Packages
prometheus
0.2.0
6.1.3
6.1.2
6.1.1
6.1.0
6.0.3
6.0.2
6.0.1
6.0.0
5.1.1
5.1.0
5.0.0
4.13.0
retired
4.12.0
4.11.0
4.10.0
4.9.1
4.9.0
4.8.2
4.8.1
4.8.0
4.6.0
4.5.0
4.4.1
4.4.0
4.3.0
4.2.2
4.2.0
4.1.0
4.0.1
4.0.0
3.5.1
3.5.0
3.4.6
3.4.5
3.4.4
3.4.3
3.4.2
3.4.1
3.4.0
3.3.2
3.3.1
3.3.0
3.2.3
3.2.2
3.2.1
3.1.1
3.1.0
3.0.1
3.0.0
3.0.0-rc1
3.0.0-alpha9
3.0.0-alpha8
3.0.0-alpha7
3.0.0-alpha6
3.0.0-alpha5
3.0.0-alpha4
3.0.0-alpha3
3.0.0-alpha2
3.0.0-alpha10
3.0.0-alpha1
2.2.0
2.1.0
2.0.0
1.7.0
1.6.0
1.5.0
1.0.2
1.0.1
1.0.0
0.2.0
0.1.3
0.1.2
0.1.1
0.1.0
Prometheus.io client in Erlang
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Files
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Files
src/metrics/prometheus_gauge.erl
-module(prometheus_gauge).
%%% metric
-export([new/1,
new/2,
set/2,
set/3,
set/4,
reset/1,
reset/2,
reset/3,
value/1,
value/2,
value/3]).
%%% collector
-export([register/0,
register/1,
deregister/1,
collect_mf/2,
collect_metrics/3]).
-include("prometheus.hrl").
-behaviour(prometheus_collector).
-behaviour(prometheus_metric).
-define(TABLE, ?PROMETHEUS_GAUGE_TABLE).
-define(GAUGE_POS, 2).
%%====================================================================
%% Metric API
%%====================================================================
new(Spec) ->
new(Spec, default).
new(Spec, Registry) ->
{Name, Labels, Help} = prometheus_metric:extract_common_params(Spec),
%% Value = proplists:get_value(value, Spec),
register(Registry),
prometheus_metric:insert_mf(?TABLE, Registry, Name, Labels, Help).
set(Name, Value) ->
set(default, Name, [], Value).
set(Name, LabelValues, Value) ->
set(default, Name, LabelValues, Value).
set(Registry, Name, LabelValues, Value) when is_number(Value) ->
case ets:update_element(?TABLE, {Registry, Name, LabelValues}, {?GAUGE_POS, Value}) of
false ->
insert_metric(Registry, Name, LabelValues, Value, fun set/4);
true ->
ok
end,
ok;
set(_Registry, _Name, _LabelValues, Value) ->
erlang:error({invalid_value, Value, "set accepts only numbers"}).
reset(Name) ->
reset(default, Name, []).
reset(Name, LabelValues) ->
reset(default, Name, LabelValues).
reset(Registry, Name, LabelValues) ->
prometheus_metric:check_mf_exists(?TABLE, Registry, Name, LabelValues),
ets:update_element(?TABLE, {Registry, Name, LabelValues}, {?GAUGE_POS, 0}).
value(Name) ->
value(default, Name, []).
value(Name, LabelValues) ->
value(default, Name, LabelValues).
value(Registry, Name, LabelValues) ->
[{_Key, Value}] = ets:lookup(?TABLE, {Registry, Name, LabelValues}),
Value.
%%====================================================================
%% Collector API
%%====================================================================
register() ->
register(default).
register(Registry) ->
ok = prometheus_registry:register_collector(Registry, ?MODULE).
deregister(Registry) ->
prometheus_metric:deregister_mf(?TABLE, Registry),
ets:match_delete(?TABLE, {{Registry, '_', '_'}, '_'}).
collect_mf(Callback, Registry) ->
[Callback(gauge, Name, Labels, Help, [Registry]) ||
[Name, Labels, Help, _] <- prometheus_metric:metrics(?TABLE, Registry)].
collect_metrics(Name, Callback, [Registry]) ->
[Callback(LabelValues, Value) ||
[LabelValues, Value] <- ets:match(?TABLE, {{Registry, Name, '$1'}, '$2'})].
%%====================================================================
%% Private Parts
%%====================================================================
insert_metric(Registry, Name, LabelValues, Value, ConflictCB) ->
prometheus_metric:check_mf_exists(?TABLE, Registry, Name, LabelValues),
case ets:insert_new(?TABLE, {{Registry, Name, LabelValues}, Value}) of
false -> %% some sneaky process already inserted
ConflictCB(Registry, Name, LabelValues, Value);
true ->
ok
end.