Merge pull request #5 from whitemerry/#4.-Adding-http-option

SimpleHttpLogger

Author: whitemerry

README.md

@@ -26,11 +26,13 @@ $endpoint = new Endpoint(
     '80' // Current application port (default 80)
 );
 ```
-Next, define storage for traces - now implemented is only one, but you can implement own using our interface, FileLogger (Scroll below for more information about loggers in php):
+Next, define storage for traces - currently two types are supported - SimpleHttpLogger and FileLogger,
+SimpleHttpLogger automatically sends trace data to Zipkin's service,
+FileLogger (you can read more about this logger below) sends trace data to file, then you need to write curl for uploading this data to Zipkin's
+(of course you can implement own using our interface):
 ```php
-$logger = new FileLogger([
-    'path' => './logs', // Zipkin traces logs location
-    'fileName' => 'zipkin.log' // File name
+$logger = new SimpleHttpLogger([
+    'host' => 'http://192.168.33.11:9411' // Zipkin's API host with schema (http://) and without trailing slash
 ]);
 ```
 ***Now you can initialize Tracer!***
@@ -66,7 +68,7 @@ As last step just trigger trace method from $tracer, for example in shutdown eve
 ```php
 $tracer->trace();
 ```
-Now as you can see, requests to your website are generating new lines in logs/zipkin.log
+Now as you can see, you have new entries in the Zipkin's UI! :)
 
 #### Adding spans to trace
 As you already now, in Zipkin, you can store and visualize communication between 2 services (for example databases, microservices). 
@@ -131,15 +133,26 @@ TracerInfo::isSampled(); // Sampled - X-B3-Sampled
 ```
 Remember to set this headers to request in your client to other services.
 
-#### Why FileLogger?
+#### Why do i prefer FileLogger?
 You can write your own logger. I prefer this type, because optimization.
-It's better to send logs to Zipkin in background than increasing page load time by sending next request to API. 
+It's better to store logs in files and send to Zipkin in background than increasing page load time by sending next request to API. 
 
 Don't let your users wait :)
 
+Usage example:
+```php
+$logger = new FileLogger([
+    'path' => './logs', // Zipkin traces logs location
+    'fileName' => 'zipkin.log' // File name
+]);
+```
+
 #### How can i upload logs to Zipkin?
-Use Zipkin's rest API and send traces from zipkin.log.
+For SimpleHttpLogger:
+It does eveything for you.
 
+For FileLogger:
+Use Zipkin's rest API and send traces from zipkin.log.
 How do i do that? Cron every 10 minutes, calling action witch sends POST.
 
 You can read more about Zipkin's API endpoint [here](http://zipkin.io/zipkin-api/#/paths/%252Fspans/post)

src/Logger/FileLogger.php

@@ -35,7 +35,7 @@ public function __construct($options = [])
         $this->options = array_merge($defaults, $options);
 
         if (!is_dir($this->options['path'])) {
-            throw new \BadMethodCallException('Invalid logs directory');
+            throw new LoggerException('Invalid logs directory');
         }
     }
 

src/Logger/LoggerException.php

@@ -0,0 +1,10 @@
+<?php
+namespace whitemerry\phpkin\Logger;
+
+/**
+ * Class LoggerException for try-catch blocks
+ *
+ * @author Piotr Bugaj <[email protected]>
+ * @package whitemerry\phpkin\Logger
+ */
+class LoggerException extends \Exception {}

src/Logger/SimpleHttpLogger.php

@@ -0,0 +1,82 @@
+<?php
+namespace whitemerry\phpkin\Logger;
+
+/**
+ * Class SimpleHttpLogger
+ *
+ * @author Piotr Bugaj <[email protected]>
+ * @package whitemerry\phpkin\Logger
+ */
+class SimpleHttpLogger implements Logger
+{
+    /**
+     * @var array
+     */
+    protected $options;
+
+    /**
+     * @inheritdoc
+     *
+     * $options
+     *      ['host'] string Zipkin's host with port, schema and without trailing slash (default http://127.0.0.1:9411)
+     *      ['endpoint'] string Zipkin's endpoint (default /api/v1/spans)
+     *      ['muteErrors'] bool Mute exceptions on upload error (default true)
+     *      ['contextOptions'] array More options for stream_context_create like ssl
+     *
+     * @param $options array See above
+     *
+     * @throws \BadMethodCallException
+     */
+    public function __construct($options = [])
+    {
+        $defaults = [
+            'host' => 'http://127.0.0.1:9144',
+            'endpoint' => '/api/v1/spans',
+            'muteErrors' => true,
+            'contextOptions' => []
+        ];
+
+        $this->options = array_merge($defaults, $options);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function trace($spans)
+    {
+        $contextOptions = [
+            'http' => [
+                'method' => 'POST',
+                'header' => 'Content-type: application/json',
+                'content' => json_encode($spans),
+                'ignore_errors' => true
+            ]
+        ];
+        $context = stream_context_create(array_merge_recursive($contextOptions, $this->options['contextOptions']));
+        @file_get_contents($this->options['host'] . $this->options['endpoint'], false, $context);
+
+        if (!$this->options['muteErrors'] && !$this->validResponse($http_response_header)) {
+            throw new LoggerException('Trace upload failed');
+        }
+    }
+
+    /**
+     * Search for 202 header
+     *
+     * @return bool
+     */
+    protected function validResponse($headers)
+    {
+        if (empty($headers)) {
+            return false;
+        }
+
+        foreach ($headers as $header) {
+            if (preg_match('/202/', $header)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}