Dev ❤️ Ops

Areas

• Producing 👈
• Collecting/Forwarding
• Storing
• Analysing

<?php
 
$logger->logf('saving user %s failed: %s', $username, $err);
// saving user john.doe failed: cannot connect to database

everything is very goooood
everything is very goooood
everything is very goooood
everything is very goooood
everything is very goooood
everything is very goooood
cannot connect to database
everything is very goooood
everything is very goooood
everything is very goooood
everything is very goooood

everything is very goooood
everything is very goooood
everything is very goooood
everything is very goooood
everything is very goooood
everything is very goooood
cannot connect to database
everything is very goooood
everything is very goooood
everything is very goooood
everything is very goooood

Leveled logging

<?php
 
$logger->errorf('saving user %s failed: %s', $username, $err);
// [ERROR] saving user john.doe failed: cannot connect to database

Usual levels

• (trace)
• debug
• info
• warn
• error

Structured logging

<?php
 
$logger->error(
    'saving user failed',
    [
        'user' => $username,
        'reason' => $err,
    ]
);
// [ERROR] saving user failed
//      user: john.doe
//      reason: cannot connect to database

Correlation ID

• Identifies a request
• Connects log events from the same request
• Works across services
• PHP: shared-nothing architecture 🚀

Other considerations: GDPR

<?php
 
// 👎 DON'T!!!
$logger->error('saving user failed',
    [
        'ip' => $ip,
        'credit_card' => $creditCard,
    ]
);
 
// 👍 DO!
$logger->error('saving user failed', ['user_id' => $userId]);

Other considerations: Logging is expensive!

<?php
 
// 👎 DON'T!!!
for ($i=0; $i < 100; $i++) {
    $logger->info('processing details', ['id' => $i]);
}
 
// 👍 DO!
$logger->info('starting batch processing', ['items' => 100]);
for ($i=0; $i < 100; $i++) {
    // if error
    $logger->error('failed to process item', ['id' => $i]);
}
$logger->info('finished batch processing', ['errors' => 1]);

Logging in PHP

• PSR-3
• Monolog

Measure everything!!!

...but start with

• USE
• RED

Telemetry models

• push: emit metrics to an external system (eg. Graphite, Statsd)
• pull: expose metrics at some known location (eg. Prometheus)

(PHP: shared-nothing architecture 💩)

Prometheus

• Pushgateway
• Redis collector

Alerting

• Alert user facing services first
• Avoid alert fatigue 😴

Correlation ID on steroids

https://github.com/census-instrumentation/opencensus-php

<?php
 
// Creates a detached span
$span = Tracer::startSpan(['name' => 'expensive-operation']);
 
// Opens a scope that attaches the span to the current context
$scope = Tracer::withSpan($span);
try {
    $pi = calculatePi(1000);
} finally {
    // Closes the scope (ends the span)
    $scope->close();
}

PHP: shared-nothing architecture 🚀