logi_prometheus
Prometheus metrics collector for logi.
logi_prometheus provides counters that count the number of log messages as follows:
logi_messages_total{logger="logger_name",severity="info",application="app_name",module="mod_name"} 1
It is useful for detecting anomalies of your application by using alerting rules.
Examples
Basic usage.
%% Installs `metrics_sink` to the default channel
> Sink = logi_prometheus_sink:new(metrics_sink, [{registry, example_registry}]).
> {ok, _} = logi_channel:install_sink(Sink, info).
%% Logs a message
> logi:info("foo").
%% Prints metrics
> io:format(prometheus_text_format:format(example_registry)).
# TYPE logi_messages_total counter
# HELP logi_messages_total Messages count
logi_messages_total{sink="metrics_sink",severity="info",application="stdlib",module="erl_eval"} 1By using prometheus_httpd, you can easily expose metrics collected by logi_prometheus_sink.
%% Installs `metrics_sink` to the default channel
> Sink = logi_prometheus_sink:new(metrics_sink).
> {ok, _} = logi_channel:install_sink(Sink, info).
%% Starts metrics exporter (i.e., HTTP server)
> prometheus_httpd:start().
%% Retrieves current metrics
> httpc:request("http://localhost:8081/metrics").
