Class: SemanticCrawler::Freebase::Country

Inherits:
Object
  • Object
show all
Includes:
HTTParty
Defined in:
lib/semantic_crawler/freebase/country.rb

Overview

Freebase Country entity. Currently it is very abstract and could be each entry on Freebase.

Constant Summary collapse

@@URI_PREFIX =

The URL prefix of an english Freebase RDF entity.

"http://rdf.freebase.com/rdf/en."
@@NAMESPACES =

Namespace hash

{
    "rdf" => "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
    "fb" => "http://rdf.freebase.com/ns/",
    "owl" => "http://www.w3.org/2002/07/owl#"
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(new_country_name) ⇒ Country

Creates a new Freebase object (JSON)



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# File 'lib/semantic_crawler/freebase/country.rb', line 24

def initialize(new_country_name)
    @country_name = new_country_name
    if !@country_name.nil?
        @normalized_country = @country_name.gsub(" ", "_").gsub("USA", "United_States_of_America").downcase
        @url = @@URI_PREFIX + @normalized_country
        @subject = "http://rdf.freebase.com/ns/en.#{@normalized_country}"
        @root_node = nil
        begin
            fetch_rdf
        rescue => e
            $log.error("Not able to get country information, through exception: #{e}")
        end
    end
end

Instance Attribute Details

#country_name ⇒ Object (readonly)

The read only country name



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# File 'lib/semantic_crawler/freebase/country.rb', line 21

def country_name
  @country_name
end

Instance Method Details

#administrative_divisions ⇒ Array<String>

Extract fb:location.country.administrative_divisions properties

Returns:

  • (Array<String>) 


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# File 'lib/semantic_crawler/freebase/country.rb', line 67

def administrative_divisions
    return_list = []
    list = query_root_node("fb:location.country.administrative_divisions/@rdf:resource", @@NAMESPACES)
    if !list.nil?
        list.each do |entry|
            return_list << entry.to_s
        end
    end
    return_list
end

#agencies ⇒ Array<String>

Extract fb:government.governmental_jurisdiction.agencies

Returns:

  • (Array<String>) —

    Returns the governmental jurisdiction agencies as URLs



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# File 'lib/semantic_crawler/freebase/country.rb', line 80

def agencies
    return_list = []
    list = query_root_node("fb:government.governmental_jurisdiction.agencies/@rdf:resource", @@NAMESPACES)
    if !list.nil?
        list.each do |entry|
            return_list << entry.to_s
        end
    end
    return_list
end

#contains ⇒ Array<String>

Extract the fb:location.location.contains properties

Returns:

  • (Array<String>) 


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# File 'lib/semantic_crawler/freebase/country.rb', line 54

def contains
    return_list = []
    list = query_root_node("fb:location.location.contains/@rdf:resource", @@NAMESPACES)
    if !list.nil?
        list.each do |entry|
            return_list << entry.to_s
        end
    end
    return_list
end

#object_name(lang = "en") ⇒ String

Extract the fb:type.object.name property

Parameters:

  • The (String) —

    language in ISO 3166-1 alpha-2 format

Returns:

  • (String) —

    The country name



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# File 'lib/semantic_crawler/freebase/country.rb', line 48

def object_name(lang = "en")
    query_root_node("fb:type.object.name[@xml:lang='#{lang}']/text()", @@NAMESPACES).to_s
end

#query_root_node(xpath_query, namespaces = {}) ⇒ String

Executes a xpath query with optional a hash with namespaces

Returns:

  • (String) 


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# File 'lib/semantic_crawler/freebase/country.rb', line 106

def query_root_node(xpath_query, namespaces = {})
    if !@root_node.nil?
        @root_node.xpath(xpath_query, namespaces)
    end
end

#same_as ⇒ Array<String>

Extract the owl:sameAs links

Returns:

  • (Array<String>) —

    A list of same concept URLs, e.g. to dbpedia or nytimes



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# File 'lib/semantic_crawler/freebase/country.rb', line 93

def same_as
    return_list = []
    list = query_root_node("owl:sameAs/@rdf:resource", @@NAMESPACES)
    if !list.nil?
        list.each do |entry|
            return_list << entry.to_s
        end
    end
    return_list
end

#website ⇒ String

Extract the fb:common.topic.topical_webpage property

Returns:

  • (String) —

    Website as String



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# File 'lib/semantic_crawler/freebase/country.rb', line 41

def website
    query_root_node("fb:common.topic.topical_webpage/text()", @@NAMESPACES).to_s
end

#xml_document ⇒ String

Outputs the document as XML

Returns:

  • (String) —

    The document serialized as XML



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# File 'lib/semantic_crawler/freebase/country.rb', line 114

def xml_document
    @root_node.to_s
end