README

A Simple Search Engine in PHP

• Query the document index using multi word queries.
• Search result is ranked with TF-IDF term weighting and cosine similarity.
• Uses MongoDB, MySQL or SQLite to store the documents.
• Stores the search index in Memcached or MongoDB.
• Easily extensible to support other storage providers.
• Uses Snowball- or Porter-stemming of tokens.

NOTE: this project is still in development

Install

$ composer require markusos/simple-search dev-master

When running the Search Engine make sure that the MongoDB and Memcached processes are running on the server.

System Requirements

You need PHP >= 5.4.0 to use markusos\simple-search but the latest stable version of PHP is recommended.

If you want to use the MongoDB storage and/or index providers, you need to install the mongo extension.

$ pecl install mongo

To use the snowball stemmer you also need to install the stem extension.

$ pecl install stem

Make sure that you install the languages that you need when installing the stem extension.

Usage

Basic usage

Index document:

<?php 

$document = new Search\Document(
    'Test Title',
    'This is a test document with some content to be searchable.'
    );

$engine = new Search\Engine();
$engine->addDocument($document);

Search:

<?php 

$engine = new Search\Engine();
$result = $engine->search('test document');

Custom setup

The search engine supports customization by exchangeable service providers. When initializing the search engine it is possible to switch out the default implementations and provide your own.

<?php 

$config = Search\Config\Config::createBuilder()
                ->tokenizer($tokenizer)
                ->store($store)
                ->index($index)
                ->ranker($ranker)
                ->stopWords($stopWords)
                ->build();
                
$engine = new Search\Engine($config);

Or you can use the default and override the settings you need:

<?php 

$config = Search\Config\Config::createBuilder()
                ->defaultConfig()
                ->stopWords(['new', 'list', 'of', 'stop', 'words'])
                ->build();
                
$engine = new Search\Engine($config);

Testing

Simple Search has a PHPUnit test suite. To run the tests, run the following command from the project folder:

$ phpunit

If you don't want to run the integration tests that require Memcached and MongoDB to be started, simply run:

$ phpunit --testsuite unit

License

The MIT License (MIT)

Copyright (c) 2015 Markus Östberg