When i use Datadog to collect tracer/span in our PHP , i realize that Datadog library does not collect the client IP address. I don’t know what the reason behind this, but not having the client IP is very hard to troubleshoot the issue. After a while i figured out the way to hack the code. The hack is to modify this file /opt/datadog-php/dd-trace-sources/bridge/_generated.php
This is my modification – check the line #================My Customize code
private static function initRootSpan(Tracer $tracer)
{
$options = array('start_time' => Time::now());
if ('cli' === PHP_SAPI) {
$operationName = isset($_SERVER['argv'][0]) ? basename($_SERVER['argv'][0]) : 'cli.command';
$span = $tracer->startRootSpan($operationName, StartSpanOptions::create($options))->getSpan();
$span->setTag(Tag::SPAN_TYPE, Type::CLI);
} else {
$operationName = 'web.request';
$span = $tracer->startRootSpan($operationName, StartSpanOptionsFactory::createForWebRequest($tracer, $options, Request::getHeaders()))->getSpan();
$span->setTag(Tag::SPAN_TYPE, Type::WEB_SERVLET);
if (isset($_SERVER['REQUEST_METHOD'])) {
$span->setTag(Tag::HTTP_METHOD, $_SERVER['REQUEST_METHOD']);
}
if (isset($_SERVER['REQUEST_URI'])) {
$span->setTag(Tag::HTTP_URL, $_SERVER['REQUEST_URI']);
}
#================My Customize code
if (isset($_SERVER['REMOTE_ADDR'])) {
$span->setTag("http.client_ip", $_SERVER['REMOTE_ADDR']);
}
if (isset($_SERVER['SCRIPT_NAME'])) {
$span->setTag("http.script_name", $_SERVER['SCRIPT_NAME']);
}
if (isset($_SERVER['HTTP_USER_AGENT'])) {
$span->setTag("http.user_agent", $_SERVER['HTTP_USER_AGENT']);
}
if (isset($_SERVER['X-Forwarded-For'])) {
$span->setTag("http.real_client_ip", $_SERVER['X-Forwarded-For']);
}
#================End of My Customize code
$span->setTag(Tag::HTTP_STATUS_CODE, 200);