ztracker

Configuration

Add the following to your composer.json:

```
"require": {
    "tricolor/ztracker": "~0.0.7.6"
},
"repositories": [
    {
        "type": "cvs",
        "url": "https://github.com/liubole/ztracker"
    }
],
```

Add the following to your "index.php"(or the entrance of request, both client and server):

```
global $trace_open;
$trace_open = class_exists('Tricolor\ZTracker\Core\GlobalTracer');
if ($trace_open) {
    // rabbitmq config
    \Tricolor\ZTracker\Config\Collector::rabbitConfig($trace_rabbitmq);
    // rate control
    \Tricolor\ZTracker\Config\Collector::$sampleRate = 5;
    // default output file: /tmp/biz-ztrace.log
    \Tricolor\ZTracker\Config\BizLogger::$output = '/tmp/trace_logs/biz-ztrace.log';
}
```

Usage

Client(index.php):

```
global $trace_open;
if ($trace_open) {
    try {
        $tracer = \Tricolor\ZTracker\Core\GlobalTracer::tracer();
        $tracer->newSpan()
            ->kind(Tricolor\ZTracker\Core\SpanKind\Server)
            ->shared(false);
        $tracer->currentSpan()->putTag('request_url', (string)$_SERVER['REQUEST_URI']);
        $tracer->log('get', $_GET);
        $tracer->log('post', $_POST);
        $tracer->log('server', $_SERVER);
    } catch (\Exception $e) {}
}
```

Server(index.php):

```
global $trace_open;
if ($trace_open) {
    try {
        $tracer = Tricolor\ZTracker\Core\GlobalTracer::tracer();
        $tracer->injector(Tricolor\ZTracker\Carrier\CarrierType\HttpHeader)->extract();
        $tracer->currentSpan()
            ->name(Tricolor\ZTracker\Common\Util::getServerApi())
            ->shared(true)
            ->kind(Tricolor\ZTracker\Core\SpanKind\Server);
        $tracer->log('get', $_GET);
        $tracer->log('post', $_POST);
        $tracer->log('server', $_SERVER);
    } catch (\Exception $e) {}
}
```

If we want to use it somewhere else, for example recording span of mysql server:

```
global $trace_open;
if ($trace_open) {
    $mysqlSpan = \Tricolor\ZTracker\Core\GlobalTracer::tracer()
        ->newChildSpan()->name('mysql.insert.user')
        ->shared(false)->kind(\Tricolor\ZTracker\Core\SpanKind\Client);
}
```

Publisher(RabbitMQ):

```
global $trace_open;
if ($trace_open && class_exists('\Tricolor\ZTracker\Core\GlobalTracer')) {
    try {
        $tracer = \Tricolor\ZTracker\Core\GlobalTracer::tracer();
        $tracer->newChildSpan()
            ->name($routing_key)
            ->shared(true)
            ->kind(\Tricolor\ZTracker\Core\SpanKind\Producer);
        $tracer->injector(\Tricolor\ZTracker\Carrier\CarrierType\RabbitMQHeader)
            ->inject($msg);
    } catch (\Exception $e) {
    }
}
```

Consumer(RabbitMQ):

```
global $trace_open;
$trace_open = class_exists('Tricolor\ZTracker\Core\GlobalTracer') && $file_path;
if ($trace_open) {
    try {
        \Tricolor\ZTracker\Config\Collector::rabbitConfig($trace_rabbitmq);
        \Tricolor\ZTracker\Config\BizLogger::$output = '/tmp/trace_logs/biz-ztrace.log';
        $tracer = \Tricolor\ZTracker\Core\GlobalTracer::tracer();
        $tracer->injector(\Tricolor\ZTracker\Carrier\CarrierType\RabbitMQHeader)->extract($msg);
        $tracer->currentSpan()
            ->name($routing_key)
            ->shared(true)
            ->kind(\Tricolor\ZTracker\Core\SpanKind\Consumer);
    } catch (\Exception $e) {
    }
}
```

Further reading

1. Google Dapper: https://research.google.com/archive/papers/dapper-2010-1.pdf
2. Zipkin: https://zipkin.io/
   GitHub - openzipkin/zipkin: https://github.com/openzipkin/zipkin
3. OpenTracing: http://opentracing.io/
   OpenTracing API · GitHub: https://github.com/opentracing