File: explain_subscriber.rb

package info (click to toggle)
rails 2%3A6.0.3.7%2Bdfsg-2%2Bdeb11u2
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 70,976 kB
  • sloc: ruby: 271,623; javascript: 19,043; yacc: 46; sql: 43; makefile: 28; sh: 18
file content (34 lines) | stat: -rw-r--r-- 1,095 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
# frozen_string_literal: true

require "active_support/notifications"
require "active_record/explain_registry"

module ActiveRecord
  class ExplainSubscriber # :nodoc:
    def start(name, id, payload)
      # unused
    end

    def finish(name, id, payload)
      if ExplainRegistry.collect? && !ignore_payload?(payload)
        ExplainRegistry.queries << payload.values_at(:sql, :binds)
      end
    end

    # SCHEMA queries cannot be EXPLAINed, also we do not want to run EXPLAIN on
    # our own EXPLAINs no matter how loopingly beautiful that would be.
    #
    # On the other hand, we want to monitor the performance of our real database
    # queries, not the performance of the access to the query cache.
    IGNORED_PAYLOADS = %w(SCHEMA EXPLAIN)
    EXPLAINED_SQLS = /\A\s*(with|select|update|delete|insert)\b/i
    def ignore_payload?(payload)
      payload[:exception] ||
        payload[:cached] ||
        IGNORED_PAYLOADS.include?(payload[:name]) ||
        payload[:sql] !~ EXPLAINED_SQLS
    end

    ActiveSupport::Notifications.subscribe("sql.active_record", new)
  end
end