From 69cf0607404f943845318c8f4b43c01f369ec725 Mon Sep 17 00:00:00 2001
From: Sergey Protko <fesors@gmail.com>
Date: Mon, 18 Sep 2017 17:43:47 +0300
Subject: [PATCH 1/3] Add Predis support

---
 composer.json                                 |   6 +-
 examples/flush_adapter.php                    |   5 +
 examples/metrics.php                          |   4 +
 examples/pushgateway.php                      |   4 +
 examples/some_counter.php                     |   4 +
 examples/some_gauge.php                       |   4 +
 examples/some_histogram.php                   |   4 +
 src/Prometheus/PushGateway.php                |   4 +-
 src/Prometheus/Storage/Predis.php             | 335 ++++++++++++++++++
 tests/Test/BlackBoxPushGatewayTest.php        |   2 +-
 .../Predis/CollectorRegistryTest.php          |  16 +
 tests/Test/Prometheus/Predis/CounterTest.php  |  20 ++
 tests/Test/Prometheus/Predis/GaugeTest.php    |  20 ++
 .../Test/Prometheus/Predis/HistogramTest.php  |  20 ++
 14 files changed, 443 insertions(+), 5 deletions(-)
 create mode 100644 src/Prometheus/Storage/Predis.php
 create mode 100644 tests/Test/Prometheus/Predis/CollectorRegistryTest.php
 create mode 100644 tests/Test/Prometheus/Predis/CounterTest.php
 create mode 100644 tests/Test/Prometheus/Predis/GaugeTest.php
 create mode 100644 tests/Test/Prometheus/Predis/HistogramTest.php

diff --git a/composer.json b/composer.json
index 3d97c12..1126c79 100644
--- a/composer.json
+++ b/composer.json
@@ -15,11 +15,13 @@
         "guzzlehttp/guzzle": "^6.2"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.1.0"
+        "phpunit/phpunit": "4.1.0",
+        "predis/predis": "^1.1"
     },
     "suggest": {
         "ext-redis": "Required if using Redis.",
-        "ext-apc": "Required if using APCu."
+        "predis/predis": "Required if using Predis",
+        "ext-apcu": "Required if using APCu."
     },
     "autoload": {
         "psr-0": {
diff --git a/examples/flush_adapter.php b/examples/flush_adapter.php
index 0c3862d..a2f98c0 100644
--- a/examples/flush_adapter.php
+++ b/examples/flush_adapter.php
@@ -8,6 +8,11 @@
 
     $redisAdapter = new Prometheus\Storage\Redis(array('host' => REDIS_HOST));
     $redisAdapter->flushRedis();
+} elseif ($adapter === 'predis') {
+    $adapter = new Prometheus\Storage\Predis([
+        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
+    ]);
+    $adapter->flushRedis();
 } elseif ($adapter === 'apc') {
     $apcAdapter = new Prometheus\Storage\APC();
     $apcAdapter->flushAPC();
diff --git a/examples/metrics.php b/examples/metrics.php
index fa89247..76c834a 100644
--- a/examples/metrics.php
+++ b/examples/metrics.php
@@ -11,6 +11,10 @@
 if ($adapter === 'redis') {
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
+} elseif ($adapter === 'predis') {
+    $adapter = new Prometheus\Storage\Predis([
+        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
+    ]);
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/examples/pushgateway.php b/examples/pushgateway.php
index 984035d..6c4d789 100644
--- a/examples/pushgateway.php
+++ b/examples/pushgateway.php
@@ -9,6 +9,10 @@
 if ($adapter === 'redis') {
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
+} elseif ($adapter === 'predis') {
+    $adapter = new Prometheus\Storage\Predis([
+        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
+    ]);
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/examples/some_counter.php b/examples/some_counter.php
index 823bfac..58fc6ff 100644
--- a/examples/some_counter.php
+++ b/examples/some_counter.php
@@ -10,6 +10,10 @@
 if ($adapter === 'redis') {
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
+} elseif ($adapter === 'predis') {
+    $adapter = new Prometheus\Storage\Predis([
+        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
+    ]);
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/examples/some_gauge.php b/examples/some_gauge.php
index b3e2382..b847131 100644
--- a/examples/some_gauge.php
+++ b/examples/some_gauge.php
@@ -13,6 +13,10 @@
 if ($adapter === 'redis') {
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
+} elseif ($adapter === 'predis') {
+    $adapter = new Prometheus\Storage\Predis([
+        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
+    ]);
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/examples/some_histogram.php b/examples/some_histogram.php
index 6b34809..a618cbe 100644
--- a/examples/some_histogram.php
+++ b/examples/some_histogram.php
@@ -12,6 +12,10 @@
 if ($adapter === 'redis') {
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
+} elseif ($adapter === 'predis') {
+    $adapter = new Prometheus\Storage\Predis([
+        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
+    ]);
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/src/Prometheus/PushGateway.php b/src/Prometheus/PushGateway.php
index a4a3fd2..8cbbac7 100644
--- a/src/Prometheus/PushGateway.php
+++ b/src/Prometheus/PushGateway.php
@@ -49,9 +49,9 @@ public function pushAdd(CollectorRegistry $collectorRegistry, $job, $groupingKey
      * @param $job
      * @param $groupingKey
      */
-    public function delete($job, $groupingKey = null)
+    public function delete(CollectorRegistry $collectorRegistry, $job, $groupingKey = null)
     {
-        $this->doRequest(null, $job, $groupingKey, 'delete');
+        $this->doRequest($collectorRegistry, $job, $groupingKey, 'delete');
     }
 
     /**
diff --git a/src/Prometheus/Storage/Predis.php b/src/Prometheus/Storage/Predis.php
new file mode 100644
index 0000000..d4a3258
--- /dev/null
+++ b/src/Prometheus/Storage/Predis.php
@@ -0,0 +1,335 @@
+<?php
+
+namespace Prometheus\Storage;
+
+use Predis\Client;
+use Prometheus\Counter;
+use Prometheus\Exception\StorageException;
+use Prometheus\Gauge;
+use Prometheus\Histogram;
+use Prometheus\MetricFamilySamples;
+
+class Predis implements Adapter
+{
+    const PROMETHEUS_METRIC_KEYS_SUFFIX = '_METRIC_KEYS';
+
+    private static $defaultOptions = [
+        'host' => '127.0.0.1',
+        'port' => 6379,
+        'timeout' => 0.1,
+        'read_timeout' => 10,
+        'persistent_connections' => false,
+    ];
+
+    private static $prefix = 'PROMETHEUS_';
+
+    private $options;
+    /**
+     * @var Client
+     */
+    private $predis;
+
+    public function __construct(array $options = array())
+    {
+        $this->options = array_merge(self::$defaultOptions, $options);
+    }
+
+    /**
+     * @param array $options
+     */
+    public static function setDefaultOptions(array $options)
+    {
+        self::$defaultOptions = array_merge(self::$defaultOptions, $options);
+    }
+
+    public static function setPrefix($prefix)
+    {
+        self::$prefix = $prefix;
+    }
+
+    public function flushRedis()
+    {
+        $this->openConnection();
+        $this->predis->flushall();
+    }
+
+    /**
+     * @return MetricFamilySamples[]
+     * @throws StorageException
+     */
+    public function collect()
+    {
+        $this->openConnection();
+        $metrics = $this->collectHistograms();
+        $metrics = array_merge($metrics, $this->collectGauges());
+        $metrics = array_merge($metrics, $this->collectCounters());
+        return array_map(
+            function (array $metric) {
+                return new MetricFamilySamples($metric);
+            },
+            $metrics
+        );
+    }
+
+    /**
+     * @throws StorageException
+     */
+    private function openConnection()
+    {
+        try {
+
+            $this->predis = new Client([
+                'scheme' => 'tcp',
+                'host'   => $this->options['host'],
+                'port'   => $this->options['port'],
+                'timeout' => $this->options['timeout'],
+                'read_write_timeout' => $this->options['read_timeout'],
+                'persistent' => $this->options['persistent_connections'],
+            ]);
+
+        } catch (\RedisException $e) {
+            throw new StorageException("Can't connect to Redis server", 0, $e);
+        }
+    }
+
+    public function updateHistogram(array $data)
+    {
+        $this->openConnection();
+        $bucketToIncrease = '+Inf';
+        foreach ($data['buckets'] as $bucket) {
+            if ($data['value'] <= $bucket) {
+                $bucketToIncrease = $bucket;
+                break;
+            }
+        }
+        $metaData = $data;
+        unset($metaData['value']);
+        unset($metaData['labelValues']);
+        $this->predis->eval(<<<LUA
+local increment = redis.call('hIncrByFloat', KEYS[1], KEYS[2], ARGV[1])
+redis.call('hIncrBy', KEYS[1], KEYS[3], 1)
+if increment == ARGV[1] then
+    redis.call('hSet', KEYS[1], '__meta', ARGV[2])
+    redis.call('sAdd', KEYS[4], KEYS[1])
+end
+LUA
+            ,
+            4,
+            $this->toMetricKey($data),
+            json_encode(array('b' => 'sum', 'labelValues' => $data['labelValues'])),
+            json_encode(array('b' => $bucketToIncrease, 'labelValues' => $data['labelValues'])),
+            self::$prefix . Histogram::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
+            $data['value'],
+            json_encode($metaData)
+        );
+    }
+
+    public function updateGauge(array $data)
+    {
+        $this->openConnection();
+        $metaData = $data;
+        unset($metaData['value']);
+        unset($metaData['labelValues']);
+        unset($metaData['command']);
+        $this->predis->eval(<<<LUA
+local result = redis.call(KEYS[2], KEYS[1], KEYS[4], ARGV[1])
+
+if KEYS[2] == 'hSet' then
+    if result == 1 then
+        redis.call('hSet', KEYS[1], '__meta', ARGV[2])
+        redis.call('sAdd', KEYS[3], KEYS[1])
+    end
+else
+    if result == ARGV[1] then
+        redis.call('hSet', KEYS[1], '__meta', ARGV[2])
+        redis.call('sAdd', KEYS[3], KEYS[1])
+    end
+end
+LUA
+            ,
+            4,
+            $this->toMetricKey($data),
+            $this->getRedisCommand($data['command']),
+            self::$prefix . Gauge::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
+            json_encode($data['labelValues']),
+            $data['value'],
+            json_encode($metaData)
+        );
+    }
+
+    public function updateCounter(array $data)
+    {
+        $this->openConnection();
+        $metaData = $data;
+        unset($metaData['value']);
+        unset($metaData['labelValues']);
+        unset($metaData['command']);
+        $result = $this->predis->eval(<<<LUA
+local result = redis.call(KEYS[2], KEYS[1], KEYS[4], ARGV[1])
+if result == tonumber(ARGV[1]) then
+    redis.call('hMSet', KEYS[1], '__meta', ARGV[2])
+    redis.call('sAdd', KEYS[3], KEYS[1])
+end
+return result
+LUA
+            ,
+            4,
+            $this->toMetricKey($data),
+            $this->getRedisCommand($data['command']),
+            self::$prefix . Counter::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
+            json_encode($data['labelValues']),
+            $data['value'],
+            json_encode($metaData)
+        );
+        return $result;
+    }
+
+    private function collectHistograms()
+    {
+        $keys = $this->predis->smembers(self::$prefix . Histogram::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
+        sort($keys);
+        $histograms = array();
+        foreach ($keys as $key) {
+            $raw = $this->predis->hgetall($key);
+            $histogram = json_decode($raw['__meta'], true);
+            unset($raw['__meta']);
+            $histogram['samples'] = array();
+
+            // Add the Inf bucket so we can compute it later on
+            $histogram['buckets'][] = '+Inf';
+
+            $allLabelValues = array();
+            foreach (array_keys($raw) as $k) {
+                $d = json_decode($k, true);
+                if ($d['b'] == 'sum') {
+                    continue;
+                }
+                $allLabelValues[] = $d['labelValues'];
+            }
+
+            // We need set semantics.
+            // This is the equivalent of array_unique but for arrays of arrays.
+            $allLabelValues = array_map("unserialize", array_unique(array_map("serialize", $allLabelValues)));
+            sort($allLabelValues);
+
+            foreach ($allLabelValues as $labelValues) {
+                // Fill up all buckets.
+                // If the bucket doesn't exist fill in values from
+                // the previous one.
+                $acc = 0;
+                foreach ($histogram['buckets'] as $bucket) {
+                    $bucketKey = json_encode(array('b' => $bucket, 'labelValues' => $labelValues));
+                    if (!isset($raw[$bucketKey])) {
+                        $histogram['samples'][] = array(
+                            'name' => $histogram['name'] . '_bucket',
+                            'labelNames' => array('le'),
+                            'labelValues' => array_merge($labelValues, array($bucket)),
+                            'value' => $acc
+                        );
+                    } else {
+                        $acc += $raw[$bucketKey];
+                        $histogram['samples'][] = array(
+                            'name' => $histogram['name'] . '_bucket',
+                            'labelNames' => array('le'),
+                            'labelValues' => array_merge($labelValues, array($bucket)),
+                            'value' => $acc
+                        );
+                    }
+                }
+
+                // Add the count
+                $histogram['samples'][] = array(
+                    'name' => $histogram['name'] . '_count',
+                    'labelNames' => array(),
+                    'labelValues' => $labelValues,
+                    'value' => $acc
+                );
+
+                // Add the sum
+                $histogram['samples'][] = array(
+                    'name' => $histogram['name'] . '_sum',
+                    'labelNames' => array(),
+                    'labelValues' => $labelValues,
+                    'value' => $raw[json_encode(array('b' => 'sum', 'labelValues' => $labelValues))]
+                );
+            }
+            $histograms[] = $histogram;
+        }
+        return $histograms;
+    }
+
+    private function collectGauges()
+    {
+        $keys = $this->predis->smembers(self::$prefix . Gauge::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
+        sort($keys);
+        $gauges = array();
+        foreach ($keys as $key) {
+            $raw = $this->predis->hgetall($key);
+            $gauge = json_decode($raw['__meta'], true);
+            unset($raw['__meta']);
+            $gauge['samples'] = array();
+            foreach ($raw as $k => $value) {
+                $gauge['samples'][] = array(
+                    'name' => $gauge['name'],
+                    'labelNames' => array(),
+                    'labelValues' => json_decode($k, true),
+                    'value' => $value
+                );
+            }
+            usort($gauge['samples'], function($a, $b){
+                return strcmp(implode("", $a['labelValues']), implode("", $b['labelValues']));
+            });
+            $gauges[] = $gauge;
+        }
+        return $gauges;
+    }
+
+    private function collectCounters()
+    {
+        $keys = $this->predis->smembers(self::$prefix . Counter::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
+        sort($keys);
+        $counters = array();
+        foreach ($keys as $key) {
+            $raw = $this->predis->hgetall($key);
+            $counter = json_decode($raw['__meta'], true);
+            unset($raw['__meta']);
+            $counter['samples'] = array();
+            foreach ($raw as $k => $value) {
+                $counter['samples'][] = array(
+                    'name' => $counter['name'],
+                    'labelNames' => array(),
+                    'labelValues' => json_decode($k, true),
+                    'value' => $value
+                );
+            }
+            usort($counter['samples'], function($a, $b){
+                return strcmp(implode("", $a['labelValues']), implode("", $b['labelValues']));
+            });
+            $counters[] = $counter;
+        }
+        return $counters;
+    }
+
+    private function getRedisCommand($cmd)
+    {
+        switch ($cmd) {
+            case Adapter::COMMAND_INCREMENT_INTEGER:
+                return 'hIncrBy';
+            case Adapter::COMMAND_INCREMENT_FLOAT:
+                return 'hIncrByFloat';
+            case Adapter::COMMAND_SET:
+                return 'hSet';
+            default:
+                throw new \InvalidArgumentException("Unknown command");
+        }
+    }
+
+    /**
+     * @param array $data
+     * @return string
+     */
+    private function toMetricKey(array $data)
+    {
+        return implode(':', array(self::$prefix, $data['type'], $data['name']));
+    }
+}
diff --git a/tests/Test/BlackBoxPushGatewayTest.php b/tests/Test/BlackBoxPushGatewayTest.php
index 26490c6..8fb793c 100644
--- a/tests/Test/BlackBoxPushGatewayTest.php
+++ b/tests/Test/BlackBoxPushGatewayTest.php
@@ -33,7 +33,7 @@ public function pushGatewayShouldWork()
             $metrics
         );
 
-        $pushGateway->delete('my_job', array('instance' => 'foo'));
+        $pushGateway->delete($registry,'my_job', array('instance' => 'foo'));
 
         $httpClient = new Client();
         $metrics = $httpClient->get("http://pushgateway:9091/metrics")->getBody()->getContents();
diff --git a/tests/Test/Prometheus/Predis/CollectorRegistryTest.php b/tests/Test/Prometheus/Predis/CollectorRegistryTest.php
new file mode 100644
index 0000000..1c1c038
--- /dev/null
+++ b/tests/Test/Prometheus/Predis/CollectorRegistryTest.php
@@ -0,0 +1,16 @@
+<?php
+
+
+namespace Test\Prometheus\Predis;
+
+use Prometheus\Storage\Predis;
+use Test\Prometheus\AbstractCollectorRegistryTest;
+
+class CollectorRegistryTest extends AbstractCollectorRegistryTest
+{
+    public function configureAdapter()
+    {
+        $this->adapter = new Predis(array('host' => REDIS_HOST));
+        $this->adapter->flushRedis();
+    }
+}
diff --git a/tests/Test/Prometheus/Predis/CounterTest.php b/tests/Test/Prometheus/Predis/CounterTest.php
new file mode 100644
index 0000000..eed8bbd
--- /dev/null
+++ b/tests/Test/Prometheus/Predis/CounterTest.php
@@ -0,0 +1,20 @@
+<?php
+
+
+namespace Test\Prometheus\Predis;
+
+use Prometheus\Storage\Predis;
+use Test\Prometheus\AbstractCounterTest;
+
+/**
+ * See https://prometheus.io/docs/instrumenting/exposition_formats/
+ */
+class CounterTest extends AbstractCounterTest
+{
+
+    public function configureAdapter()
+    {
+        $this->adapter = new Predis(array('host' => REDIS_HOST));
+        $this->adapter->flushRedis();
+    }
+}
diff --git a/tests/Test/Prometheus/Predis/GaugeTest.php b/tests/Test/Prometheus/Predis/GaugeTest.php
new file mode 100644
index 0000000..064676b
--- /dev/null
+++ b/tests/Test/Prometheus/Predis/GaugeTest.php
@@ -0,0 +1,20 @@
+<?php
+
+
+namespace Test\Prometheus\Predis;
+
+use Prometheus\Storage\Predis;
+use Test\Prometheus\AbstractGaugeTest;
+
+/**
+ * See https://prometheus.io/docs/instrumenting/exposition_formats/
+ */
+class GaugeTest extends AbstractGaugeTest
+{
+
+    public function configureAdapter()
+    {
+        $this->adapter = new Predis(array('host' => REDIS_HOST));
+        $this->adapter->flushRedis();
+    }
+}
diff --git a/tests/Test/Prometheus/Predis/HistogramTest.php b/tests/Test/Prometheus/Predis/HistogramTest.php
new file mode 100644
index 0000000..474c203
--- /dev/null
+++ b/tests/Test/Prometheus/Predis/HistogramTest.php
@@ -0,0 +1,20 @@
+<?php
+
+
+namespace Test\Prometheus\Predis;
+
+use Prometheus\Storage\Predis;
+use Test\Prometheus\AbstractHistogramTest;
+
+/**
+ * See https://prometheus.io/docs/instrumenting/exposition_formats/
+ */
+class HistogramTest extends AbstractHistogramTest
+{
+
+    public function configureAdapter()
+    {
+        $this->adapter = new Predis(array('host' => REDIS_HOST));
+        $this->adapter->flushRedis();
+    }
+}

From 5f5113a3b0e6332fd5f56b7ad712b62b5c87e3be Mon Sep 17 00:00:00 2001
From: Sergey Protko <fesors@gmail.com>
Date: Wed, 27 Sep 2017 17:01:50 +0300
Subject: [PATCH 2/3] Remove handling of connection from predis adapter

---
 examples/flush_adapter.php                    |  6 +-
 examples/metrics.php                          |  6 +-
 examples/pushgateway.php                      |  6 +-
 examples/some_counter.php                     |  6 +-
 examples/some_gauge.php                       |  6 +-
 examples/some_histogram.php                   |  6 +-
 src/Prometheus/Storage/Predis.php             | 70 +++----------------
 .../Predis/CollectorRegistryTest.php          |  2 +-
 tests/Test/Prometheus/Predis/CounterTest.php  |  2 +-
 tests/Test/Prometheus/Predis/GaugeTest.php    |  2 +-
 .../Test/Prometheus/Predis/HistogramTest.php  |  2 +-
 11 files changed, 33 insertions(+), 81 deletions(-)

diff --git a/examples/flush_adapter.php b/examples/flush_adapter.php
index a2f98c0..9433765 100644
--- a/examples/flush_adapter.php
+++ b/examples/flush_adapter.php
@@ -9,9 +9,9 @@
     $redisAdapter = new Prometheus\Storage\Redis(array('host' => REDIS_HOST));
     $redisAdapter->flushRedis();
 } elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis([
-        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
-    ]);
+    $adapter = new Prometheus\Storage\Predis(
+        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
+    );
     $adapter->flushRedis();
 } elseif ($adapter === 'apc') {
     $apcAdapter = new Prometheus\Storage\APC();
diff --git a/examples/metrics.php b/examples/metrics.php
index 76c834a..f816bd8 100644
--- a/examples/metrics.php
+++ b/examples/metrics.php
@@ -12,9 +12,9 @@
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
 } elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis([
-        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
-    ]);
+    $adapter = new Prometheus\Storage\Predis(
+        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
+    );
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/examples/pushgateway.php b/examples/pushgateway.php
index 6c4d789..51438f6 100644
--- a/examples/pushgateway.php
+++ b/examples/pushgateway.php
@@ -10,9 +10,9 @@
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
 } elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis([
-        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
-    ]);
+    $adapter = new Prometheus\Storage\Predis(
+        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
+    );
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/examples/some_counter.php b/examples/some_counter.php
index 58fc6ff..0c52cd1 100644
--- a/examples/some_counter.php
+++ b/examples/some_counter.php
@@ -11,9 +11,9 @@
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
 } elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis([
-        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
-    ]);
+    $adapter = new Prometheus\Storage\Predis(
+        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
+    );
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/examples/some_gauge.php b/examples/some_gauge.php
index b847131..7573761 100644
--- a/examples/some_gauge.php
+++ b/examples/some_gauge.php
@@ -14,9 +14,9 @@
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
 } elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis([
-        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
-    ]);
+    $adapter = new Prometheus\Storage\Predis(
+        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
+    );
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/examples/some_histogram.php b/examples/some_histogram.php
index a618cbe..9a75a46 100644
--- a/examples/some_histogram.php
+++ b/examples/some_histogram.php
@@ -13,9 +13,9 @@
     Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
     $adapter = new Prometheus\Storage\Redis();
 } elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis([
-        'host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'
-    ]);
+    $adapter = new Prometheus\Storage\Predis(
+        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
+    );
 } elseif ($adapter === 'apc') {
     $adapter = new Prometheus\Storage\APC();
 } elseif ($adapter === 'in-memory') {
diff --git a/src/Prometheus/Storage/Predis.php b/src/Prometheus/Storage/Predis.php
index d4a3258..bff5208 100644
--- a/src/Prometheus/Storage/Predis.php
+++ b/src/Prometheus/Storage/Predis.php
@@ -13,33 +13,16 @@ class Predis implements Adapter
 {
     const PROMETHEUS_METRIC_KEYS_SUFFIX = '_METRIC_KEYS';
 
-    private static $defaultOptions = [
-        'host' => '127.0.0.1',
-        'port' => 6379,
-        'timeout' => 0.1,
-        'read_timeout' => 10,
-        'persistent_connections' => false,
-    ];
-
     private static $prefix = 'PROMETHEUS_';
 
-    private $options;
     /**
      * @var Client
      */
     private $predis;
 
-    public function __construct(array $options = array())
+    public function __construct(Client $predis)
     {
-        $this->options = array_merge(self::$defaultOptions, $options);
-    }
-
-    /**
-     * @param array $options
-     */
-    public static function setDefaultOptions(array $options)
-    {
-        self::$defaultOptions = array_merge(self::$defaultOptions, $options);
+        $this->predis = $predis;
     }
 
     public static function setPrefix($prefix)
@@ -49,7 +32,6 @@ public static function setPrefix($prefix)
 
     public function flushRedis()
     {
-        $this->openConnection();
         $this->predis->flushall();
     }
 
@@ -59,7 +41,6 @@ public function flushRedis()
      */
     public function collect()
     {
-        $this->openConnection();
         $metrics = $this->collectHistograms();
         $metrics = array_merge($metrics, $this->collectGauges());
         $metrics = array_merge($metrics, $this->collectCounters());
@@ -71,30 +52,8 @@ function (array $metric) {
         );
     }
 
-    /**
-     * @throws StorageException
-     */
-    private function openConnection()
-    {
-        try {
-
-            $this->predis = new Client([
-                'scheme' => 'tcp',
-                'host'   => $this->options['host'],
-                'port'   => $this->options['port'],
-                'timeout' => $this->options['timeout'],
-                'read_write_timeout' => $this->options['read_timeout'],
-                'persistent' => $this->options['persistent_connections'],
-            ]);
-
-        } catch (\RedisException $e) {
-            throw new StorageException("Can't connect to Redis server", 0, $e);
-        }
-    }
-
     public function updateHistogram(array $data)
     {
-        $this->openConnection();
         $bucketToIncrease = '+Inf';
         foreach ($data['buckets'] as $bucket) {
             if ($data['value'] <= $bucket) {
@@ -105,6 +64,7 @@ public function updateHistogram(array $data)
         $metaData = $data;
         unset($metaData['value']);
         unset($metaData['labelValues']);
+
         $this->predis->eval(<<<LUA
 local increment = redis.call('hIncrByFloat', KEYS[1], KEYS[2], ARGV[1])
 redis.call('hIncrBy', KEYS[1], KEYS[3], 1)
@@ -126,7 +86,6 @@ public function updateHistogram(array $data)
 
     public function updateGauge(array $data)
     {
-        $this->openConnection();
         $metaData = $data;
         unset($metaData['value']);
         unset($metaData['labelValues']);
@@ -159,7 +118,6 @@ public function updateGauge(array $data)
 
     public function updateCounter(array $data)
     {
-        $this->openConnection();
         $metaData = $data;
         unset($metaData['value']);
         unset($metaData['labelValues']);
@@ -219,22 +177,16 @@ private function collectHistograms()
                 $acc = 0;
                 foreach ($histogram['buckets'] as $bucket) {
                     $bucketKey = json_encode(array('b' => $bucket, 'labelValues' => $labelValues));
-                    if (!isset($raw[$bucketKey])) {
-                        $histogram['samples'][] = array(
-                            'name' => $histogram['name'] . '_bucket',
-                            'labelNames' => array('le'),
-                            'labelValues' => array_merge($labelValues, array($bucket)),
-                            'value' => $acc
-                        );
-                    } else {
+                    if (isset($raw[$bucketKey])) {
                         $acc += $raw[$bucketKey];
-                        $histogram['samples'][] = array(
-                            'name' => $histogram['name'] . '_bucket',
-                            'labelNames' => array('le'),
-                            'labelValues' => array_merge($labelValues, array($bucket)),
-                            'value' => $acc
-                        );
                     }
+
+                    $histogram['samples'][] = array(
+                        'name' => $histogram['name'] . '_bucket',
+                        'labelNames' => array('le'),
+                        'labelValues' => array_merge($labelValues, array($bucket)),
+                        'value' => $acc
+                    );
                 }
 
                 // Add the count
diff --git a/tests/Test/Prometheus/Predis/CollectorRegistryTest.php b/tests/Test/Prometheus/Predis/CollectorRegistryTest.php
index 1c1c038..9bb836b 100644
--- a/tests/Test/Prometheus/Predis/CollectorRegistryTest.php
+++ b/tests/Test/Prometheus/Predis/CollectorRegistryTest.php
@@ -10,7 +10,7 @@ class CollectorRegistryTest extends AbstractCollectorRegistryTest
 {
     public function configureAdapter()
     {
-        $this->adapter = new Predis(array('host' => REDIS_HOST));
+        $this->adapter = new Predis(new \Predis\Client(['host' => REDIS_HOST]));
         $this->adapter->flushRedis();
     }
 }
diff --git a/tests/Test/Prometheus/Predis/CounterTest.php b/tests/Test/Prometheus/Predis/CounterTest.php
index eed8bbd..7568ff6 100644
--- a/tests/Test/Prometheus/Predis/CounterTest.php
+++ b/tests/Test/Prometheus/Predis/CounterTest.php
@@ -14,7 +14,7 @@ class CounterTest extends AbstractCounterTest
 
     public function configureAdapter()
     {
-        $this->adapter = new Predis(array('host' => REDIS_HOST));
+        $this->adapter = new Predis(new \Predis\Client(['host' => REDIS_HOST]));
         $this->adapter->flushRedis();
     }
 }
diff --git a/tests/Test/Prometheus/Predis/GaugeTest.php b/tests/Test/Prometheus/Predis/GaugeTest.php
index 064676b..fe14939 100644
--- a/tests/Test/Prometheus/Predis/GaugeTest.php
+++ b/tests/Test/Prometheus/Predis/GaugeTest.php
@@ -14,7 +14,7 @@ class GaugeTest extends AbstractGaugeTest
 
     public function configureAdapter()
     {
-        $this->adapter = new Predis(array('host' => REDIS_HOST));
+        $this->adapter = new Predis(new \Predis\Client(['host' => REDIS_HOST]));
         $this->adapter->flushRedis();
     }
 }
diff --git a/tests/Test/Prometheus/Predis/HistogramTest.php b/tests/Test/Prometheus/Predis/HistogramTest.php
index 474c203..caa7397 100644
--- a/tests/Test/Prometheus/Predis/HistogramTest.php
+++ b/tests/Test/Prometheus/Predis/HistogramTest.php
@@ -14,7 +14,7 @@ class HistogramTest extends AbstractHistogramTest
 
     public function configureAdapter()
     {
-        $this->adapter = new Predis(array('host' => REDIS_HOST));
+        $this->adapter = new Predis(new \Predis\Client(['host' => REDIS_HOST]));
         $this->adapter->flushRedis();
     }
 }

From e2d1074c978fbcbf759b0372631397250153576f Mon Sep 17 00:00:00 2001
From: Sergey Protko <fesors@gmail.com>
Date: Mon, 26 Feb 2018 23:31:27 +0300
Subject: [PATCH 3/3] Introduce redis client adapter

 - Encapsulate differences between predis and redis behind
single abstraction.
 - Reduce duplication in tests
---
 examples/flush_adapter.php                    |  22 +-
 examples/initialize.php                       |  21 ++
 examples/metrics.php                          |  14 +-
 examples/pushgateway.php                      |  15 +-
 examples/some_counter.php                     |  15 +-
 examples/some_gauge.php                       |  15 +-
 examples/some_histogram.php                   |  15 +-
 src/Prometheus/Storage/Predis.php             | 287 ------------------
 src/Prometheus/Storage/Redis.php              |  98 ++----
 src/Prometheus/Storage/RedisAdapter.php       | 119 ++++++++
 .../Predis/CollectorRegistryTest.php          |   8 +-
 tests/Test/Prometheus/Predis/CounterTest.php  |   9 +-
 tests/Test/Prometheus/Predis/GaugeTest.php    |   9 +-
 .../Test/Prometheus/Predis/HistogramTest.php  |   9 +-
 .../Prometheus/Predis/InitializationTrait.php |  17 ++
 .../Redis/CollectorRegistryTest.php           |   8 +-
 tests/Test/Prometheus/Redis/CounterTest.php   |   9 +-
 tests/Test/Prometheus/Redis/GaugeTest.php     |   9 +-
 tests/Test/Prometheus/Redis/HistogramTest.php |   9 +-
 .../Prometheus/Redis/InitializationTrait.php  |  17 ++
 .../{RedisTest.php => RedisAdapterTest.php}   |   6 +-
 21 files changed, 226 insertions(+), 505 deletions(-)
 create mode 100644 examples/initialize.php
 delete mode 100644 src/Prometheus/Storage/Predis.php
 create mode 100644 src/Prometheus/Storage/RedisAdapter.php
 create mode 100644 tests/Test/Prometheus/Predis/InitializationTrait.php
 create mode 100644 tests/Test/Prometheus/Redis/InitializationTrait.php
 rename tests/Test/Prometheus/Storage/{RedisTest.php => RedisAdapterTest.php} (61%)

diff --git a/examples/flush_adapter.php b/examples/flush_adapter.php
index 9433765..4c7eecf 100644
--- a/examples/flush_adapter.php
+++ b/examples/flush_adapter.php
@@ -1,22 +1,12 @@
 <?php
 require __DIR__ . '/../vendor/autoload.php';
 
-$adapter = $_GET['adapter'];
+$adapter = require __DIR__ . '/initialize.php';
 
-if ($adapter === 'redis') {
-    define('REDIS_HOST', isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1');
-
-    $redisAdapter = new Prometheus\Storage\Redis(array('host' => REDIS_HOST));
-    $redisAdapter->flushRedis();
-} elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis(
-        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
-    );
+if ($adapter instanceof \Prometheus\Storage\Redis) {
     $adapter->flushRedis();
-} elseif ($adapter === 'apc') {
-    $apcAdapter = new Prometheus\Storage\APC();
-    $apcAdapter->flushAPC();
-} elseif ($adapter === 'in-memory') {
-    $inMemoryAdapter = new Prometheus\Storage\InMemory();
-    $inMemoryAdapter->flushMemory();
+} elseif ($adapter instanceof \Prometheus\Storage\APC) {
+    $adapter->flushAPC();
+} elseif ($adapter instanceof \Prometheus\Storage\InMemory) {
+    $adapter->flushMemory();
 }
\ No newline at end of file
diff --git a/examples/initialize.php b/examples/initialize.php
new file mode 100644
index 0000000..406119d
--- /dev/null
+++ b/examples/initialize.php
@@ -0,0 +1,21 @@
+<?php
+
+$adapterName = $_GET['adapter'];
+
+switch($adapterName) {
+    case "redis":
+        return \Prometheus\Storage\Redis::usingRedis(
+            new \Redis(),
+            array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1')
+        );
+    case "predis":
+        return  Prometheus\Storage\Redis::usingPredis(
+            new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
+        );
+    case "apc":
+        return new Prometheus\Storage\APC();
+    case "in-memory":
+        return new Prometheus\Storage\InMemory();
+    default:
+        throw new \RuntimeException(sprintf('Adapter "" is not supported', $adapterName));
+}
diff --git a/examples/metrics.php b/examples/metrics.php
index f816bd8..6742112 100644
--- a/examples/metrics.php
+++ b/examples/metrics.php
@@ -6,20 +6,8 @@
 use Prometheus\RenderTextFormat;
 use Prometheus\Storage\Redis;
 
-$adapter = $_GET['adapter'];
+$adapter = require __DIR__ . '/initialize.php';
 
-if ($adapter === 'redis') {
-    Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
-    $adapter = new Prometheus\Storage\Redis();
-} elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis(
-        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
-    );
-} elseif ($adapter === 'apc') {
-    $adapter = new Prometheus\Storage\APC();
-} elseif ($adapter === 'in-memory') {
-    $adapter = new Prometheus\Storage\InMemory();
-}
 $registry = new CollectorRegistry($adapter);
 $renderer = new RenderTextFormat();
 $result = $renderer->render($registry->getMetricFamilySamples());
diff --git a/examples/pushgateway.php b/examples/pushgateway.php
index 51438f6..b69e9af 100644
--- a/examples/pushgateway.php
+++ b/examples/pushgateway.php
@@ -4,20 +4,7 @@
 use Prometheus\Storage\Redis;
 use Prometheus\CollectorRegistry;
 
-$adapter = $_GET['adapter'];
-
-if ($adapter === 'redis') {
-    Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
-    $adapter = new Prometheus\Storage\Redis();
-} elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis(
-        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
-    );
-} elseif ($adapter === 'apc') {
-    $adapter = new Prometheus\Storage\APC();
-} elseif ($adapter === 'in-memory') {
-    $adapter = new Prometheus\Storage\InMemory();
-}
+$adapter = require __DIR__ . '/initialize.php';
 
 $registry = new CollectorRegistry($adapter);
 
diff --git a/examples/some_counter.php b/examples/some_counter.php
index 0c52cd1..3851e7c 100644
--- a/examples/some_counter.php
+++ b/examples/some_counter.php
@@ -5,20 +5,7 @@
 use Prometheus\CollectorRegistry;
 use Prometheus\Storage\Redis;
 
-$adapter = $_GET['adapter'];
-
-if ($adapter === 'redis') {
-    Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
-    $adapter = new Prometheus\Storage\Redis();
-} elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis(
-        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
-    );
-} elseif ($adapter === 'apc') {
-    $adapter = new Prometheus\Storage\APC();
-} elseif ($adapter === 'in-memory') {
-    $adapter = new Prometheus\Storage\InMemory();
-}
+$adapter = require __DIR__ . '/initialize.php';
 $registry = new CollectorRegistry($adapter);
 
 $counter = $registry->registerCounter('test', 'some_counter', 'it increases', ['type']);
diff --git a/examples/some_gauge.php b/examples/some_gauge.php
index 7573761..a128cb2 100644
--- a/examples/some_gauge.php
+++ b/examples/some_gauge.php
@@ -8,20 +8,7 @@
 
 error_log('c='. $_GET['c']);
 
-$adapter = $_GET['adapter'];
-
-if ($adapter === 'redis') {
-    Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
-    $adapter = new Prometheus\Storage\Redis();
-} elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis(
-        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
-    );
-} elseif ($adapter === 'apc') {
-    $adapter = new Prometheus\Storage\APC();
-} elseif ($adapter === 'in-memory') {
-    $adapter = new Prometheus\Storage\InMemory();
-}
+$adapter = require __DIR__ . '/initialize.php';
 $registry = new CollectorRegistry($adapter);
 
 $gauge = $registry->registerGauge('test', 'some_gauge', 'it sets', ['type']);
diff --git a/examples/some_histogram.php b/examples/some_histogram.php
index 9a75a46..0157c7c 100644
--- a/examples/some_histogram.php
+++ b/examples/some_histogram.php
@@ -7,20 +7,7 @@
 
 error_log('c='. $_GET['c']);
 
-$adapter = $_GET['adapter'];
-
-if ($adapter === 'redis') {
-    Redis::setDefaultOptions(array('host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'));
-    $adapter = new Prometheus\Storage\Redis();
-} elseif ($adapter === 'predis') {
-    $adapter = new Prometheus\Storage\Predis(
-        new \Predis\Client(['host' => isset($_SERVER['REDIS_HOST']) ? $_SERVER['REDIS_HOST'] : '127.0.0.1'])
-    );
-} elseif ($adapter === 'apc') {
-    $adapter = new Prometheus\Storage\APC();
-} elseif ($adapter === 'in-memory') {
-    $adapter = new Prometheus\Storage\InMemory();
-}
+$adapter = require __DIR__ . '/initialize.php';
 $registry = new CollectorRegistry($adapter);
 
 $histogram = $registry->registerHistogram('test', 'some_histogram', 'it observes', ['type'], [0.1, 1, 2, 3.5, 4, 5, 6, 7, 8, 9]);
diff --git a/src/Prometheus/Storage/Predis.php b/src/Prometheus/Storage/Predis.php
deleted file mode 100644
index bff5208..0000000
--- a/src/Prometheus/Storage/Predis.php
+++ /dev/null
@@ -1,287 +0,0 @@
-<?php
-
-namespace Prometheus\Storage;
-
-use Predis\Client;
-use Prometheus\Counter;
-use Prometheus\Exception\StorageException;
-use Prometheus\Gauge;
-use Prometheus\Histogram;
-use Prometheus\MetricFamilySamples;
-
-class Predis implements Adapter
-{
-    const PROMETHEUS_METRIC_KEYS_SUFFIX = '_METRIC_KEYS';
-
-    private static $prefix = 'PROMETHEUS_';
-
-    /**
-     * @var Client
-     */
-    private $predis;
-
-    public function __construct(Client $predis)
-    {
-        $this->predis = $predis;
-    }
-
-    public static function setPrefix($prefix)
-    {
-        self::$prefix = $prefix;
-    }
-
-    public function flushRedis()
-    {
-        $this->predis->flushall();
-    }
-
-    /**
-     * @return MetricFamilySamples[]
-     * @throws StorageException
-     */
-    public function collect()
-    {
-        $metrics = $this->collectHistograms();
-        $metrics = array_merge($metrics, $this->collectGauges());
-        $metrics = array_merge($metrics, $this->collectCounters());
-        return array_map(
-            function (array $metric) {
-                return new MetricFamilySamples($metric);
-            },
-            $metrics
-        );
-    }
-
-    public function updateHistogram(array $data)
-    {
-        $bucketToIncrease = '+Inf';
-        foreach ($data['buckets'] as $bucket) {
-            if ($data['value'] <= $bucket) {
-                $bucketToIncrease = $bucket;
-                break;
-            }
-        }
-        $metaData = $data;
-        unset($metaData['value']);
-        unset($metaData['labelValues']);
-
-        $this->predis->eval(<<<LUA
-local increment = redis.call('hIncrByFloat', KEYS[1], KEYS[2], ARGV[1])
-redis.call('hIncrBy', KEYS[1], KEYS[3], 1)
-if increment == ARGV[1] then
-    redis.call('hSet', KEYS[1], '__meta', ARGV[2])
-    redis.call('sAdd', KEYS[4], KEYS[1])
-end
-LUA
-            ,
-            4,
-            $this->toMetricKey($data),
-            json_encode(array('b' => 'sum', 'labelValues' => $data['labelValues'])),
-            json_encode(array('b' => $bucketToIncrease, 'labelValues' => $data['labelValues'])),
-            self::$prefix . Histogram::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
-            $data['value'],
-            json_encode($metaData)
-        );
-    }
-
-    public function updateGauge(array $data)
-    {
-        $metaData = $data;
-        unset($metaData['value']);
-        unset($metaData['labelValues']);
-        unset($metaData['command']);
-        $this->predis->eval(<<<LUA
-local result = redis.call(KEYS[2], KEYS[1], KEYS[4], ARGV[1])
-
-if KEYS[2] == 'hSet' then
-    if result == 1 then
-        redis.call('hSet', KEYS[1], '__meta', ARGV[2])
-        redis.call('sAdd', KEYS[3], KEYS[1])
-    end
-else
-    if result == ARGV[1] then
-        redis.call('hSet', KEYS[1], '__meta', ARGV[2])
-        redis.call('sAdd', KEYS[3], KEYS[1])
-    end
-end
-LUA
-            ,
-            4,
-            $this->toMetricKey($data),
-            $this->getRedisCommand($data['command']),
-            self::$prefix . Gauge::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
-            json_encode($data['labelValues']),
-            $data['value'],
-            json_encode($metaData)
-        );
-    }
-
-    public function updateCounter(array $data)
-    {
-        $metaData = $data;
-        unset($metaData['value']);
-        unset($metaData['labelValues']);
-        unset($metaData['command']);
-        $result = $this->predis->eval(<<<LUA
-local result = redis.call(KEYS[2], KEYS[1], KEYS[4], ARGV[1])
-if result == tonumber(ARGV[1]) then
-    redis.call('hMSet', KEYS[1], '__meta', ARGV[2])
-    redis.call('sAdd', KEYS[3], KEYS[1])
-end
-return result
-LUA
-            ,
-            4,
-            $this->toMetricKey($data),
-            $this->getRedisCommand($data['command']),
-            self::$prefix . Counter::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
-            json_encode($data['labelValues']),
-            $data['value'],
-            json_encode($metaData)
-        );
-        return $result;
-    }
-
-    private function collectHistograms()
-    {
-        $keys = $this->predis->smembers(self::$prefix . Histogram::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
-        sort($keys);
-        $histograms = array();
-        foreach ($keys as $key) {
-            $raw = $this->predis->hgetall($key);
-            $histogram = json_decode($raw['__meta'], true);
-            unset($raw['__meta']);
-            $histogram['samples'] = array();
-
-            // Add the Inf bucket so we can compute it later on
-            $histogram['buckets'][] = '+Inf';
-
-            $allLabelValues = array();
-            foreach (array_keys($raw) as $k) {
-                $d = json_decode($k, true);
-                if ($d['b'] == 'sum') {
-                    continue;
-                }
-                $allLabelValues[] = $d['labelValues'];
-            }
-
-            // We need set semantics.
-            // This is the equivalent of array_unique but for arrays of arrays.
-            $allLabelValues = array_map("unserialize", array_unique(array_map("serialize", $allLabelValues)));
-            sort($allLabelValues);
-
-            foreach ($allLabelValues as $labelValues) {
-                // Fill up all buckets.
-                // If the bucket doesn't exist fill in values from
-                // the previous one.
-                $acc = 0;
-                foreach ($histogram['buckets'] as $bucket) {
-                    $bucketKey = json_encode(array('b' => $bucket, 'labelValues' => $labelValues));
-                    if (isset($raw[$bucketKey])) {
-                        $acc += $raw[$bucketKey];
-                    }
-
-                    $histogram['samples'][] = array(
-                        'name' => $histogram['name'] . '_bucket',
-                        'labelNames' => array('le'),
-                        'labelValues' => array_merge($labelValues, array($bucket)),
-                        'value' => $acc
-                    );
-                }
-
-                // Add the count
-                $histogram['samples'][] = array(
-                    'name' => $histogram['name'] . '_count',
-                    'labelNames' => array(),
-                    'labelValues' => $labelValues,
-                    'value' => $acc
-                );
-
-                // Add the sum
-                $histogram['samples'][] = array(
-                    'name' => $histogram['name'] . '_sum',
-                    'labelNames' => array(),
-                    'labelValues' => $labelValues,
-                    'value' => $raw[json_encode(array('b' => 'sum', 'labelValues' => $labelValues))]
-                );
-            }
-            $histograms[] = $histogram;
-        }
-        return $histograms;
-    }
-
-    private function collectGauges()
-    {
-        $keys = $this->predis->smembers(self::$prefix . Gauge::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
-        sort($keys);
-        $gauges = array();
-        foreach ($keys as $key) {
-            $raw = $this->predis->hgetall($key);
-            $gauge = json_decode($raw['__meta'], true);
-            unset($raw['__meta']);
-            $gauge['samples'] = array();
-            foreach ($raw as $k => $value) {
-                $gauge['samples'][] = array(
-                    'name' => $gauge['name'],
-                    'labelNames' => array(),
-                    'labelValues' => json_decode($k, true),
-                    'value' => $value
-                );
-            }
-            usort($gauge['samples'], function($a, $b){
-                return strcmp(implode("", $a['labelValues']), implode("", $b['labelValues']));
-            });
-            $gauges[] = $gauge;
-        }
-        return $gauges;
-    }
-
-    private function collectCounters()
-    {
-        $keys = $this->predis->smembers(self::$prefix . Counter::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
-        sort($keys);
-        $counters = array();
-        foreach ($keys as $key) {
-            $raw = $this->predis->hgetall($key);
-            $counter = json_decode($raw['__meta'], true);
-            unset($raw['__meta']);
-            $counter['samples'] = array();
-            foreach ($raw as $k => $value) {
-                $counter['samples'][] = array(
-                    'name' => $counter['name'],
-                    'labelNames' => array(),
-                    'labelValues' => json_decode($k, true),
-                    'value' => $value
-                );
-            }
-            usort($counter['samples'], function($a, $b){
-                return strcmp(implode("", $a['labelValues']), implode("", $b['labelValues']));
-            });
-            $counters[] = $counter;
-        }
-        return $counters;
-    }
-
-    private function getRedisCommand($cmd)
-    {
-        switch ($cmd) {
-            case Adapter::COMMAND_INCREMENT_INTEGER:
-                return 'hIncrBy';
-            case Adapter::COMMAND_INCREMENT_FLOAT:
-                return 'hIncrByFloat';
-            case Adapter::COMMAND_SET:
-                return 'hSet';
-            default:
-                throw new \InvalidArgumentException("Unknown command");
-        }
-    }
-
-    /**
-     * @param array $data
-     * @return string
-     */
-    private function toMetricKey(array $data)
-    {
-        return implode(':', array(self::$prefix, $data['type'], $data['name']));
-    }
-}
diff --git a/src/Prometheus/Storage/Redis.php b/src/Prometheus/Storage/Redis.php
index f38391b..d433266 100644
--- a/src/Prometheus/Storage/Redis.php
+++ b/src/Prometheus/Storage/Redis.php
@@ -3,6 +3,7 @@
 namespace Prometheus\Storage;
 
 
+use Predis\Client;
 use Prometheus\Counter;
 use Prometheus\Exception\StorageException;
 use Prometheus\Gauge;
@@ -13,55 +14,40 @@ class Redis implements Adapter
 {
     const PROMETHEUS_METRIC_KEYS_SUFFIX = '_METRIC_KEYS';
 
-    private static $defaultOptions = array();
-    private static $prefix = 'PROMETHEUS_';
+    private $prefix = 'PROMETHEUS_';
 
-    private $options;
     private $redis;
 
-    public function __construct(array $options = array())
+    /**
+     * Redis constructor.
+     * @param RedisAdapter $redis
+     * @param string $prefix
+     */
+    public function __construct(RedisAdapter $redis, $prefix = 'PROMETHEUS_')
     {
-        // with php 5.3 we cannot initialize the options directly on the field definition
-        // so we initialize them here for now
-        if (!isset(self::$defaultOptions['host'])) {
-            self::$defaultOptions['host'] = '127.0.0.1';
-        }
-        if (!isset(self::$defaultOptions['port'])) {
-            self::$defaultOptions['port'] = 6379;
-        }
-        if (!isset(self::$defaultOptions['timeout'])) {
-            self::$defaultOptions['timeout'] = 0.1; // in seconds
-        }
-        if (!isset(self::$defaultOptions['read_timeout'])) {
-            self::$defaultOptions['read_timeout'] = 10; // in seconds
-        }
-        if (!isset(self::$defaultOptions['persistent_connections'])) {
-            self::$defaultOptions['persistent_connections'] = false;
-        }
-        if (!isset(self::$defaultOptions['password'])) {
-            self::$defaultOptions['password'] = null;
-        }
-
-        $this->options = array_merge(self::$defaultOptions, $options);
-        $this->redis = new \Redis();
+        $this->redis = $redis;
     }
 
     /**
-     * @param array $options
+     * @param string $prefix
      */
-    public static function setDefaultOptions(array $options)
+    public function setPrefix($prefix)
+    {
+        $this->prefix = $prefix;
+    }
+
+    public static function usingRedis(\Redis $redis, array $options)
     {
-        self::$defaultOptions = array_merge(self::$defaultOptions, $options);
+        return new self(RedisAdapter::forRedis($redis, $options));
     }
 
-    public static function setPrefix($prefix)
+    public static function usingPredis(Client $redis)
     {
-        self::$prefix = $prefix;
+        return new self(RedisAdapter::forPredis($redis));
     }
 
     public function flushRedis()
     {
-        $this->openConnection();
         $this->redis->flushAll();
     }
 
@@ -71,7 +57,6 @@ public function flushRedis()
      */
     public function collect()
     {
-        $this->openConnection();
         $metrics = $this->collectHistograms();
         $metrics = array_merge($metrics, $this->collectGauges());
         $metrics = array_merge($metrics, $this->collectCounters());
@@ -83,29 +68,8 @@ function (array $metric) {
         );
     }
 
-    /**
-     * @throws StorageException
-     */
-    private function openConnection()
-    {
-        try {
-            if ($this->options['persistent_connections']) {
-                @$this->redis->pconnect($this->options['host'], $this->options['port'], $this->options['timeout']);
-            } else {
-                @$this->redis->connect($this->options['host'], $this->options['port'], $this->options['timeout']);
-            }
-            if ($this->options['password']) {
-                $this->redis->auth($this->options['password']);
-            }
-            $this->redis->setOption(\Redis::OPT_READ_TIMEOUT, $this->options['read_timeout']);
-        } catch (\RedisException $e) {
-            throw new StorageException("Can't connect to Redis server", 0, $e);
-        }
-    }
-
     public function updateHistogram(array $data)
     {
-        $this->openConnection();
         $bucketToIncrease = '+Inf';
         foreach ($data['buckets'] as $bucket) {
             if ($data['value'] <= $bucket) {
@@ -116,7 +80,7 @@ public function updateHistogram(array $data)
         $metaData = $data;
         unset($metaData['value']);
         unset($metaData['labelValues']);
-        $this->redis->eval(<<<LUA
+        $this->redis->evaluate(<<<LUA
 local increment = redis.call('hIncrByFloat', KEYS[1], KEYS[2], ARGV[1])
 redis.call('hIncrBy', KEYS[1], KEYS[3], 1)
 if increment == ARGV[1] then
@@ -129,7 +93,7 @@ public function updateHistogram(array $data)
                 $this->toMetricKey($data),
                 json_encode(array('b' => 'sum', 'labelValues' => $data['labelValues'])),
                 json_encode(array('b' => $bucketToIncrease, 'labelValues' => $data['labelValues'])),
-                self::$prefix . Histogram::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
+                $this->prefix . Histogram::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
                 $data['value'],
                 json_encode($metaData),
             ),
@@ -139,12 +103,12 @@ public function updateHistogram(array $data)
 
     public function updateGauge(array $data)
     {
-        $this->openConnection();
+
         $metaData = $data;
         unset($metaData['value']);
         unset($metaData['labelValues']);
         unset($metaData['command']);
-        $this->redis->eval(<<<LUA
+        $this->redis->evaluate(<<<LUA
 local result = redis.call(KEYS[2], KEYS[1], KEYS[4], ARGV[1])
 
 if KEYS[2] == 'hSet' then
@@ -163,7 +127,7 @@ public function updateGauge(array $data)
             array(
                 $this->toMetricKey($data),
                 $this->getRedisCommand($data['command']),
-                self::$prefix . Gauge::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
+                $this->prefix . Gauge::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
                 json_encode($data['labelValues']),
                 $data['value'],
                 json_encode($metaData),
@@ -174,12 +138,11 @@ public function updateGauge(array $data)
 
     public function updateCounter(array $data)
     {
-        $this->openConnection();
         $metaData = $data;
         unset($metaData['value']);
         unset($metaData['labelValues']);
         unset($metaData['command']);
-        $result = $this->redis->eval(<<<LUA
+        $result = $this->redis->evaluate(<<<LUA
 local result = redis.call(KEYS[2], KEYS[1], KEYS[4], ARGV[1])
 if result == tonumber(ARGV[1]) then
     redis.call('hMSet', KEYS[1], '__meta', ARGV[2])
@@ -191,7 +154,7 @@ public function updateCounter(array $data)
             array(
                 $this->toMetricKey($data),
                 $this->getRedisCommand($data['command']),
-                self::$prefix . Counter::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
+                $this->prefix . Counter::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX,
                 json_encode($data['labelValues']),
                 $data['value'],
                 json_encode($metaData),
@@ -203,7 +166,7 @@ public function updateCounter(array $data)
 
     private function collectHistograms()
     {
-        $keys = $this->redis->sMembers(self::$prefix . Histogram::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
+        $keys = $this->redis->sMembers($this->prefix . Histogram::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
         sort($keys);
         $histograms = array();
         foreach ($keys as $key) {
@@ -277,7 +240,7 @@ private function collectHistograms()
 
     private function collectGauges()
     {
-        $keys = $this->redis->sMembers(self::$prefix . Gauge::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
+        $keys = $this->redis->sMembers($this->prefix . Gauge::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
         sort($keys);
         $gauges = array();
         foreach ($keys as $key) {
@@ -303,7 +266,7 @@ private function collectGauges()
 
     private function collectCounters()
     {
-        $keys = $this->redis->sMembers(self::$prefix . Counter::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
+        $keys = $this->redis->sMembers($this->prefix . Counter::TYPE . self::PROMETHEUS_METRIC_KEYS_SUFFIX);
         sort($keys);
         $counters = array();
         foreach ($keys as $key) {
@@ -347,7 +310,6 @@ private function getRedisCommand($cmd)
      */
     private function toMetricKey(array $data)
     {
-        return implode(':', array(self::$prefix, $data['type'], $data['name']));
+        return implode(':', array($this->prefix, $data['type'], $data['name']));
     }
-
 }
diff --git a/src/Prometheus/Storage/RedisAdapter.php b/src/Prometheus/Storage/RedisAdapter.php
new file mode 100644
index 0000000..c7d16ad
--- /dev/null
+++ b/src/Prometheus/Storage/RedisAdapter.php
@@ -0,0 +1,119 @@
+<?php
+
+namespace Prometheus\Storage;
+
+use Predis\Client;
+use Prometheus\Exception\StorageException;
+
+class RedisAdapter
+{
+    /**
+     * @var \Redis|Client
+     */
+    private $redis;
+
+    private $options;
+
+    /**
+     * @param \Redis $redis
+     * @param array $options
+     * @return static
+     */
+    public static function forRedis(\Redis $redis, array $options = [])
+    {
+        $adapter = new self($redis);
+        $adapter->options = array_replace([
+            'host' => '127.0.0.1',
+            'port' => 6379,
+            'timeout' => 0.1,
+            'read_timeout' => 10,
+            'persistent_connections' => false,
+            'password' => null,
+        ], $options);
+
+        return $adapter;
+    }
+
+    /**
+     * @param Client $client
+     * @return RedisAdapter
+     */
+    public static function forPredis(Client $client)
+    {
+        return new self($client);
+    }
+
+    /**
+     * @param \Redis|Client $redisInstance
+     */
+    private function __construct($redisInstance)
+    {
+        $this->redis = $redisInstance;
+    }
+
+    /**
+     * @param string $script
+     * @param array $args
+     * @param int $numKeys
+     */
+    public function evaluate($script, $args = array(), $numKeys = 0)
+    {
+        if ($this->redis instanceof Client) {
+            $this->redis->eval($script, $numKeys, ...$args);
+            return;
+        }
+
+        $this->openConnection();
+        $this->redis->eval($script, $args, $numKeys);
+    }
+
+    /**
+     * @param string $key
+     * @return array
+     */
+    public function sMembers($key)
+    {
+        $this->openConnection();
+        return $this->redis->smembers($key);
+    }
+
+    /**
+     * @param string $key
+     * @return array
+     */
+    public function hGetAll($key)
+    {
+        $this->openConnection();
+        return $this->redis->hgetall($key);
+    }
+
+    public function flushAll()
+    {
+        $this->openConnection();
+        $this->redis->flushall();
+    }
+
+    /**
+     * @throws StorageException
+     */
+    private function openConnection()
+    {
+        if ($this->redis instanceof Client) {
+            return;
+        }
+
+        try {
+            if ($this->options['persistent_connections']) {
+                @$this->redis->pconnect($this->options['host'], $this->options['port'], $this->options['timeout']);
+            } else {
+                @$this->redis->connect($this->options['host'], $this->options['port'], $this->options['timeout']);
+            }
+            if ($this->options['password']) {
+                $this->redis->auth($this->options['password']);
+            }
+            $this->redis->setOption(\Redis::OPT_READ_TIMEOUT, $this->options['read_timeout']);
+        } catch (\RedisException $e) {
+            throw new StorageException("Can't connect to Redis server", 0, $e);
+        }
+    }
+}
\ No newline at end of file
diff --git a/tests/Test/Prometheus/Predis/CollectorRegistryTest.php b/tests/Test/Prometheus/Predis/CollectorRegistryTest.php
index 9bb836b..a6acda5 100644
--- a/tests/Test/Prometheus/Predis/CollectorRegistryTest.php
+++ b/tests/Test/Prometheus/Predis/CollectorRegistryTest.php
@@ -1,16 +1,10 @@
 <?php
 
-
 namespace Test\Prometheus\Predis;
 
-use Prometheus\Storage\Predis;
 use Test\Prometheus\AbstractCollectorRegistryTest;
 
 class CollectorRegistryTest extends AbstractCollectorRegistryTest
 {
-    public function configureAdapter()
-    {
-        $this->adapter = new Predis(new \Predis\Client(['host' => REDIS_HOST]));
-        $this->adapter->flushRedis();
-    }
+    use InitializationTrait;
 }
diff --git a/tests/Test/Prometheus/Predis/CounterTest.php b/tests/Test/Prometheus/Predis/CounterTest.php
index 7568ff6..3d2eb8c 100644
--- a/tests/Test/Prometheus/Predis/CounterTest.php
+++ b/tests/Test/Prometheus/Predis/CounterTest.php
@@ -1,9 +1,7 @@
 <?php
 
-
 namespace Test\Prometheus\Predis;
 
-use Prometheus\Storage\Predis;
 use Test\Prometheus\AbstractCounterTest;
 
 /**
@@ -11,10 +9,5 @@
  */
 class CounterTest extends AbstractCounterTest
 {
-
-    public function configureAdapter()
-    {
-        $this->adapter = new Predis(new \Predis\Client(['host' => REDIS_HOST]));
-        $this->adapter->flushRedis();
-    }
+    use InitializationTrait;
 }
diff --git a/tests/Test/Prometheus/Predis/GaugeTest.php b/tests/Test/Prometheus/Predis/GaugeTest.php
index fe14939..bb40755 100644
--- a/tests/Test/Prometheus/Predis/GaugeTest.php
+++ b/tests/Test/Prometheus/Predis/GaugeTest.php
@@ -1,9 +1,7 @@
 <?php
 
-
 namespace Test\Prometheus\Predis;
 
-use Prometheus\Storage\Predis;
 use Test\Prometheus\AbstractGaugeTest;
 
 /**
@@ -11,10 +9,5 @@
  */
 class GaugeTest extends AbstractGaugeTest
 {
-
-    public function configureAdapter()
-    {
-        $this->adapter = new Predis(new \Predis\Client(['host' => REDIS_HOST]));
-        $this->adapter->flushRedis();
-    }
+    use InitializationTrait;
 }
diff --git a/tests/Test/Prometheus/Predis/HistogramTest.php b/tests/Test/Prometheus/Predis/HistogramTest.php
index caa7397..a8a0fe8 100644
--- a/tests/Test/Prometheus/Predis/HistogramTest.php
+++ b/tests/Test/Prometheus/Predis/HistogramTest.php
@@ -1,9 +1,7 @@
 <?php
 
-
 namespace Test\Prometheus\Predis;
 
-use Prometheus\Storage\Predis;
 use Test\Prometheus\AbstractHistogramTest;
 
 /**
@@ -11,10 +9,5 @@
  */
 class HistogramTest extends AbstractHistogramTest
 {
-
-    public function configureAdapter()
-    {
-        $this->adapter = new Predis(new \Predis\Client(['host' => REDIS_HOST]));
-        $this->adapter->flushRedis();
-    }
+    use InitializationTrait;
 }
diff --git a/tests/Test/Prometheus/Predis/InitializationTrait.php b/tests/Test/Prometheus/Predis/InitializationTrait.php
new file mode 100644
index 0000000..b642984
--- /dev/null
+++ b/tests/Test/Prometheus/Predis/InitializationTrait.php
@@ -0,0 +1,17 @@
+<?php
+
+namespace Test\Prometheus\Predis;
+
+use Predis\Client;
+use Prometheus\Storage\Redis;
+
+trait InitializationTrait
+{
+    public function configureAdapter()
+    {
+        $this->adapter = Redis::usingPredis(
+            new Client(['host' => REDIS_HOST])
+        );
+        $this->adapter->flushRedis();
+    }
+}
diff --git a/tests/Test/Prometheus/Redis/CollectorRegistryTest.php b/tests/Test/Prometheus/Redis/CollectorRegistryTest.php
index ed2ad2b..7261005 100644
--- a/tests/Test/Prometheus/Redis/CollectorRegistryTest.php
+++ b/tests/Test/Prometheus/Redis/CollectorRegistryTest.php
@@ -1,16 +1,10 @@
 <?php
 
-
 namespace Test\Prometheus\Redis;
 
-use Prometheus\Storage\Redis;
 use Test\Prometheus\AbstractCollectorRegistryTest;
 
 class CollectorRegistryTest extends AbstractCollectorRegistryTest
 {
-    public function configureAdapter()
-    {
-        $this->adapter = new Redis(array('host' => REDIS_HOST));
-        $this->adapter->flushRedis();
-    }
+    use InitializationTrait;
 }
diff --git a/tests/Test/Prometheus/Redis/CounterTest.php b/tests/Test/Prometheus/Redis/CounterTest.php
index 0d78272..4e9bc15 100644
--- a/tests/Test/Prometheus/Redis/CounterTest.php
+++ b/tests/Test/Prometheus/Redis/CounterTest.php
@@ -1,9 +1,7 @@
 <?php
 
-
 namespace Test\Prometheus\Redis;
 
-use Prometheus\Storage\Redis;
 use Test\Prometheus\AbstractCounterTest;
 
 /**
@@ -11,10 +9,5 @@
  */
 class CounterTest extends AbstractCounterTest
 {
-
-    public function configureAdapter()
-    {
-        $this->adapter = new Redis(array('host' => REDIS_HOST));
-        $this->adapter->flushRedis();
-    }
+    use InitializationTrait;
 }
diff --git a/tests/Test/Prometheus/Redis/GaugeTest.php b/tests/Test/Prometheus/Redis/GaugeTest.php
index 17d0c44..952a259 100644
--- a/tests/Test/Prometheus/Redis/GaugeTest.php
+++ b/tests/Test/Prometheus/Redis/GaugeTest.php
@@ -1,9 +1,7 @@
 <?php
 
-
 namespace Test\Prometheus\Redis;
 
-use Prometheus\Storage\Redis;
 use Test\Prometheus\AbstractGaugeTest;
 
 /**
@@ -11,10 +9,5 @@
  */
 class GaugeTest extends AbstractGaugeTest
 {
-
-    public function configureAdapter()
-    {
-        $this->adapter = new Redis(array('host' => REDIS_HOST));
-        $this->adapter->flushRedis();
-    }
+    use InitializationTrait;
 }
diff --git a/tests/Test/Prometheus/Redis/HistogramTest.php b/tests/Test/Prometheus/Redis/HistogramTest.php
index 57f73f6..e95b0b0 100644
--- a/tests/Test/Prometheus/Redis/HistogramTest.php
+++ b/tests/Test/Prometheus/Redis/HistogramTest.php
@@ -1,9 +1,7 @@
 <?php
 
-
 namespace Test\Prometheus\Redis;
 
-use Prometheus\Storage\Redis;
 use Test\Prometheus\AbstractHistogramTest;
 
 /**
@@ -11,10 +9,5 @@
  */
 class HistogramTest extends AbstractHistogramTest
 {
-
-    public function configureAdapter()
-    {
-        $this->adapter = new Redis(array('host' => REDIS_HOST));
-        $this->adapter->flushRedis();
-    }
+    use InitializationTrait;
 }
diff --git a/tests/Test/Prometheus/Redis/InitializationTrait.php b/tests/Test/Prometheus/Redis/InitializationTrait.php
new file mode 100644
index 0000000..ffa5997
--- /dev/null
+++ b/tests/Test/Prometheus/Redis/InitializationTrait.php
@@ -0,0 +1,17 @@
+<?php
+
+namespace Test\Prometheus\Redis;
+
+use Prometheus\Storage\Redis;
+
+trait InitializationTrait
+{
+    public function configureAdapter()
+    {
+        $this->adapter = Redis::usingRedis(
+            new \Redis(),
+            array('host' => REDIS_HOST)
+        );
+        $this->adapter->flushRedis();
+    }
+}
diff --git a/tests/Test/Prometheus/Storage/RedisTest.php b/tests/Test/Prometheus/Storage/RedisAdapterTest.php
similarity index 61%
rename from tests/Test/Prometheus/Storage/RedisTest.php
rename to tests/Test/Prometheus/Storage/RedisAdapterTest.php
index 8eb1654..0db173c 100644
--- a/tests/Test/Prometheus/Storage/RedisTest.php
+++ b/tests/Test/Prometheus/Storage/RedisAdapterTest.php
@@ -4,7 +4,7 @@
 namespace Prometheus\Storage;
 
 
-class RedisTest extends \PHPUnit_Framework_TestCase
+class RedisAdapterTest extends \PHPUnit_Framework_TestCase
 {
     /**
      * @test
@@ -13,8 +13,8 @@ class RedisTest extends \PHPUnit_Framework_TestCase
      */
     public function itShouldThrowAnExceptionOnConnectionFailure()
     {
-        $redis = new Redis(array('host' => 'doesntexist.test'));
-        $redis->flushRedis();
+        $redis = RedisAdapter::forRedis(new \Redis, ['host' => 'doesntexist.test']);
+        $redis->hGetAll('test');
     }
 
 }