rails のログに含まれる SQL を分析します

log_profiler.rb

# frozen_string_literal: true

Query = Struct.new(:type, :raw_sql, :model_name, :duration, keyword_init: true) do
  def abstract_sql
    raw_sql.gsub(/\d+/, 'N')
  end

  def unknown?
    type.nil? && model_name.nil?
  end

  def label
    if unknown?
      ['Unknown', 'Unknown']
    else
      [model_name, type]
    end
  end
end

class Line
  def initialize(string)
    @string = string.strip
  end

  def to_query
    try_template_query || try_another_query
  end

  private

  def try_template_query
    match_data = @string.match(/(\w+) (Load|Exists\?|Update|Create) \(([\d.])+ms\)(.+)/)
    _, model_name, query_type, duration, raw_sql = match_data.to_a

    if query_type
      Query.new(model_name: model_name, type: query_type, raw_sql: raw_sql, duration: duration.to_f)
    end
  end

  def try_another_query
    match_data = @string.match(/(.*) \(([\d.])+ms\)(.+)/)
    _, _, duration, raw_sql = match_data.to_a

    if duration
      Query.new(raw_sql: raw_sql, duration: duration.to_f)
    end
  end
end

class LogProfiler
  def initialize(raw_message)
    @raw_message = raw_message
    @queries = init_queries
  end

  def print
    puts("|                               MODEL NAME |       TYPE | DURATION |  COUNT |")
    puts("|------------------------------------------|------------|----------|--------|")
    puts(table)
    puts("Query total time: #{query_total_time}ms")
    puts("Unkown Query Samples:")
    puts(unknown_query_samples.join("\n\n"))
  end

  private

  def query_total_time
    @queries.sum(&:duration)
  end

  def unknown_query_samples
    @queries
      .filter(&:unknown?)
      .map(&:abstract_sql)
      .tally
      .map { |sql, count| "#{count}\t#{sql}" }
  end

  def table
    group = @queries.group_by { |query| query.label }
    result = group.map { |(model_name, type), queries| [model_name, type, queries.sum(&:duration), queries.count] }
    result = result.sort_by { |item| - item[-2] }
    result.map do |model_name, type, duration, count|
      format("| %40s | %10s | %8s | %6s |", model_name, type, duration, count)
    end
  end

  def init_queries
    @raw_message.each_line.filter_map { Line.new(_1).to_query }
  end
end

log = File.read(ARGV[0])
profiler = LogProfiler.new(log)
profiler.print