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sfLucenePlugin - 0.0.4sfLucene instantly adds a search engine to your application. |
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sfLucenePlugin integrates symfony and Zend Search Lucene to instantly add a search engine to your application. The plugin will auto-detect your ORM layer, but currently only supports Propel. (A Doctrine port is coming.)
Install the plugin:
symfony plugin-install http://plugins.symfony-project.com/sfLucenePlugin
Initialize configuration files:
symfony lucene-init myapp
Clear the cache
symfony cc
Configure sfLucene per the instructions below.
The entire plugin is configured by search.yml files placed throughout your application. You must be careful that you are aware of what search.yml file you are working in because each one has a different purpose. As you will later learn, the project level search.yml file controls the entire engine while a module's search.yml defines indexing parameters.
Open your project's search.yml file, located in myproject/config/search.yml. If you followed the installation instructions above, you will see at the bottom:
index:
name: MyIndex
encoding: UTF-8
Enter a name for the index. This is used internally by the plugin and does not matter much. If you require a different encoding to be used, enter it. Note, however, that UTF-8 is generally the best charset to store your indexes in.
If you require i18n support, you must define the cultures that you support under index. Use the following syntax:
index:
cultures: [fr_FR](en_US,)
By default, the plugin will not index or search on common words, such as "the" and "a". Further, it ignores single characters. If you require different behavior, you can define them like so:
index:
stop_words: [an, it](the,)
short_words: 2
sfLucene currently supports two ways to add information to the index: 1. Through the ORM layer 2. Through symfony actions
Through the ORM layer is the recommended method to add information to the index. The plugin can keep the index synchronized if you use the ORM layer. Through symfony actions is intended only for static content, such as the privacy policy.
Open your project's search.yml file and you will find a model declaration towards the top. This is where you put the models you wish to index. For each model, you define the fields you want to index and other parameters. The syntax is:
models:
BlogPost:
fields:
id: unindexed
title:
boost: 1.5
type: text
content: unstored
description: text
BlogComment:
fields:
id: unindexed
summary: text
message: text
description: message
title: summary
In the above example, two models are set to index: BlogPost and BlogComment. In BlogPost, the fields title, content, and description are stored, but the title fields holds the most weight with a boost factor of 1.5.
When search results are displayed, the system intelligently guesses which field should be displayed as the result "title" and which field is the result "description." However, to be explicit, you can specify a description and title field, as in BlogComment.
Note that the fields do not have to exist in your database. As long as it has a getter, you can use it in your index.
See the Zend_Search_Lucene documentation for more about the field types.
Next, you must tell your application where to route the model when it is returned. You do this by opening your application's config/search.yml file and defining a route:
models:
BlogPost:
route: blog/showPost?id={$id}
BlogComment:
route: blog/showComment?id={$id}
In routes, {$xxx} is a token and will be replaced by the appropriate field value. So, {$id} will be the value returned by the ->getId() method. Warning: You must also define the field in the project's search.yml to be indexed or unexpected results will occur!
Finally, you must register the model with the system. If you are using Propel, you must use Propel's behaviors.
You can do this by opening up the model's file and putting
sfPLuceneBehavior::getInitializer()->setupModel('MyModel');
after the class declaration. So, for a blog, you would open project/lib/model/BlogPost.php and append the above, replacing "!MyModel" with "!BlogPost".
To setup an action to be indexed, you must create a file in the module's config directory named search.yml. Inside this file, you define the actions you want indexed:
privacy:
tos:
security:
authenticated: true
credentials: [admin]
disclaimer:
params:
advanced: true
layout: true
As you can see, it is possible to define request parameters, manipulate authentication, and toggle decorating the response. By default, the response is not decorated, the user is not authenticated without any credentials, and there aren't any request parameters.
After you have defined the indexing parameters, you must build the initial index. You do this on the command line:
$ symfony lucene-rebuild myapp
replacing myapp with the name of your application you want to rebuild. This will build the index for all cultures.
sfLucene ships with a basic search interface that you can use in your application. Like the rest of the plugin, it is i18n ready and all you must do is define the translation phrases.
To enable the interface, open your application's settings.yml file and add "sfLucene" to the enabled_modules section:
all:
.settings:
enabled_modules: [sfLucene](default,)
You are free to define your own routes in the routing.yml file.
As every application is different, it is easy to customize the search interface to fit the look and feel of your site. Doing this is easy as all you must do is overload the templates and actions.
To get started, simply run the following on the command line:
$ symfony lucene-init-module myapp
If you look in myapp's module folder. you will see a new sfLucene module. Use this to customize your interface.
Often, when writing a search engine, you need to display a different result template for each model. For instance, a blog post should show differently than a forum post. You can easily customize your results by changing the "partial" value in your application's search.yml file. For example:
models:
BlogPost:
route: blog/showPost?slug={$slug}
partial: blog/searchResult
ForumPost:
route: forum/showThread?id={$id}
partial: forum/searchResult
The partial that you specify is given a $result object that you can use to build that result. The API for this object is pretty simple:
$result->getInternalTitle() returns the title of the search result.$result->getInternalRoute() returns the route to the search result.$result->getScore() returns the score / ranking of the search result.$result->getXXX() returns the XXX field.In addition to the $result object, it is also given a $query string, which was what the user searched for. This is useful for highlighting the results.
The plugin has an optional highlighter than will attempt to highlight keywords from searches. The highlighter will hook into this search engine and also attempts to hook into external search engines, such as Google and Yahoo!.
To enable this feature, open the application's config/filters.yml file and add the highlight filter before the cache filter:
rendering: ~
web_debug: ~
security: ~
# generally, you will want to insert your own filters here
highlight:
class: sfLuceneHighlightFilter
cache: ~
common: ~
flash: ~
execution: ~
By default, the highlighter will also attempt to display a notice to the user that automatic highlighting occured. The filter will search the result document for <!--[HIGHLIGHTER_NOTICE]--> and replace it with an i18n-ready notice (note: this is case sensitive).
To highlight a keyword, it must meet the following criteria: * must be X/HTML response content type * response must not be headers only * must not be an ajax request * be inside the
tag * be outside of