README

Toper is a PHP Rest client based on popular Guzzle Rest Client. It base responsibility is to perform tasks connected with a load balancing and a fault tolerance.

Many modern web applications to keep up with a huge traffic needs to connect to not one backend machine, but often to several identical machines. Toper allows you to implement this very fast and simply. The main goal of Toper is to watch service instances and if any of them failed Toper will switch to other one.

Features

• Round robin
• Fault tolerance

Installing via Composer

The recomended way to intall toper is using Composer

#install composer
curl -sS https://getcomposer.org/installer | php

Edit your composer.json file and add Toper to require section:

{
    "require": {
        "allegro/toper": "dev-master"
    }
}

Quick start

Here is example how create a request by Toper. In this case Toper is configured to use multiple destinations to protect against a breakdown if any of them fail.

<?php

use Toper\GuzzleClientFactory;
use Toper\StaticHostPoolProvider;

$hostPollProvider = new StaticHostPoolProvider(
    array("http://service1.com", "http://service2.com")
);
$guzzleClientFactory = new GuzzleClientFactory();

$toper = new \Toper\Client($hostPollProvider, $guzzleClientFactory);
$response = $toper->get('/')
    ->addHeader('cache-control', 'no-cache')
    ->send();

if($response->getStatusCode() == 200) {
    echo $response->getBody();
}

Host Cache

If you are using an external service to provide actually enabled applications hosts then maybe it is not efficiently to call every time this service before make a request to the target service. Better solution is to cache result from this service for some period time. That why we provide ChaceHostPoolProvider which can decorate your base pool provider and cache a result for configured time.

<?php

class MyHostPoolProvider implements \Toper\HostPoolProviderInterface
{
    /**
     * @return \Toper\HostPoolInterface
     */
    public function get()
    {
        //fetch hosts code
    }
}

$storage = new \Toper\Storage\FileStorage(
    "/tmp/"
);

$cacheLifeTime = 5; //time in seconds

$cachedHostProvider = new \Toper\CachedHostPoolProvider(
    new MyHostPoolProvider(), $storage, new \Toper\Clock(), $cacheLifeTime

License

Copyright 2014 Grupa Allegro

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.