Using the library

After the initial set-up, we continue explaining how to get started with the MongoDB driver and library for HHVM to write our first project.

PHP Library (PHPLIB)

The last thing we still need to install to get started on the application itself, is the PHP library.

The library needs to be installed with Composer. In your project directory (/var/www/html/my-first-project) type:

curl -sS https://getcomposer.org/installer -o installer.php
hhvm installer.php
rm installer.php

This downloads and installs Composer. Wherever it says "Use it: php composer.phar", it of course means hhvm composer.phar.

With Composer installed, we can now install the library:

hhvm composer.phar require mongodb/mongodb

It outputs something akin to:

Using version ^0.2.0 for mongodb/mongodb
./composer.json has been created
Loading composer repositories with package information
Updating dependencies (including require-dev)
  - Installing mongodb/mongodb (0.2.0)
 Downloading: 100%         

Writing lock file
Generating autoload files

And it has created several files (composer.json, composer.lock) as well as the vendor directory that contains the library.

Using the Library

Composer manages your dependencies, and will provide you with a loader that you include with the following at the start of your script:


<?php
    require 'vendor/autoload.php';

With this done, you can now use any of the functionality as described in the » documentation.

If you are familiar with the old driver, it should look too much out of place. The only big difference is that the » Database class is only used for Database specific operations. The » CRUD operations on the » Collection class are also renamed for clarity, and to be in accordance with a new language-agnostic » specification.

As an example, this is how you insert a document into the beers collection of the demo database:


<?php
    require 'vendor/autoload.php'; // include Composer goodies

    $manager = new MongoDB\Driver\Manager("mongodb://localhost:27017");
    $collection = new MongoDB\Collection($manager, "demo.beers");

    $result = $collection->insertOne( [ 'name' => 'Hinterland', 'brewery' => 'BrewDog' ] );

    echo "Inserted with Object ID '{$result->getInsertedId()}'";
    ?>

Instead of the original document being modified to add the newly generated _id field, this is now part of the result that comes back from the insertOne method.

After insertion, you can of course also query the data that you have just inserted. For that, you use the find method which returns a cursor that you can iterate over:


<?php
    require 'vendor/autoload.php'; // include Composer goodies

    $manager = new MongoDB\Driver\Manager("mongodb://localhost:27017");
    $collection = new MongoDB\Collection($manager, "demo.beers");

    $result = $collection->find( [ 'name' => 'Hinterland', 'brewery' => 'BrewDog' ] );

    foreach ($result as $entry)
    {
        echo $entry->_id, ': ', $entry->name, "\n";
    }
    ?>

You might have noticed that instead of accessing the _id and name fields is no longer done through an array access operator. Instead, they are now properties of a stdClass object. You can find more information on how serialisation and deserialisation between PHP variables and the BSON stored in MongoDB in the Persisting Data specification.