Module: GovukJsonLogging

Defined in:
lib/govuk_app_config/govuk_json_logging.rb

Defined Under Namespace

Classes: Configuration

Class Method Summary collapse

Class Method Details

.configure(&block) ⇒ Object 



18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
 
# File 'lib/govuk_app_config/govuk_json_logging.rb', line 18

def self.configure(&block)
  # Fixes the monkey patch from the logstasher gem to support Rails 7
  config = Rails.application.config.logstasher
  if (!config.controller_monkey_patch && config.controller_monkey_patch != false) || config.controller_monkey_patch == true
    require_relative "./govuk_json_logging/rails_ext/action_controller/metal/instrumentation"
    # Prevent the old monkey patch being applied
    config.controller_monkey_patch = false
  end

  configuration = Configuration.new

  configuration.instance_eval(&block) if block_given?

  # We disable buffering, so that logs aren't lost on crash or delayed
  # indefinitely while troubleshooting.
  $stdout.sync = true

  Rails.logger = ActiveSupport::Logger.new($stdout, level: Rails.logger.level)
  Rails.logger.formatter = proc { |severity, datetime, _progname, msg|
    hash = {
      "@timestamp": datetime.utc.iso8601(3),
      message: msg,
      level: severity,
      tags: %w[rails],
    }

    if defined?(GdsApi::GovukHeaders) && !GdsApi::GovukHeaders.headers[:govuk_request_id].nil?
      hash[:govuk_request_id] = GdsApi::GovukHeaders.headers[:govuk_request_id]
    end

    "#{hash.to_json}\n"
  }

  LogStasher.add_custom_fields do |fields|
    # Mirrors Nginx request logging, e.g. GET /path/here HTTP/1.1
    fields[:request] = "#{request.request_method} #{request.fullpath} #{request.headers['SERVER_PROTOCOL']}"

    fields[:govuk_request_id] = request.headers["GOVUK-Request-Id"]
    fields[:varnish_id] = request.headers["X-Varnish"]
    fields[:govuk_app_config] = GovukAppConfig::VERSION

    instance_exec(fields, &configuration.custom_fields_block) if block_given?
  end

  Rails.application.config.logstasher.enabled = true

  # Log controller actions so that we can graph response times.
  Rails.application.config.logstasher.controller_enabled = true

  # The other loggers are not that interesting in production.
  Rails.application.config.logstasher.mailer_enabled = false
  Rails.application.config.logstasher.record_enabled = false
  Rails.application.config.logstasher.view_enabled = false
  Rails.application.config.logstasher.job_enabled = false

  # Elasticsearch index expect source to be an object and logstash defaults
  # source to be the host IP address causing logs to be dropped.
  Rails.application.config.logstasher.source = {}
  # Elasticsearch index expect error to be an object and logstash defaults
  # error to be a string causing logs to be dropped.
  Rails.application.config.logstasher.field_renaming = {
    error: :error_message,
  }

  Rails.application.config.logstasher.logger = Logger.new(
    $stdout,
    level: Rails.logger.level,
    formatter: proc { |_severity, _datetime, _progname, msg|
      "#{msg.is_a?(String) ? msg : msg.inspect}\n"
    },
  )
  Rails.application.config.logstasher.suppress_app_log = true

  if defined?(GdsApi::Base)
    GdsApi::Base.default_options ||= {}

    # The gds-api-adapters gem logs JSON to describe the requests it makes and
    # the responses it gets, so direct this to the logstasher logger.
    GdsApi::Base.default_options[:logger] = Rails.application.config.logstasher.logger
  end
end