class Allmusic

Allmusic.com client

@param [String]

Constants

ARTIST_SEARCH_URL

Public Class Methods

new( artist = nil, album = nil ) click to toggle source

# File lib/allmusic.rb, line 16
def initialize( artist = nil, album = nil )
  @artist = artist
  @album  = album
  @metadata = get_metadata( @artist, @album )
end

Public Instance Methods

genres() click to toggle source

# File lib/allmusic.rb, line 22
def genres
  return @metadata[:genres]
end

styles() click to toggle source

# File lib/allmusic.rb, line 26
def styles
  return @metadata[:styles]
end

Private Instance Methods

best_match(target, candidates) click to toggle source

@return [URL] The candidate with the highest Jaro-Winkler distance from target @param target [String] the string to compare @param candidates [Array] array of Nokogiri <A> nodes

# File lib/allmusic.rb, line 102
def best_match(target, candidates)
  # TODO: replace with a proper array sort
  confidence = 0
  best_url = nil
  jarow = FuzzyStringMatch::JaroWinkler.create( :native )
  candidates.each do |candidate|
    title = candidate.text
    distance = jarow.getDistance(target, title)
    if distance > confidence
      confidence = distance
      best_url = candidate['href']
    end
  end
  return best_url
end

get_metadata( artist, album ) click to toggle source

Sets @genre and @style for @album, @artist

# File lib/allmusic.rb, line 46
def get_metadata( artist, album )
  metadata = {:genres => [], :styles => []}
  # search for artist page e.g. http://www.allmusic.com/search/artists/abba
  artist_search_url = make_url(ARTIST_SEARCH_URL, artist)
  artist_search_page = nil
  begin
    artist_search_page = Nokogiri::HTML(open(artist_search_url))
  rescue
    return metadata
  end

  if no_search_result?(artist_search_page)
    return metadata
  end

  # get the url of the artist page
  artist_urls = artist_search_page.xpath("//ul[@class='search-results']//div[@class='name']/a")
  artist_url = best_match(artist, artist_urls)

  # get the artist discography page
  album_search_page = make_url(artist_url, '/discography/all')
  artist_discography_page = Nokogiri::HTML(open(album_search_page))

  # get album link
  album_urls = artist_discography_page.xpath("//td[@class='title']/a[1]")
  album_url = best_match(album, album_urls)

  unless album_url.nil?
    # get album page
    begin
      album_page = Nokogiri::HTML(open(album_url))
      metadata[:genres] = parse( album_page, 'genre' )
      metadata[:styles] = parse( album_page, 'styles')
    rescue
      return metadata
    end
  end
  return metadata
end

make_url( root, path) click to toggle source

@return [URL] Joins URL parts

# File lib/allmusic.rb, line 87
def make_url( root, path)
  # TODO: unsafe, not portable - File.join gives the wrong separator on windows
  # TODO: escape url
  clean_url = URI.escape(File.join(root, path))
  return clean_url
end

no_search_result?(page) click to toggle source

@return [true, false] Returns ‘true` if no search results for the given page

# File lib/allmusic.rb, line 95
def no_search_result?(page)
  return !page.xpath('//div[@class="no-results"]').empty?
end

parse( album_page, type = 'genre' ) click to toggle source

return a list of the albums genre/styles @param album_page [Nokogiri] the page node to parse @param type [String] ‘genre’ | ‘styles’ @return [string] list of genre / syles

# File lib/allmusic.rb, line 36
def parse( album_page, type = 'genre' )
  data = []
  data_nodes = album_page.xpath("//div[@class='#{type}']//a")
  data_nodes.each do |data_node|
    data << data_node.text
  end
  return data
end