debian-mirror-gitlab/lib/gitlab/metrics/requests_rack_middleware.rb
2021-06-08 01:23:25 +05:30

109 lines
4.1 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Metrics
class RequestsRackMiddleware
HTTP_METHODS = {
"delete" => %w(200 202 204 303 400 401 403 404 500 503),
"get" => %w(200 204 301 302 303 304 307 400 401 403 404 410 422 429 500 503),
"head" => %w(200 204 301 302 303 401 403 404 410 500),
"options" => %w(200 404),
"patch" => %w(200 202 204 400 403 404 409 416 500),
"post" => %w(200 201 202 204 301 302 303 304 400 401 403 404 406 409 410 412 422 429 500 503),
"put" => %w(200 202 204 400 401 403 404 405 406 409 410 422 500)
}.freeze
HEALTH_ENDPOINT = /^\/-\/(liveness|readiness|health|metrics)\/?$/.freeze
FEATURE_CATEGORY_HEADER = 'X-Gitlab-Feature-Category'
FEATURE_CATEGORY_DEFAULT = 'unknown'
# These were the top 5 categories at a point in time, chosen as a
# reasonable default. If we initialize every category we'll end up
# with an explosion in unused metric combinations, but we want the
# most common ones to be always present.
FEATURE_CATEGORIES_TO_INITIALIZE = ['authentication_and_authorization',
'code_review', 'continuous_integration',
'not_owned', 'source_code_management',
FEATURE_CATEGORY_DEFAULT].freeze
def initialize(app)
@app = app
end
def self.http_requests_total
::Gitlab::Metrics.counter(:http_requests_total, 'Request count')
end
def self.rack_uncaught_errors_count
::Gitlab::Metrics.counter(:rack_uncaught_errors_total, 'Request handling uncaught errors count')
end
def self.http_request_duration_seconds
::Gitlab::Metrics.histogram(:http_request_duration_seconds, 'Request handling execution time',
{}, [0.05, 0.1, 0.25, 0.5, 0.7, 1, 2.5, 5, 10, 25])
end
def self.http_health_requests_total
::Gitlab::Metrics.counter(:http_health_requests_total, 'Health endpoint request count')
end
def self.initialize_metrics
# This initialization is done to avoid gaps in scraped metrics after
# restarts. It makes sure all counters/histograms are available at
# process start.
#
# For example `rate(http_requests_total{status="500"}[1m])` would return
# no data until the first 500 error would occur.
HTTP_METHODS.each do |method, statuses|
http_request_duration_seconds.get({ method: method })
statuses.product(FEATURE_CATEGORIES_TO_INITIALIZE) do |status, feature_category|
http_requests_total.get({ method: method, status: status, feature_category: feature_category })
end
end
end
def call(env)
method = env['REQUEST_METHOD'].downcase
method = 'INVALID' unless HTTP_METHODS.key?(method)
started = Time.now.to_f
health_endpoint = health_endpoint?(env['PATH_INFO'])
status = 'undefined'
feature_category = nil
begin
status, headers, body = @app.call(env)
elapsed = Time.now.to_f - started
feature_category = headers&.fetch(FEATURE_CATEGORY_HEADER, nil)
unless health_endpoint
RequestsRackMiddleware.http_request_duration_seconds.observe({ method: method }, elapsed)
end
[status, headers, body]
rescue StandardError
RequestsRackMiddleware.rack_uncaught_errors_count.increment
raise
ensure
if health_endpoint
RequestsRackMiddleware.http_health_requests_total.increment(status: status.to_s, method: method)
else
RequestsRackMiddleware.http_requests_total.increment(
status: status.to_s,
method: method,
feature_category: feature_category.presence || FEATURE_CATEGORY_DEFAULT
)
end
end
end
def health_endpoint?(path)
return false if path.blank?
HEALTH_ENDPOINT.match?(CGI.unescape(path))
end
end
end
end