Configuration.md

#Configuration

##Initial YML Configuration The first step is to enable the Elastic Search service. To do this, the standard configuration system is used. The simplest default configuration (e.g. in mysite/_config/elastica.yml) is:

	Injector:
	  SilverStripe\Elastica\ElasticaService:
		constructor:
		  - %$Elastica\Client
		  - YOUR_INDEX_NAME

Change YOUR_INDEX_NAME to a more meaningful name.

For any SilverStripe DataObject, be it SiteTree related or not, it can be made searchable by adding the extension SilverStripe\Elastica\Searchable and configuring which fields are actually searchable.

The following configuration allows all pages within the CMS to be searchable, as well as Members. Edit a config file such as mysite/_config/searchable-elastica.yml and run dev/build as normal:

	SiteTree:
	  extensions:
		- 'SilverStripe\Elastica\Searchable'
	Member:
	  extensions:
		- 'SilverStripe\Elastica\Searchable'

Elasticsearch can then be interacted with by using the SilverStripe\Elastica\ElasticService class.

##PHP Level Configuration ###Searchable Fields Adding searchable fields to an object simply involved add a static variable $searchable_fields containing an array of the fields that are to be searchable. Elasticsearch will attempt to determine their types, but if this needs changed it can be done so via an extension.

###Searchable Relationships Similar to the above, relationships of types has_one, one_to_many, and many_to_many can have their searchable fields stored as a flat array in the document being indexed. These are indicated using a static variable $searchable_relationships, with optionally a pair of brackets '()' appended to the method name, just to make clearer in the configuration that a method is being used. Note that relationships are only followed one level deep, this is to avoid a situation where infinite recursion occurs, and so as also not to bloat the elasticsearch document size excessively.

###Autocomplete Fields Autocomplete, or 'find as you type', fields attempt to find search results whilst text is entered into a search field. In order for the search to be fast the indexing of terms is verbose, as such only enable this option for short fields such as a person's name or the title of a page.

After every change in the searchable fields for a Dataobject the task SilverStripe-Elastica-ReindexTask should be executed. See Tasks.

###Purely PHP

class YourPage extends Page
{
	private static $db = array(
		"YourField1" => "Varchar(255)",
		"YourField2"  => "Varchar(255)"
	);

	private static $many_many = array('Tags' => 'Tag');

	private static $searchable_fields = array(
		"YourField1",
		"YourField2"
	);

	private static $searchable_autocomplete = array('Title');

	// example where this content type has related tags
	private static $searchable_relationships = array(
		'Tags()'
	);
}

###PHP and YML Static variables in SilverStripe classes can be configured in YML files. This is the preferred way to configure indexable fields on a class, as it means third-party module classes can have fields made searchable without altering any module code.

class YourPage extends Page
{
	private static $db = array(
		"YourField1" => "Varchar(255)",
		"YourField2"  => "Varchar(255)"
	);
}

Add the following to a suitable YML file using standard configuration.

YourPage:
  searchable_fields:
	- YourField1
	- YourField2
	- Title
  searchable_relationships:
    - Tags()
  searchable_autocomplete:
    - Title

##Index Invalidation In the case of an item indexed through a relationship, if that item changes the original items needs to be invalidated. This is a TODO, currently - the only current workaround is to reindex.