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
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
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
# rubocop:disable Style/ClassVars
module Gitlab
module Metrics
module Concern
extend ActiveSupport::Concern
included do
@@_metric_provider_mutex ||= Mutex.new
@@_metrics_provider_cache = {}
end
class_methods do
def reload_metric!(name)
@@_metrics_provider_cache.delete(name)
end
private
def define_metric(type, name, opts = {}, &block)
if respond_to?(name)
raise ArgumentError, "method #{name} already exists"
end
define_singleton_method(name) do
# inlining fetch_metric method to avoid method call overhead when instrumenting hot spots
@@_metrics_provider_cache[name] || init_metric(type, name, opts, &block)
end
end
def fetch_metric(type, name, opts = {}, &block)
@@_metrics_provider_cache[name] || init_metric(type, name, opts, &block)
end
def init_metric(type, name, opts = {}, &block)
options = MetricOptions.new(opts)
options.evaluate(&block)
if disabled_by_feature(options)
synchronized_cache_fill(name) { NullMetric.instance }
else
synchronized_cache_fill(name) { build_metric!(type, name, options) }
end
end
def synchronized_cache_fill(key)
@@_metric_provider_mutex.synchronize do
@@_metrics_provider_cache[key] ||= yield
end
end
def disabled_by_feature(options)
options.with_feature && !Feature.get(options.with_feature).enabled?
end
def build_metric!(type, name, options)
case type
when :gauge
Gitlab::Metrics.gauge(name, options.docstring, options.base_labels, options.multiprocess_mode)
when :counter
Gitlab::Metrics.counter(name, options.docstring, options.base_labels)
when :histogram
Gitlab::Metrics.histogram(name, options.docstring, options.base_labels, options.buckets)
when :summary
raise NotImplementedError, "summary metrics are not currently supported"
else
raise ArgumentError, "uknown metric type #{type}"
end
end
# Fetch and/or initialize counter metric
# @param [Symbol] name
# @param [Hash] opts
def fetch_counter(name, opts = {}, &block)
fetch_metric(:counter, name, opts, &block)
end
# Fetch and/or initialize gauge metric
# @param [Symbol] name
# @param [Hash] opts
def fetch_gauge(name, opts = {}, &block)
fetch_metric(:gauge, name, opts, &block)
end
# Fetch and/or initialize histogram metric
# @param [Symbol] name
# @param [Hash] opts
def fetch_histogram(name, opts = {}, &block)
fetch_metric(:histogram, name, opts, &block)
end
# Fetch and/or initialize summary metric
# @param [Symbol] name
# @param [Hash] opts
def fetch_summary(name, opts = {}, &block)
fetch_metric(:summary, name, opts, &block)
end
# Define metric accessor method for a Counter
# @param [Symbol] name
# @param [Hash] opts
def define_counter(name, opts = {}, &block)
define_metric(:counter, name, opts, &block)
end
# Define metric accessor method for a Gauge
# @param [Symbol] name
# @param [Hash] opts
def define_gauge(name, opts = {}, &block)
define_metric(:gauge, name, opts, &block)
end
# Define metric accessor method for a Histogram
# @param [Symbol] name
# @param [Hash] opts
def define_histogram(name, opts = {}, &block)
define_metric(:histogram, name, opts, &block)
end
# Define metric accessor method for a Summary
# @param [Symbol] name
# @param [Hash] opts
def define_summary(name, opts = {}, &block)
define_metric(:summary, name, opts, &block)
end
end
end
end
end
|