module ThinkingSphinx
class Index
# The Builder class is the core for the index definition block processing.
# There are four methods you really need to pay attention to:
# - indexes (aliased to includes and attribute)
# - has (aliased to attribute)
# - where
# - set_property (aliased to set_properties)
#
# The first two of these methods allow you to define what data makes up
# your indexes. #where provides a method to add manual SQL conditions, and
# set_property allows you to set some settings on a per-index basis. Check
# out each method's documentation for better ideas of usage.
#
class Builder
class << self
# No idea where this is coming from - haven't found it in any ruby or
# rails documentation. It's not needed though, so it gets undef'd.
# Hopefully the list of methods that get in the way doesn't get too
# long.
undef_method :parent
attr_accessor :fields, :attributes, :properties, :conditions
# Set up all the collections. Consider this the equivalent of an
# instance's initialize method.
#
def setup
@fields = []
@attributes = []
@properties = {}
@conditions = []
end
# This is how you add fields - the strings Sphinx looks at - to your
# index. Technically, to use this method, you need to pass in some
# columns and options - but there's some neat method_missing stuff
# happening, so lets stick to the expected syntax within a define_index
# block.
#
# Expected options are :as, which points to a column alias in symbol
# form, and :sortable, which indicates whether you want to sort by this
# field.
#
# Adding Single-Column Fields:
#
# You can use symbols or methods - and can chain methods together to
# get access down the associations tree.
#
# indexes :id, :as => :my_id
# indexes :name, :sortable => true
# indexes first_name, last_name, :sortable => true
# indexes users.posts.content, :as => :post_content
# indexes users(:id), :as => :user_ids
#
# Keep in mind that if any keywords for Ruby methods - such as id or
# name - clash with your column names, you need to use the symbol
# version (see the first, second and last examples above).
#
# If you specify multiple columns (example #2), a field will be created
# for each. Don't use the :as option in this case. If you want to merge
# those columns together, continue reading.
#
# Adding Multi-Column Fields:
#
# indexes [first_name, last_name], :as => :name
# indexes [location, parent.location], :as => :location
#
# To combine multiple columns into a single field, you need to wrap
# them in an Array, as shown by the above examples. There's no
# limitations on whether they're symbols or methods or what level of
# associations they come from.
#
# Adding SQL Fragment Fields
#
# You can also define a field using an SQL fragment, useful for when
# you would like to index a calculated value.
#
# indexes "age < 18", :as => :minor
#
def indexes(*args)
options = args.extract_options!
args.each do |columns|
columns = FauxColumn.new(columns) if columns.is_a?(Symbol)
fields << Field.new(columns, options)
if fields.last.sortable
attributes << Attribute.new(
fields.last.columns.collect { |col| col.clone },
options.merge(
:type => :string,
:as => fields.last.unique_name.to_s.concat("_sort").to_sym
)
)
end
end
end
alias_method :field, :indexes
alias_method :includes, :indexes
# This is the method to add attributes to your index (hence why it is
# aliased as 'attribute'). The syntax is the same as #indexes, so use
# that as starting point, but keep in mind the following points.
#
# An attribute can have an alias (the :as option), but it is always
# sortable - so you don't need to explicitly request that. You _can_
# specify the data type of the attribute (the :type option), but the
# code's pretty good at figuring that out itself from peering into the
# database.
#
# Attributes are limited to the following types: integers, floats,
# datetimes (converted to timestamps), booleans and strings. Don't
# forget that Sphinx converts string attributes to integers, which are
# useful for sorting, but that's about it.
#
# You can also have a collection of integers for multi-value attributes
# (MVAs). Generally these would be through a has_many relationship,
# like in this example:
#
# has posts(:id), :as => :post_ids
#
# This allows you to filter on any of the values tied to a specific
# record. Might be best to read through the Sphinx documentation to get
# a better idea of that though.
#
# Adding SQL Fragment Attributes
#
# You can also define an attribute using an SQL fragment, useful for
# when you would like to index a calculated value. Don't forget to set
# the type of the attribute though:
#
# indexes "age < 18", :as => :minor, :type => :boolean
#
# If you're creating attributes for latitude and longitude, don't
# forget that Sphinx expects these values to be in radians.
#
def has(*args)
options = args.extract_options!
args.each do |columns|
columns = case columns
when Symbol, String
FauxColumn.new(columns)
when Array
columns.collect { |col|
case col
when Symbol, String
FauxColumn.new(col)
else
col
end
}
else
columns
end
attributes << Attribute.new(columns, options)
end
end
alias_method :attribute, :has
# Use this method to add some manual SQL conditions for your index
# request. You can pass in as many strings as you like, they'll get
# joined together with ANDs later on.
#
# where "user_id = 10"
# where "parent_type = 'Article'", "created_at < NOW()"
#
def where(*args)
@conditions += args
end
# This is what to use to set properties on the index. Chief amongst
# those is the delta property - to allow automatic updates to your
# indexes as new models are added and edited - but also you can
# define search-related properties which will be the defaults for all
# searches on the model.
#
# set_property :delta => true
# set_property :field_weights => {"name" => 100}
#
# Also, the following two properties are particularly relevant for
# geo-location searching - latitude_attr and longitude_attr. If your
# attributes for these two values are named something other than
# lat/latitude or lon/long/longitude, you can dictate what they are
# when defining the index, so you don't need to specify them for every
# geo-related search.
#
# set_property :latitude_attr => "lt", :longitude => "lg"
#
# Please don't forget to add a boolean field named 'delta' to your
# model's database table if enabling the delta index for it.
#
def set_property(*args)
options = args.extract_options!
if options.empty?
@properties[args[0]] = args[1]
else
@properties.merge!(options)
end
end
alias_method :set_properties, :set_property
# Handles the generation of new columns for the field and attribute
# definitions.
#
def method_missing(method, *args)
FauxColumn.new(method, *args)
end
end
end
end
end