RSolr::Ext

A set of helper methods/modules to assist in building Solr queries and handling responses when using the RSolr library.

Installation:

gem sources -a http://gemcutter.org
sudo gem install rsolr-ext

RSolr

Requests

To use the RSolr::Ext connection instead of the normal RSolr connection just require ‘rsolr-ext’:

require 'rsolr-ext'
solr = RSolr::Ext.connect

RSolr::Ext adds a #find and a #luke method to the connection object.

#luke

The #luke method returns a Hash/Mash result of a /admin/luke?numTerms=0 request:

luke_response = solr.luke
luke_response['index']
luke_response['fields']
luke_response['info']

#find

The #find method listens for certain keys. All other keys are ignored, allowing the ability to mix-and-match special keys with normal Solr param keys. The recognized keys are describe below.

:page - This maps to the Solr “start” param. The current “page” in the results set. RSolr::Ext handles the page-to-rows math for you.

:per_page - This maps to the Solr “rows” param. How many “pages” in the result.

:queries - This key maps to the Solr “q” param. Accepts a string, array or hash. When an array is used, each value is joined by a space. When a hash is used, the keys are used as Solr fields.

:queries => ‘normal’ BECOMES ?q=normal
:queries => [‘one’, ‘two’] BECOMES ?q=one two
:queries => :title=>‘one’ BECOMES ?q=title:(one)
:queries => [‘red’, :title=>‘one’] BECOMES ?q=red title:(one)

:phrases - This value is mapped to the Solr “q” param. When this key is used, the value will become double-quoted, creating a Solr “phrase” based query.

:phrases => ‘normal’ BECOMES ?q=“normal”
:phrases => [‘one’, ‘two’] BECOMES ?q=“one” “two”
:phrases => :title=>‘one’ BECOMES ?q=title:(“one”)
:phrases => [‘red’, :title=>‘one’] BECOMES ?q=“red” title:(“one”)

:filters - The :filters key maps to the Solr :fq param. This has the same behavior as the :queries key, except it’s for the :fq param.

:filters => ‘normal’ BECOMES ?fq=normal
:filters => [‘one’, ‘two’] BECOMES ?fq=one two
:filters => :title=>‘one’ BECOMES ?fq=title:(one)
:filters => [‘red’, :title=>‘one’] BECOMES ?fq=red title:(one)

:phrase_filters - The :phrase_filters key maps to the Solr :fq param. This has the same behavior as the :phrases key, except it’s for the :fq param.

:phrase_filters => ‘normal’ BECOMES ?fq=“normal”
:phrase_filters => [‘one’, ‘two’] BECOMES ?fq=“one” “two”
:phrase_filters => :title=>‘one’ BECOMES ?fq=title:(“one”)
:phrase_filters => [‘red’, :title=>‘one’] BECOMES ?fq=“red” title:(“one”)

:facets - The :facets does a few different things. First, it sets the Solr param facet=true. It accepts a hash with a single key called :fields. This should be an array of field names to facet on.

:facets=>‘blah’] BECOMES ?facet=true&facet.field=cat&facet.field=blah

Request Example

require 'rsolr-ext'
solr = RSolr::Ext.connect
solr_params = {
  :page=>2,
  :per_page=>10,
  :phrases=>{:name=>'This is a phrase'},
  :filters=>['test', {:price=>(1..10)}],
  :phrase_filters=>{:manu=>['Apple']},
  :queries=>'ipod',
  :facets=>{:fields=>['cat', 'blah']},
  :echoParams => 'EXPLICIT'
}
response = rsolr.find solr_params, :method => :post

Responses

RSolr::Ext decorates the normal output hash from RSolr and adds some helpful methods.

require 'rsolr-ext'
solr = RSolr::Ext.connect

response = solr.find :q=>'*:*'

response.ok?
response.params
response.docs
response.docs.previous_page
response.docs.next_page
response.facets.each do |facet|
  puts facet.name
  facet.items.each do |item|
    puts "#{facet.name}::#{item.value} (#{item.hits})"
  end
end

You can access values in the response hash using symbols or strings.

Documents/Pagination

If you wanna paginate the documents:

<%= will_paginate response.docs.will_paginate %>

The “Model” Module

You can create your own <read-only> “models” using RSolr::Ext::Model

class Book
  include RSolr::Ext::Model
  def self.find_by_author(author)
      find(:fq=>'object_type:"book"', :rows=>10, :phrase_filters=>{:author=>author})
  end
end

all_books = Book.find('*:*')
hawk_books = Book.find_by_author('hawk')