# Contains methods to use in views and helpers.
module MetaTags
module ViewHelper
# Set meta tags for the page.
#
# Method could be used several times, and all options passed will
# be merged. If you will set the same property several times, last one
# will take precedence.
#
# Examples:
# set_meta_tags :title => 'Login Page', :description => 'Here you can login'
# set_meta_tags :keywords => 'authorization, login'
#
# Usually you will not call this method directly. Use +title+, +keywords+,
# +description+ for your daily tasks.
#
# See +display_meta_tags+ for allowed options.
def set_meta_tags(meta_tags = {})
@meta_tags ||= {}
@meta_tags.merge!(meta_tags || {})
end
# Set the page title and return it back.
#
# This method is best suited for use in helpers. It sets the page title
# and returns it (or +headline+ if specified).
#
# Examples:
# <%= title 'Login Page' %> => title='Login Page', return='Login Page'
# <%= title 'Login Page', 'Please login' %> => title='Login Page', return='Please Login'
#
# You can specify +title+ as a string or array:
# title :title => ['part1', 'part2']
# # part1 | part2
def title(title, headline = '')
set_meta_tags(:title => title)
headline.blank? ? title : headline
end
# Set the page keywords.
#
# Keywords can be passed as string of comma-separated values, or as an array:
#
# set_meta_tags :keywords => ['tag1', 'tag2']
# # tag1, tag2
#
# Examples:
# <% keywords 'keyword1, keyword2' %>
# <% keywords %w(keyword1 keyword2) %>
def keywords(keywords)
set_meta_tags(:keywords => keywords)
keywords
end
# Set the page description.
#
# Description is a string (HTML will be stripped from output string).
#
# Examples:
# <% description 'This is login page' %>
def description(description)
set_meta_tags(:description => description)
description
end
# Set the noindex meta tag
#
# You can specify noindex as a boolean or string
#
# Examples:
# <% noindex true %>
# <% noindex 'googlebot' %>
def noindex(noindex)
set_meta_tags(:noindex => noindex)
noindex
end
# Set the nofollow meta tag
#
# You can specify nofollow as a boolean or string
#
# Examples:
# <% nofollow true %>
# <% nofollow 'googlebot' %>
def nofollow(nofollow)
set_meta_tags(:nofollow => nofollow)
nofollow
end
# Set default meta tag values and display meta tags.
#
# This method should be used in layout file.
#
# Examples:
#
# <%= display_meta_tags :site => 'My website' %>
#
#
# Allowed options:
# * :site -- site title;
# * :title -- page title;
# * :description -- page description;
# * :keywords -- page keywords;
# * :prefix -- text between site name and separator;
# * :separator -- text used to separate website name from page title;
# * :suffix -- text between separator and page title;
# * :lowercase -- when true, the page name will be lowercase;
# * :reverse -- when true, the page and site names will be reversed;
# * :noindex -- add noindex meta tag; when true, 'robots' will be used, otherwise the string will be used;
# * :nofollow -- add nofollow meta tag; when true, 'robots' will be used, otherwise the string will be used.
def display_meta_tags(default = {})
meta_tags = (default || {}).merge(@meta_tags || {})
# Prefix (leading space)
if meta_tags[:prefix]
prefix = meta_tags[:prefix]
elsif meta_tags[:prefix] === false
prefix = ''
else
prefix = ' '
end
# Separator
unless meta_tags[:separator].blank?
separator = meta_tags[:separator]
else
separator = '|'
end
# Suffix (trailing space)
if meta_tags[:suffix]
suffix = meta_tags[:suffix]
elsif meta_tags[:suffix] === false
suffix = ''
else
suffix = ' '
end
# Title
title = meta_tags[:title]
if meta_tags[:lowercase] === true
title = title.downcase unless title.blank?
end
# title
if title.blank?
result = content_tag :title, meta_tags[:site]
else
title = normalize_title(title)
title = [meta_tags[:site]] + title
title.reverse! if meta_tags[:reverse] === true
sep = prefix + separator + suffix
result = content_tag(:title, title.join(sep))
end
# description
description = normalize_description(meta_tags[:description])
result << "\n" + tag(:meta, :name => :description, :content => description) unless description.blank?
# keywords
keywords = normalize_keywords(meta_tags[:keywords])
result << "\n" + tag(:meta, :name => :keywords, :content => keywords) unless keywords.blank?
# noindex & nofollow
noindex_name = meta_tags[:noindex].is_a?(String) ? meta_tags[:noindex] : 'robots'
nofollow_name = meta_tags[:nofollow].is_a?(String) ? meta_tags[:nofollow] : 'robots'
if noindex_name == nofollow_name
content = [(meta_tags[:noindex] ? 'noindex' : nil), (meta_tags[:nofollow] ? 'nofollow' : nil)].compact.join(', ')
result << "\n" + tag(:meta, :name => noindex_name, :content => content) unless content.blank?
else
result << "\n" + tag(:meta, :name => noindex_name, :content => 'noindex') if meta_tags[:noindex]
result << "\n" + tag(:meta, :name => nofollow_name, :content => 'nofollow') if meta_tags[:nofollow]
end
return result
end
private
def normalize_title(title)
if title.is_a? String
title = [title]
end
title.map { |t| h(strip_tags(t)) }
end
def normalize_description(description)
return '' unless description
truncate(strip_tags(description).gsub(/\s+/, ' '), :length => 200)
end
def normalize_keywords(keywords)
return '' unless keywords
keywords = keywords.flatten.join(', ') if keywords.is_a?(Array)
strip_tags(keywords).mb_chars.downcase
end
end
end