Tags processor (#26)

* test processors

* add tag processors to inject tags at runtime

* manuall check version of tag processors

LICENSE.md

@@ -23,25 +23,3 @@ SOFTWARE.
 -- Software originally forked from:
 
 thephpleague/statsd - https://github.com/thephpleague/statsd
-
-The MIT License (MIT)
-
-Copyright (c) 2015 Harry Bragg <h.bragg@gmail.com>
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.

Makefile

@@ -50,7 +50,7 @@ lint-fix: ## Run phpcsf and fix possible lint errors.
 	${DOCKER_RUN} vendor/bin/phpcbf -p src/ tests/
 
 test-unit: ## Run the unit testsuite.
-	${DOCKER_RUN} vendor/bin/phpunit --colors=always --testsuite unit
+	${DOCKER_RUN} vendor/bin/phpunit --colors=always --testsuite unit --stop-on-failure
 
 test-integration: ## Run the integration testsuite
 	${MAKE} test-echo

README.md

@@ -119,6 +119,17 @@ $statsd->set('api.unique_logins', $userID, ['tag']);
 $statsd->timing('api.response_time', 245, ['end-point' => 'page', 'env' => 'test']);
 ```
 
+##### Tags Processors
+
+You can add tag processors to inject tags at runtime for each metric.
+
+```php
+$statsd->addTagProcessor(function (array $tags) {
+    $tags['new-key'] = 'new-value';
+    return $tags;
+});
+```
+
 #### Events
 
 ```php

src/Client.php

@@ -160,6 +160,13 @@ class Client
      */
     protected $tags = [];
 
+    /**
+     * List of tags processors to apply to every metric being sent out
+     *
+     * @var callable[]
+     */
+    protected $tagProcessors = [];
+
     /**
      * Singleton Reference
      *
@@ -224,6 +231,7 @@ public function __toString()
      *                       :onError <enum[error,exception,ignore]> - What we should do on error
      *                       :dataDog <bool> - Use DataDog's version of statsd (Default: true)
      *                       :tags <array> - List of tags to add to each message
+     *                       :tagProcessors <array> - List of tags processors to use
      *
      * @return Client This instance
      * @throws ConfigurationException If port is invalid
@@ -252,6 +260,15 @@ public function configure(array $options = [])
         $setOption('dataDog', 'boolean');
         $setOption('tags', 'array');
 
+        if (isset($options['tagProcessors']) && is_array($options['tagProcessors'])) {
+            foreach ($options['tagProcessors'] as $tagProcessor) {
+                if (!is_callable($tagProcessor)) {
+                    throw new ConfigurationException($this->instanceId, 'supplied tag processor is not a callable');
+                }
+                $this->addTagProcessor($tagProcessor);
+            }
+        }
+
         $this->port = (int) $this->port;
         if (!$this->port || !is_numeric($this->port) || $this->port > 65535) {
             throw new ConfigurationException($this->instanceId, 'Option: Port is invalid or is out of range');
@@ -270,6 +287,17 @@ public function configure(array $options = [])
         return $this;
     }
 
+    /**
+     * @param callable $tagsProcessor
+     *
+     * @return Client
+     */
+    public function addTagProcessor(callable $tagsProcessor)
+    {
+        $this->tagProcessors[] = $tagsProcessor;
+        return $this;
+    }
+
     /**
      * Get Host
      *
@@ -593,7 +621,7 @@ protected function send(array $data, array $tags = [])
     {
         $messages = [];
         $prefix = $this->namespace ? $this->namespace . '.' : '';
-        $formattedTags = $this->formatTags(array_merge($this->tags, $tags));
+        $formattedTags = $this->formatTags($this->processTags(array_merge($this->tags, $tags)));
         foreach ($data as $key => $value) {
             $messages[] = $prefix . $key . ':' . $value . $formattedTags;
         }
@@ -622,4 +650,19 @@ protected function sendMessages(array $messages)
 
         return $this;
     }
+
+    /**
+     * Process a set of tags with some user defined processes to add custom runtime data
+     *
+     * @param array $tags
+     *
+     * @return array|mixed
+     */
+    private function processTags(array $tags)
+    {
+        foreach ($this->tagProcessors as $tagProcessor) {
+            $tags = call_user_func($tagProcessor, $tags);
+        }
+        return $tags;
+    }
 }

tests/unit/ConfigurationTest.php

@@ -13,7 +13,6 @@
 
 namespace Graze\DogStatsD\Test\Unit;
 
-use Graze\DogStatsD\Exception\ConfigurationException;
 use Graze\DogStatsD\Test\TestCase;
 
 class ConfigurationTest extends TestCase
@@ -138,4 +137,26 @@ public function testOnErrorConfiguration()
         $this->client->configure(['onError' => 'ignore']);
         $this->assertAttributeEquals('ignore', 'onError', $this->client);
     }
+
+    public function testTagsProcessorAcceptsCallable()
+    {
+        $processor = function (array $tags) {
+            return $tags;
+        };
+        $this->client->configure([
+            'tagProcessors' => [$processor],
+        ]);
+        $this->assertAttributeEquals([$processor], 'tagProcessors', $this->client);
+    }
+
+    /**
+     * @expectedException \Graze\DogStatsD\Exception\ConfigurationException
+     * @expectedExceptionMessage supplied tag processor is not a callable
+     */
+    public function testTagsProcessorDoesNotAcceptOtherThings()
+    {
+        $this->client->configure([
+            'tagProcessors' => ['a string']
+        ]);
+    }
 }

tests/unit/TagProcessorTest.php

@@ -0,0 +1,48 @@
+<?php
+/**
+ * This file is part of graze/dog-statsd
+ *
+ * Copyright (c) 2016 Nature Delivered Ltd. <https://www.graze.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ * @license https://github.com/graze/dog-statsd/blob/master/LICENSE.md
+ * @link    https://github.com/graze/dog-statsd
+ */
+
+namespace Graze\DogStatsD\Test\Unit;
+
+use Graze\DogStatsD\Test\TestCase;
+
+class TagProcessorTest extends TestCase
+{
+    public function testSingleProcessor()
+    {
+        $this->client->addTagProcessor(function (array $tags) {
+            $tags['custom'] = 1;
+            return $tags;
+        });
+        $this->client->increment('test_metric', 1, 1, ['tag']);
+        $this->assertEquals('test_metric:1|c|#tag,custom:1', $this->client->getLastMessage());
+    }
+
+    public function testMultipleProcessors()
+    {
+        $this->client->addTagProcessor(function (array $tags) {
+            $tags['custom'] = 1;
+            return $tags;
+        });
+        $this->client->addTagProcessor(function (array $tags) {
+            $this->assertArrayHasKey(
+                'custom',
+                $tags,
+                'ensure that the processors get processed in the order they are attached to the client'
+            );
+            $tags['second'] = 2;
+            return $tags;
+        });
+        $this->client->increment('test_metric', 1, 1, ['tag' => 'value']);
+        $this->assertEquals('test_metric:1|c|#tag:value,custom:1,second:2', $this->client->getLastMessage());
+    }
+}