write elastic ruby agent apm to file

file_adapter.rb

# frozen_string_literal: true

class FileAdapter
  include ElasticAPM::Logging

  def initialize(config)
    @config = config
    @mutex = Mutex.new

    @logger_file = File.new('log/apm.log', 'a+')
  end

  def write(str)
    return false if @config.disable_send

    begin
      @mutex.synchronize do
        @logger_file.puts(str)
      end
    rescue IOError => e
      error('FileAdapter error: %s', e.inspect)
    rescue Errno::EPIPE => e
      error('FileAdapter error: %s', e.inspect)
    rescue Exception => e
      error('FileAdapter error: %s', e.inspect)
    end
  end

  def flush(reason = :force)
    @mutex.synchronize do
      error('FileAdapter flush: %s', reason)
      @logger_file&.close
    end
  end
end

gem 'elastic-apm'

ElasticAPM::Transport::Worker.adapter = FileAdapter # application.rb after Bundler.require(*Rails.groups)

   create_table :metricsets do |t|
      t.jsonb :samples
      t.jsonb :transaction
      t.jsonb :span

      t.timestamps
    end

    create_table :spans, id: :string do |t|
      t.string :transaction_id
      t.string :parent_id
      t.string :name
      t.string :t # type
      t.decimal :duration
      t.jsonb :context
      t.jsonb :stacktrace
      t.string :trace_id

      t.timestamps
    end

    create_table :transactions, id: :string do |t|
      t.string :trace_id
      t.string :parent_id
      t.string :name
      t.string :t # type
      t.string :result
      t.decimal :duration
      t.boolean :sampled
      t.jsonb :context
      t.jsonb :span_count

      t.timestamps
    end