Prometheus.ex

v3.0.5

Prometheus.ex v3.0.5 Prometheus.Metric.Boolean View Source

Boolean metric, to report booleans and flags.

Boolean is a non-standard metric that uses untyped metric underneath.

A Boolean is typically used as a flag i.e. enabled/disabled, online/offline.

Example:

-module(my_fuse_instrumenter).

-export([setup/0,
         fuse_event/2]).

 setup() ->
   prometheus_boolean:declare([{name, app_fuse_state},
                               {labels, [name]}, %% fuse name
                               {help, "State of various app fuses."}]),

 fuse_event(Fuse, Event) ->
   case Event of
     ok -> prometheus_boolean:set(app_fuse_state, [Fuse], true);
     blown -> prometheus_boolean:set(app_fuse_state, [Fuse], false);
     _ -> ok
   end.

Link to this section Summary

Functions

declare(spec)

Creates a boolean using spec. If a boolean with the same spec exists returns false

new(spec)

Creates a boolean using spec

remove(spec)

Removes boolean series identified by spec

reset(spec)

Resets the value of the boolean identified by spec

set(spec, value)

Sets the boolean identified by spec to value

toggle(spec)

Toggles the boolean identified by spec to value

value(spec)

Returns the value of the boolean identified by spec. If there is no boolean for given labels combination, returns :undefined

Link to this section Functions

Link to this function

declare(spec) View Source

Creates a boolean using spec. If a boolean with the same spec exists returns false.

Raises Prometheus.MissingMetricSpecKeyError if required spec key is missing.
Raises Prometheus.InvalidMetricNameError if metric name is invalid.
Raises Prometheus.InvalidMetricHelpError if help is invalid.
Raises Prometheus.InvalidMetricLabelsError if labels isn't a list.
Raises Prometheus.InvalidLabelNameError if label name is invalid.

Link to this function

new(spec) View Source

Creates a boolean using spec.

Raises Prometheus.MissingMetricSpecKeyError if required spec key is missing.
Raises Prometheus.InvalidMetricNameError if metric name is invalid.
Raises Prometheus.InvalidMetricHelpError if help is invalid.
Raises Prometheus.InvalidMetricLabelsError if labels isn't a list.
Raises Prometheus.InvalidLabelNameError if label name is invalid.
Raises Prometheus.MFAlreadyExistsError if a boolean with the same spec already exists.

Link to this function

remove(spec) View Source

Removes boolean series identified by spec.

Raises Prometheus.UnknownMetricError exception if a boolean for spec can't be found.
Raises Prometheus.InvalidMetricArityError exception if labels count mismatch.

Link to this function

reset(spec) View Source

Resets the value of the boolean identified by spec.

Raises Prometheus.UnknownMetricError exception if a boolean for spec can't be found.
Raises Prometheus.InvalidMetricArityError exception if labels count mismatch.

Link to this function

set(spec, value) View Source

Sets the boolean identified by spec to value.

Valid "truthy" values:

  • true;
  • false;
  • 0 -> false;
  • number > 0 -> true;
  • [] -> false
  • non-empty list -> true;
  • :undefined -> undefined

Other values will generate Prometheus.InvalidValueError error.

Raises Prometheus.InvalidValueError exception if value isn't a boolean or :undefined.
Raises Prometheus.UnknownMetricError exception if a boolean for spec can't be found.
Raises Prometheus.InvalidMetricArityError exception if labels count mismatch.

Link to this function

toggle(spec) View Source

Toggles the boolean identified by spec to value.

Raises Prometheus.InvalidValueError exception if boolean is :undefined.
Raises Prometheus.UnknownMetricError exception if a boolean for spec can't be found.
Raises Prometheus.InvalidMetricArityError exception if labels count mismatch.

Link to this function

value(spec) View Source

Returns the value of the boolean identified by spec. If there is no boolean for given labels combination, returns :undefined.

Raises Prometheus.UnknownMetricError exception if a boolean for spec can't be found.
Raises Prometheus.InvalidMetricArityError exception if labels count mismatch.