/ 
Measure-Everything-1.003
River stage one • 4 direct dependents • 4 total dependents
/ Measure::Everything

NAME

Measure::Everything - Log::Any for Stats

VERSION

version 1.003

SYNOPSIS

In a module where you want to count some stats:

package Foo;
use Measure::Everything qw($stats);

$stats->write('jigawats', 1.21, { source=>'Plutonium', location=>'Hill Valley' });

In your application:

use Foo;
use Measure::Everything::Adapter;
Measure::Everything::Adapter->set('InfluxDB::File', %args);

DESCRIPTION

Measure::Everything tries to provide a standard measuring API for modules (like Log::Any does for logging). Measure::Everything::Adapters allow applications to choose the mechanism for measuring stats (for example InfluxDB, OpenTSDB, Graphite, etc).

For now, Measure::Everything only supports InfluxDB, because that's what we're using. But I hope that other time series databases (or other storage backends) can be added to Measure::Everything. Unfortunately, measuring stats is not such a well-established domain like logging (where we have a set of common log levels, and basically "just" need to pass some string to some logging sink). So it is very likely that Measure::Everything cannot provide a generic API, where you can switch out Adapters without changing the measuring code. But we can try!

Measure::Everything currently provides a way to access a global object $stats, on which you can call the write method. The currently active Adapter decides what to do with the data passed to write. In contrast to Log::Any, there can be only one active Adapter.

PRODUCING STATS (FOR MODULES)

Getting a stats handler

use Measure::Everything qw($stats);

This will import a $stats object into your current namespace. What this object will do depends on the active Adapter (see section CONSUMING STATS)

Counting

For now, Measure::Everything provides one method to write stats, write:

$stats->write($measurement, $value | \%values, \%tags?, $timestamp?);

It is still a bit uncertain whether this API will work for all possible time series databases and other storage backends. But it works for InfluxDB!

$measurement is the name of the thing you want to count.

$value or \%values is the value you want to count. Not all databases can handle multiple values. In this case it should be the job of the Adapter to convert the hashref of values into something the storage backend can handle.

\%tags is a hashref of further tags. InfluxDB uses them, not sure about other systems.

$timestamp is the time of the measurement. In general you should not pass a timestamp and instead let the Adapter figure out the current time and format it in a way the backend can understand. But if you want to record stats for past (or future?) events, you will need to pass in the timestamp in the correct format (or hope that the Adapter will convert it for you).

CONSUMING STATS (FOR APPLICATIONS)

Application here means the script running your modules. Could be a daemon, a cron-job, a command line script, whatever. In this script you will have to define what to do with stats generated in your modules. You could throw them away (by using Measure::Everything::Adapter::Null), which is the default. Or you define an adapter, that will handle the data passed via write.

use Measure::Everything::Adapter;
Measure::Everything::Adapter->set('InfluxDB::File', file => '/tmp/my_app.stats');

TODO

  • tests

  • docs

  • Measure::Everything::Adapter::Memory

  • Measure::Everything::Adapter::Test

  • more InfluxDB Adapters: Direct, ZeroMQ, UDP, ..

  • move Measure::Everything::Adapter::InfluxDB::* into seperate distribution(s)

SEE ALSO

The basic concept is stolen from <Log::Any|https://metacpan.org/pod/Log::Any>. If you have troubles understanding this set of modules, please read the excellent Log::Any docs, and substitue "logging" with "writing stats".

For more information on measuring & stats, and the obvious inspiration for this module's name, read the interesting article Measure Anything, Measure Everything by Ian Malpass from Etsy.

THANKS

Thanks to

  • validad.com for funding the development of this code.

AUTHOR

Thomas Klausner <domm@plix.at>

COPYRIGHT AND LICENSE

This software is copyright (c) 2015 - 2021 by Thomas Klausner.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.