUSTOM_VALUE = :APK_DOWNLOADER_CUSTOM_VALUE
    end

    class ApkDownloaderAction < Action
      
      def self.run(params)
        require 'supply'
        require 'supply/options'

        Supply.config = params
        supplyClient = Supply::Client.make_from_config
        googleClient = supplyClient.client

        apks = googleClient.list_generatedapks(params[:package_name], params[:version_code])
        downloadID = apks.generated_apks[0].generated_universal_apk.download_id
        UI.message("ApkDownloaderAction...\npackageName: #{params[:package_name]}\nversionCode: #{params[:version_code]}\nDownloadID: #{downloadID}")
        UI.message("🕗 Downloading APK...")
        apk = googleClient.download_generatedapk(params[:package_name], params[:version_code], downloadID, download_dest: params[:export_file_path]) {
          UI.success("✅  Successfully download apk in '#{params[:export_file_path]}'")
        }
      end

      #####################################################
      # @!group Documentation
      #####################################################

      def self.description
        "Download generated Apk from google play console."
      end

      def self.details
        "Download generated Apk from google play console."
      end

      def self.available_options
        require 'supply'
        require 'supply/options'

        defaultOptions = [
          :package_name,
          :track,
          :json_key,
          :json_key_data,
          :root_url,
          :timeout,
          :key,
          :version_code
        ]

        result = Supply::Options.available_options.select do |option|
          defaultOptions.include?(option.key)
        end

        result.append(FastlaneCore::ConfigItem.new(key: :export_file_path,
        env_name: "FL_APK_EXPORT_FILE_PATH",
        description: "APK Export File Path",
        is_string: true,
        default_value: ""))
      end

      def self.output
        [
        ]
      end

      def self.return_value
      end

      def self.authors
        ["zhgchgli"]
      end

      def self.is_supported?(platform)
        platform == :android
      end
    end
  end
end

Fastfile

  lane :test  do | options |
    apk_downloader(json_key: "./xxx@xxx.iam.gserviceaccount.com.json", package_name: "m.zhgchg.li", version_code:1000, export_file_path: "./zhgchgli.apk")
  end

i receive "The following App Bundle version code could not be found." when i call list_generatedapks method，can you help me