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Diffstat (limited to 'actionview/lib/action_view/helpers/asset_url_helper.rb')
| -rw-r--r-- | actionview/lib/action_view/helpers/asset_url_helper.rb | 470 |
1 files changed, 470 insertions, 0 deletions
diff --git a/actionview/lib/action_view/helpers/asset_url_helper.rb b/actionview/lib/action_view/helpers/asset_url_helper.rb new file mode 100644 index 0000000000..cc62783d60 --- /dev/null +++ b/actionview/lib/action_view/helpers/asset_url_helper.rb @@ -0,0 +1,470 @@ +# frozen_string_literal: true + +require "zlib" + +module ActionView + # = Action View Asset URL Helpers + module Helpers #:nodoc: + # This module provides methods for generating asset paths and + # URLs. + # + # image_path("rails.png") + # # => "/assets/rails.png" + # + # image_url("rails.png") + # # => "http://www.example.com/assets/rails.png" + # + # === Using asset hosts + # + # By default, Rails links to these assets on the current host in the public + # folder, but you can direct Rails to link to assets from a dedicated asset + # server by setting <tt>ActionController::Base.asset_host</tt> in the application + # configuration, typically in <tt>config/environments/production.rb</tt>. + # For example, you'd define <tt>assets.example.com</tt> to be your asset + # host this way, inside the <tt>configure</tt> block of your environment-specific + # configuration files or <tt>config/application.rb</tt>: + # + # config.action_controller.asset_host = "assets.example.com" + # + # Helpers take that into account: + # + # image_tag("rails.png") + # # => <img src="http://assets.example.com/assets/rails.png" /> + # stylesheet_link_tag("application") + # # => <link href="http://assets.example.com/assets/application.css" media="screen" rel="stylesheet" /> + # + # Browsers open a limited number of simultaneous connections to a single + # host. The exact number varies by browser and version. This limit may cause + # some asset downloads to wait for previous assets to finish before they can + # begin. You can use the <tt>%d</tt> wildcard in the +asset_host+ to + # distribute the requests over four hosts. For example, + # <tt>assets%d.example.com</tt> will spread the asset requests over + # "assets0.example.com", ..., "assets3.example.com". + # + # image_tag("rails.png") + # # => <img src="http://assets0.example.com/assets/rails.png" /> + # stylesheet_link_tag("application") + # # => <link href="http://assets2.example.com/assets/application.css" media="screen" rel="stylesheet" /> + # + # This may improve the asset loading performance of your application. + # It is also possible the combination of additional connection overhead + # (DNS, SSL) and the overall browser connection limits may result in this + # solution being slower. You should be sure to measure your actual + # performance across targeted browsers both before and after this change. + # + # To implement the corresponding hosts you can either setup four actual + # hosts or use wildcard DNS to CNAME the wildcard to a single asset host. + # You can read more about setting up your DNS CNAME records from your ISP. + # + # Note: This is purely a browser performance optimization and is not meant + # for server load balancing. See https://www.die.net/musings/page_load_time/ + # for background and https://www.browserscope.org/?category=network for + # connection limit data. + # + # Alternatively, you can exert more control over the asset host by setting + # +asset_host+ to a proc like this: + # + # ActionController::Base.asset_host = Proc.new { |source| + # "http://assets#{Digest::MD5.hexdigest(source).to_i(16) % 2 + 1}.example.com" + # } + # image_tag("rails.png") + # # => <img src="http://assets1.example.com/assets/rails.png" /> + # stylesheet_link_tag("application") + # # => <link href="http://assets2.example.com/assets/application.css" media="screen" rel="stylesheet" /> + # + # The example above generates "http://assets1.example.com" and + # "http://assets2.example.com". This option is useful for example if + # you need fewer/more than four hosts, custom host names, etc. + # + # As you see the proc takes a +source+ parameter. That's a string with the + # absolute path of the asset, for example "/assets/rails.png". + # + # ActionController::Base.asset_host = Proc.new { |source| + # if source.ends_with?('.css') + # "http://stylesheets.example.com" + # else + # "http://assets.example.com" + # end + # } + # image_tag("rails.png") + # # => <img src="http://assets.example.com/assets/rails.png" /> + # stylesheet_link_tag("application") + # # => <link href="http://stylesheets.example.com/assets/application.css" media="screen" rel="stylesheet" /> + # + # Alternatively you may ask for a second parameter +request+. That one is + # particularly useful for serving assets from an SSL-protected page. The + # example proc below disables asset hosting for HTTPS connections, while + # still sending assets for plain HTTP requests from asset hosts. If you don't + # have SSL certificates for each of the asset hosts this technique allows you + # to avoid warnings in the client about mixed media. + # Note that the +request+ parameter might not be supplied, e.g. when the assets + # are precompiled with the command `rails assets:precompile`. Make sure to use a + # +Proc+ instead of a lambda, since a +Proc+ allows missing parameters and sets them + # to +nil+. + # + # config.action_controller.asset_host = Proc.new { |source, request| + # if request && request.ssl? + # "#{request.protocol}#{request.host_with_port}" + # else + # "#{request.protocol}assets.example.com" + # end + # } + # + # You can also implement a custom asset host object that responds to +call+ + # and takes either one or two parameters just like the proc. + # + # config.action_controller.asset_host = AssetHostingWithMinimumSsl.new( + # "http://asset%d.example.com", "https://asset1.example.com" + # ) + # + module AssetUrlHelper + URI_REGEXP = %r{^[-a-z]+://|^(?:cid|data):|^//}i + + # This is the entry point for all assets. + # When using the asset pipeline (i.e. sprockets and sprockets-rails), the + # behavior is "enhanced". You can bypass the asset pipeline by passing in + # <tt>skip_pipeline: true</tt> to the options. + # + # All other asset *_path helpers delegate through this method. + # + # === With the asset pipeline + # + # All options passed to +asset_path+ will be passed to +compute_asset_path+ + # which is implemented by sprockets-rails. + # + # asset_path("application.js") # => "/assets/application-60aa4fdc5cea14baf5400fba1abf4f2a46a5166bad4772b1effe341570f07de9.js" + # + # === Without the asset pipeline (<tt>skip_pipeline: true</tt>) + # + # Accepts a <tt>type</tt> option that can specify the asset's extension. No error + # checking is done to verify the source passed into +asset_path+ is valid + # and that the file exists on disk. + # + # asset_path("application.js", skip_pipeline: true) # => "application.js" + # asset_path("filedoesnotexist.png", skip_pipeline: true) # => "filedoesnotexist.png" + # asset_path("application", type: :javascript, skip_pipeline: true) # => "/javascripts/application.js" + # asset_path("application", type: :stylesheet, skip_pipeline: true) # => "/stylesheets/application.css" + # + # === Options applying to all assets + # + # Below lists scenarios that apply to +asset_path+ whether or not you're + # using the asset pipeline. + # + # - All fully qualified URLs are returned immediately. This bypasses the + # asset pipeline and all other behavior described. + # + # asset_path("http://www.example.com/js/xmlhr.js") # => "http://www.example.com/js/xmlhr.js" + # + # - All assets that begin with a forward slash are assumed to be full + # URLs and will not be expanded. This will bypass the asset pipeline. + # + # asset_path("/foo.png") # => "/foo.png" + # + # - All blank strings will be returned immediately. This bypasses the + # asset pipeline and all other behavior described. + # + # asset_path("") # => "" + # + # - If <tt>config.relative_url_root</tt> is specified, all assets will have that + # root prepended. + # + # Rails.application.config.relative_url_root = "bar" + # asset_path("foo.js", skip_pipeline: true) # => "bar/foo.js" + # + # - A different asset host can be specified via <tt>config.action_controller.asset_host</tt> + # this is commonly used in conjunction with a CDN. + # + # Rails.application.config.action_controller.asset_host = "assets.example.com" + # asset_path("foo.js", skip_pipeline: true) # => "http://assets.example.com/foo.js" + # + # - An extension name can be specified manually with <tt>extname</tt>. + # + # asset_path("foo", skip_pipeline: true, extname: ".js") # => "/foo.js" + # asset_path("foo.css", skip_pipeline: true, extname: ".js") # => "/foo.css.js" + def asset_path(source, options = {}) + raise ArgumentError, "nil is not a valid asset source" if source.nil? + + source = source.to_s + return "" if source.blank? + return source if URI_REGEXP.match?(source) + + tail, source = source[/([\?#].+)$/], source.sub(/([\?#].+)$/, "") + + if extname = compute_asset_extname(source, options) + source = "#{source}#{extname}" + end + + if source[0] != ?/ + if options[:skip_pipeline] + source = public_compute_asset_path(source, options) + else + source = compute_asset_path(source, options) + end + end + + relative_url_root = defined?(config.relative_url_root) && config.relative_url_root + if relative_url_root + source = File.join(relative_url_root, source) unless source.starts_with?("#{relative_url_root}/") + end + + if host = compute_asset_host(source, options) + source = File.join(host, source) + end + + "#{source}#{tail}" + end + alias_method :path_to_asset, :asset_path # aliased to avoid conflicts with an asset_path named route + + # Computes the full URL to an asset in the public directory. This + # will use +asset_path+ internally, so most of their behaviors + # will be the same. If :host options is set, it overwrites global + # +config.action_controller.asset_host+ setting. + # + # All other options provided are forwarded to +asset_path+ call. + # + # asset_url "application.js" # => http://example.com/assets/application.js + # asset_url "application.js", host: "http://cdn.example.com" # => http://cdn.example.com/assets/application.js + # + def asset_url(source, options = {}) + path_to_asset(source, options.merge(protocol: :request)) + end + alias_method :url_to_asset, :asset_url # aliased to avoid conflicts with an asset_url named route + + ASSET_EXTENSIONS = { + javascript: ".js", + stylesheet: ".css" + } + + # Compute extname to append to asset path. Returns +nil+ if + # nothing should be added. + def compute_asset_extname(source, options = {}) + return if options[:extname] == false + extname = options[:extname] || ASSET_EXTENSIONS[options[:type]] + if extname && File.extname(source) != extname + extname + else + nil + end + end + + # Maps asset types to public directory. + ASSET_PUBLIC_DIRECTORIES = { + audio: "/audios", + font: "/fonts", + image: "/images", + javascript: "/javascripts", + stylesheet: "/stylesheets", + video: "/videos" + } + + # Computes asset path to public directory. Plugins and + # extensions can override this method to point to custom assets + # or generate digested paths or query strings. + def compute_asset_path(source, options = {}) + dir = ASSET_PUBLIC_DIRECTORIES[options[:type]] || "" + File.join(dir, source) + end + alias :public_compute_asset_path :compute_asset_path + + # Pick an asset host for this source. Returns +nil+ if no host is set, + # the host if no wildcard is set, the host interpolated with the + # numbers 0-3 if it contains <tt>%d</tt> (the number is the source hash mod 4), + # or the value returned from invoking call on an object responding to call + # (proc or otherwise). + def compute_asset_host(source = "", options = {}) + request = self.request if respond_to?(:request) + host = options[:host] + host ||= config.asset_host if defined? config.asset_host + + if host + if host.respond_to?(:call) + arity = host.respond_to?(:arity) ? host.arity : host.method(:call).arity + args = [source] + args << request if request && (arity > 1 || arity < 0) + host = host.call(*args) + elsif host.include?("%d") + host = host % (Zlib.crc32(source) % 4) + end + end + + host ||= request.base_url if request && options[:protocol] == :request + return unless host + + if URI_REGEXP.match?(host) + host + else + protocol = options[:protocol] || config.default_asset_host_protocol || (request ? :request : :relative) + case protocol + when :relative + "//#{host}" + when :request + "#{request.protocol}#{host}" + else + "#{protocol}://#{host}" + end + end + end + + # Computes the path to a JavaScript asset in the public javascripts directory. + # If the +source+ filename has no extension, .js will be appended (except for explicit URIs) + # Full paths from the document root will be passed through. + # Used internally by +javascript_include_tag+ to build the script path. + # + # javascript_path "xmlhr" # => /assets/xmlhr.js + # javascript_path "dir/xmlhr.js" # => /assets/dir/xmlhr.js + # javascript_path "/dir/xmlhr" # => /dir/xmlhr.js + # javascript_path "http://www.example.com/js/xmlhr" # => http://www.example.com/js/xmlhr + # javascript_path "http://www.example.com/js/xmlhr.js" # => http://www.example.com/js/xmlhr.js + def javascript_path(source, options = {}) + path_to_asset(source, { type: :javascript }.merge!(options)) + end + alias_method :path_to_javascript, :javascript_path # aliased to avoid conflicts with a javascript_path named route + + # Computes the full URL to a JavaScript asset in the public javascripts directory. + # This will use +javascript_path+ internally, so most of their behaviors will be the same. + # Since +javascript_url+ is based on +asset_url+ method you can set :host options. If :host + # options is set, it overwrites global +config.action_controller.asset_host+ setting. + # + # javascript_url "js/xmlhr.js", host: "http://stage.example.com" # => http://stage.example.com/assets/js/xmlhr.js + # + def javascript_url(source, options = {}) + url_to_asset(source, { type: :javascript }.merge!(options)) + end + alias_method :url_to_javascript, :javascript_url # aliased to avoid conflicts with a javascript_url named route + + # Computes the path to a stylesheet asset in the public stylesheets directory. + # If the +source+ filename has no extension, .css will be appended (except for explicit URIs). + # Full paths from the document root will be passed through. + # Used internally by +stylesheet_link_tag+ to build the stylesheet path. + # + # stylesheet_path "style" # => /assets/style.css + # stylesheet_path "dir/style.css" # => /assets/dir/style.css + # stylesheet_path "/dir/style.css" # => /dir/style.css + # stylesheet_path "http://www.example.com/css/style" # => http://www.example.com/css/style + # stylesheet_path "http://www.example.com/css/style.css" # => http://www.example.com/css/style.css + def stylesheet_path(source, options = {}) + path_to_asset(source, { type: :stylesheet }.merge!(options)) + end + alias_method :path_to_stylesheet, :stylesheet_path # aliased to avoid conflicts with a stylesheet_path named route + + # Computes the full URL to a stylesheet asset in the public stylesheets directory. + # This will use +stylesheet_path+ internally, so most of their behaviors will be the same. + # Since +stylesheet_url+ is based on +asset_url+ method you can set :host options. If :host + # options is set, it overwrites global +config.action_controller.asset_host+ setting. + # + # stylesheet_url "css/style.css", host: "http://stage.example.com" # => http://stage.example.com/assets/css/style.css + # + def stylesheet_url(source, options = {}) + url_to_asset(source, { type: :stylesheet }.merge!(options)) + end + alias_method :url_to_stylesheet, :stylesheet_url # aliased to avoid conflicts with a stylesheet_url named route + + # Computes the path to an image asset. + # Full paths from the document root will be passed through. + # Used internally by +image_tag+ to build the image path: + # + # image_path("edit") # => "/assets/edit" + # image_path("edit.png") # => "/assets/edit.png" + # image_path("icons/edit.png") # => "/assets/icons/edit.png" + # image_path("/icons/edit.png") # => "/icons/edit.png" + # image_path("http://www.example.com/img/edit.png") # => "http://www.example.com/img/edit.png" + # + # If you have images as application resources this method may conflict with their named routes. + # The alias +path_to_image+ is provided to avoid that. Rails uses the alias internally, and + # plugin authors are encouraged to do so. + def image_path(source, options = {}) + path_to_asset(source, { type: :image }.merge!(options)) + end + alias_method :path_to_image, :image_path # aliased to avoid conflicts with an image_path named route + + # Computes the full URL to an image asset. + # This will use +image_path+ internally, so most of their behaviors will be the same. + # Since +image_url+ is based on +asset_url+ method you can set :host options. If :host + # options is set, it overwrites global +config.action_controller.asset_host+ setting. + # + # image_url "edit.png", host: "http://stage.example.com" # => http://stage.example.com/assets/edit.png + # + def image_url(source, options = {}) + url_to_asset(source, { type: :image }.merge!(options)) + end + alias_method :url_to_image, :image_url # aliased to avoid conflicts with an image_url named route + + # Computes the path to a video asset in the public videos directory. + # Full paths from the document root will be passed through. + # Used internally by +video_tag+ to build the video path. + # + # video_path("hd") # => /videos/hd + # video_path("hd.avi") # => /videos/hd.avi + # video_path("trailers/hd.avi") # => /videos/trailers/hd.avi + # video_path("/trailers/hd.avi") # => /trailers/hd.avi + # video_path("http://www.example.com/vid/hd.avi") # => http://www.example.com/vid/hd.avi + def video_path(source, options = {}) + path_to_asset(source, { type: :video }.merge!(options)) + end + alias_method :path_to_video, :video_path # aliased to avoid conflicts with a video_path named route + + # Computes the full URL to a video asset in the public videos directory. + # This will use +video_path+ internally, so most of their behaviors will be the same. + # Since +video_url+ is based on +asset_url+ method you can set :host options. If :host + # options is set, it overwrites global +config.action_controller.asset_host+ setting. + # + # video_url "hd.avi", host: "http://stage.example.com" # => http://stage.example.com/videos/hd.avi + # + def video_url(source, options = {}) + url_to_asset(source, { type: :video }.merge!(options)) + end + alias_method :url_to_video, :video_url # aliased to avoid conflicts with a video_url named route + + # Computes the path to an audio asset in the public audios directory. + # Full paths from the document root will be passed through. + # Used internally by +audio_tag+ to build the audio path. + # + # audio_path("horse") # => /audios/horse + # audio_path("horse.wav") # => /audios/horse.wav + # audio_path("sounds/horse.wav") # => /audios/sounds/horse.wav + # audio_path("/sounds/horse.wav") # => /sounds/horse.wav + # audio_path("http://www.example.com/sounds/horse.wav") # => http://www.example.com/sounds/horse.wav + def audio_path(source, options = {}) + path_to_asset(source, { type: :audio }.merge!(options)) + end + alias_method :path_to_audio, :audio_path # aliased to avoid conflicts with an audio_path named route + + # Computes the full URL to an audio asset in the public audios directory. + # This will use +audio_path+ internally, so most of their behaviors will be the same. + # Since +audio_url+ is based on +asset_url+ method you can set :host options. If :host + # options is set, it overwrites global +config.action_controller.asset_host+ setting. + # + # audio_url "horse.wav", host: "http://stage.example.com" # => http://stage.example.com/audios/horse.wav + # + def audio_url(source, options = {}) + url_to_asset(source, { type: :audio }.merge!(options)) + end + alias_method :url_to_audio, :audio_url # aliased to avoid conflicts with an audio_url named route + + # Computes the path to a font asset. + # Full paths from the document root will be passed through. + # + # font_path("font") # => /fonts/font + # font_path("font.ttf") # => /fonts/font.ttf + # font_path("dir/font.ttf") # => /fonts/dir/font.ttf + # font_path("/dir/font.ttf") # => /dir/font.ttf + # font_path("http://www.example.com/dir/font.ttf") # => http://www.example.com/dir/font.ttf + def font_path(source, options = {}) + path_to_asset(source, { type: :font }.merge!(options)) + end + alias_method :path_to_font, :font_path # aliased to avoid conflicts with a font_path named route + + # Computes the full URL to a font asset. + # This will use +font_path+ internally, so most of their behaviors will be the same. + # Since +font_url+ is based on +asset_url+ method you can set :host options. If :host + # options is set, it overwrites global +config.action_controller.asset_host+ setting. + # + # font_url "font.ttf", host: "http://stage.example.com" # => http://stage.example.com/fonts/font.ttf + # + def font_url(source, options = {}) + url_to_asset(source, { type: :font }.merge!(options)) + end + alias_method :url_to_font, :font_url # aliased to avoid conflicts with a font_url named route + end + end +end |