# frozen_string_literal: true
require "active_support/core_ext/array/extract_options"
require "active_support/core_ext/hash/keys"
require "action_view/helpers/asset_url_helper"
require "action_view/helpers/tag_helper"
module ActionView
# = Action View Asset Tag Helpers
module Helpers #:nodoc:
# This module provides methods for generating HTML that links views to assets such
# as images, JavaScripts, stylesheets, and feeds. These methods do not verify
# the assets exist before linking to them:
#
# image_tag("rails.png")
# # => <img src="/assets/rails.png" />
# stylesheet_link_tag("application")
# # => <link href="/assets/application.css?body=1" media="screen" rel="stylesheet" />
module AssetTagHelper
extend ActiveSupport::Concern
include AssetUrlHelper
include TagHelper
# Returns an HTML script tag for each of the +sources+ provided.
#
# Sources may be paths to JavaScript files. Relative paths are assumed to be relative
# to <tt>assets/javascripts</tt>, full paths are assumed to be relative to the document
# root. Relative paths are idiomatic, use absolute paths only when needed.
#
# When passing paths, the ".js" extension is optional. If you do not want ".js"
# appended to the path <tt>extname: false</tt> can be set on the options.
#
# You can modify the HTML attributes of the script tag by passing a hash as the
# last argument.
#
# When the Asset Pipeline is enabled, you can pass the name of your manifest as
# source, and include other JavaScript or CoffeeScript files inside the manifest.
#
# If the server supports Early Hints header links for these assets will be
# automatically pushed.
#
# ==== Options
#
# When the last parameter is a hash you can add HTML attributes using that
# parameter. The following options are supported:
#
# * <tt>:extname</tt> - Append an extension to the generated url unless the extension
# already exists. This only applies for relative urls.
# * <tt>:protocol</tt> - Sets the protocol of the generated url, this option only
# applies when a relative url and +host+ options are provided.
# * <tt>:host</tt> - When a relative url is provided the host is added to the
# that path.
# * <tt>:skip_pipeline</tt> - This option is used to bypass the asset pipeline
# when it is set to true.
#
# ==== Examples
#
# javascript_include_tag "xmlhr"
# # => <script src="/assets/xmlhr.debug-1284139606.js"></script>
#
# javascript_include_tag "xmlhr", host: "localhost", protocol: "https"
# # => <script src="https://localhost/assets/xmlhr.debug-1284139606.js"></script>
#
# javascript_include_tag "template.jst", extname: false
# # => <script src="/assets/template.debug-1284139606.jst"></script>
#
# javascript_include_tag "xmlhr.js"
# # => <script src="/assets/xmlhr.debug-1284139606.js"></script>
#
# javascript_include_tag "common.javascript", "/elsewhere/cools"
# # => <script src="/assets/common.javascript.debug-1284139606.js"></script>
# # <script src="/elsewhere/cools.debug-1284139606.js"></script>
#
# javascript_include_tag "http://www.example.com/xmlhr"
# # => <script src="http://www.example.com/xmlhr"></script>
#
# javascript_include_tag "http://www.example.com/xmlhr.js"
# # => <script src="http://www.example.com/xmlhr.js"></script>
def javascript_include_tag(*sources)
options = sources.extract_options!.stringify_keys
path_options = options.extract!("protocol", "extname", "host", "skip_pipeline").symbolize_keys
early_hints_links = []
sources_tags = sources.uniq.map { |source|
href = path_to_javascript(source, path_options)
early_hints_links << "<#{href}>; rel=preload; as=script"
tag_options = {
"src" => href
}.merge!(options)
content_tag("script".freeze, "", tag_options)
}.join("\n").html_safe
request.send_early_hints("Link" => early_hints_links.join("\n")) if respond_to?(:request)
sources_tags
end
# Returns a stylesheet link tag for the sources specified as arguments. If
# you don't specify an extension, <tt>.css</tt> will be appended automatically.
# You can modify the link attributes by passing a hash as the last argument.
# For historical reasons, the 'media' attribute will always be present and defaults
# to "screen", so you must explicitly set it to "all" for the stylesheet(s) to
# apply to all media types.
#
# If the server supports Early Hints header links for these assets will be
# automatically pushed.
#
# stylesheet_link_tag "style"
# # => <link href="/assets/style.css" media="screen" rel="stylesheet" />
#
# stylesheet_link_tag "style.css"
# # => <link href="/assets/style.css" media="screen" rel="stylesheet" />
#
# stylesheet_link_tag "http://www.example.com/style.css"
# # => <link href="http://www.example.com/style.css" media="screen" rel="stylesheet" />
#
# stylesheet_link_tag "style", media: "all"
# # => <link href="/assets/style.css" media="all" rel="stylesheet" />
#
# stylesheet_link_tag "style", media: "print"
# # => <link href="/assets/style.css" media="print" rel="stylesheet" />
#
# stylesheet_link_tag "random.styles", "/css/stylish"
# # => <link href="/assets/random.styles" media="screen" rel="stylesheet" />
# # <link href="/css/stylish.css" media="screen" rel="stylesheet" />
def stylesheet_link_tag(*sources)
options = sources.extract_options!.stringify_keys
path_options = options.extract!("protocol", "host", "skip_pipeline").symbolize_keys
early_hints_links = []
sources_tags = sources.uniq.map { |source|
href = path_to_stylesheet(source, path_options)
early_hints_links << "<#{href}>; rel=preload; as=stylesheet"
tag_options = {
"rel" => "stylesheet",
"media" => "screen",
"href" => href
}.merge!(options)
tag(:link, tag_options)
}.join("\n").html_safe
request.send_early_hints("Link" => early_hints_links.join("\n")) if respond_to?(:request)
sources_tags
end
# Returns a link tag that browsers and feed readers can use to auto-detect
# an RSS, Atom, or JSON feed. The +type+ can be <tt>:rss</tt> (default),
# <tt>:atom</tt>, or <tt>:json</tt>. Control the link options in url_for format
# using the +url_options+. You can modify the LINK tag itself in +tag_options+.
#
# ==== Options
#
# * <tt>:rel</tt> - Specify the relation of this link, defaults to "alternate"
# * <tt>:type</tt> - Override the auto-generated mime type
# * <tt>:title</tt> - Specify the title of the link, defaults to the +type+
#
# ==== Examples
#
# auto_discovery_link_tag
# # => <link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.currenthost.com/controller/action" />
# auto_discovery_link_tag(:atom)
# # => <link rel="alternate" type="application/atom+xml" title="ATOM" href="http://www.currenthost.com/controller/action" />
# auto_discovery_link_tag(:json)
# # => <link rel="alternate" type="application/json" title="JSON" href="http://www.currenthost.com/controller/action" />
# auto_discovery_link_tag(:rss, {action: "feed"})
# # => <link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.currenthost.com/controller/feed" />
# auto_discovery_link_tag(:rss, {action: "feed"}, {title: "My RSS"})
# # => <link rel="alternate" type="application/rss+xml" title="My RSS" href="http://www.currenthost.com/controller/feed" />
# auto_discovery_link_tag(:rss, {controller: "news", action: "feed"})
# # => <link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.currenthost.com/news/feed" />
# auto_discovery_link_tag(:rss, "http://www.example.com/feed.rss", {title: "Example RSS"})
# # => <link rel="alternate" type="application/rss+xml" title="Example RSS" href="http://www.example.com/feed.rss" />
def auto_discovery_link_tag(type = :rss, url_options = {}, tag_options = {})
if !(type == :rss || type == :atom || type == :json) && tag_options[:type].blank?
raise ArgumentError.new("You should pass :type tag_option key explicitly, because you have passed #{type} type other than :rss, :atom, or :json.")
end
tag(
"link",
"rel" => tag_options[:rel] || "alternate",
"type" => tag_options[:type] || Template::Types[type].to_s,
"title" => tag_options[:title] || type.to_s.upcase,
"href" => url_options.is_a?(Hash) ? url_for(url_options.merge(only_path: false)) : url_options
)
end
# Returns a link tag for a favicon managed by the asset pipeline.
#
# If a page has no link like the one generated by this helper, browsers
# ask for <tt>/favicon.ico</tt> automatically, and cache the file if the
# request succeeds. If the favicon changes it is hard to get it updated.
#
# To have better control applications may let the asset pipeline manage
# their favicon storing the file under <tt>app/assets/images</tt>, and
# using this helper to generate its corresponding link tag.
#
# The helper gets the name of the favicon file as first argument, which
# defaults to "favicon.ico", and also supports +:rel+ and +:type+ options
# to override their defaults, "shortcut icon" and "image/x-icon"
# respectively:
#
# favicon_link_tag
# # => <link href="/assets/favicon.ico" rel="shortcut icon" type="image/x-icon" />
#
# favicon_link_tag 'myicon.ico'
# # => <link href="/assets/myicon.ico" rel="shortcut icon" type="image/x-icon" />
#
# Mobile Safari looks for a different link tag, pointing to an image that
# will be used if you add the page to the home screen of an iOS device.
# The following call would generate such a tag:
#
# favicon_link_tag 'mb-icon.png', rel: 'apple-touch-icon', type: 'image/png'
# # => <link href="/assets/mb-icon.png" rel="apple-touch-icon" type="image/png" />
def favicon_link_tag(source = "favicon.ico", options = {})
tag("link", {
rel: "shortcut icon",
type: "image/x-icon",
href: path_to_image(source, skip_pipeline: options.delete(:skip_pipeline))
}.merge!(options.symbolize_keys))
end
# Returns an HTML image tag for the +source+. The +source+ can be a full
# path, a file or an Active Storage attachment.
#
# ==== Options
#
# You can add HTML attributes using the +options+. The +options+ supports
# additional keys for convenience and conformance:
#
# * <tt>:size</tt> - Supplied as "{Width}x{Height}" or "{Number}", so "30x45" becomes
# width="30" and height="45", and "50" becomes width="50" and height="50".
# <tt>:size</tt> will be ignored if the value is not in the correct format.
# * <tt>:srcset</tt> - If supplied as a hash or array of <tt>[source, descriptor]</tt>
# pairs, each image path will be expanded before the list is formatted as a string.
#
# ==== Examples
#
# Assets (images that are part of your app):
#
# image_tag("icon")
# # => <img src="/assets/icon" />
# image_tag("icon.png")
# # => <img src="/assets/icon.png" />
# image_tag("icon.png", size: "16x10", alt: "Edit Entry")
# # => <img src="/assets/icon.png" width="16" height="10" alt="Edit Entry" />
# image_tag("/icons/icon.gif", size: "16")
# # => <img src="/icons/icon.gif" width="16" height="16" />
# image_tag("/icons/icon.gif", height: '32', width: '32')
# # => <img height="32" src="/icons/icon.gif" width="32" />
# image_tag("/icons/icon.gif", class: "menu_icon")
# # => <img class="menu_icon" src="/icons/icon.gif" />
# image_tag("/icons/icon.gif", data: { title: 'Rails Application' })
# # => <img data-title="Rails Application" src="/icons/icon.gif" />
# image_tag("icon.png", srcset: { "icon_2x.png" => "2x", "icon_4x.png" => "4x" })
# # => <img src="/assets/icon.png" srcset="/assets/icon_2x.png 2x, /assets/icon_4x.png 4x">
# image_tag("pic.jpg", srcset: [["pic_1024.jpg", "1024w"], ["pic_1980.jpg", "1980w"]], sizes: "100vw")
# # => <img src="/assets/pic.jpg" srcset="/assets/pic_1024.jpg 1024w, /assets/pic_1980.jpg 1980w" sizes="100vw">
#
# Active Storage (images that are uploaded by the users of your app):
#
# image_tag(user.avatar)
# # => <img src="/rails/active_storage/blobs/.../tiger.jpg" />
# image_tag(user.avatar.variant(resize: "100x100"))
# # => <img src="/rails/active_storage/variants/.../tiger.jpg" />
# image_tag(user.avatar.variant(resize: "100x100"), size: '100')
# # => <img width="100" height="100" src="/rails/active_storage/variants/.../tiger.jpg" />
def image_tag(source, options = {})
options = options.symbolize_keys
check_for_image_tag_errors(options)
skip_pipeline = options.delete(:skip_pipeline)
options[:src] = resolve_image_source(source, skip_pipeline)
if options[:srcset] && !options[:srcset].is_a?(String)
options[:srcset] = options[:srcset].map do |src_path, size|
src_path = path_to_image(src_path, skip_pipeline: skip_pipeline)
"#{src_path} #{size}"
end.join(", ")
end
options[:width], options[:height] = extract_dimensions(options.delete(:size)) if options[:size]
tag("img", options)
end
# Returns a string suitable for an HTML image tag alt attribute.
# The +src+ argument is meant to be an image file path.
# The method removes the basename of the file path and the digest,
# if any. It also removes hyphens and underscores from file names and
# replaces them with spaces, returning a space-separated, titleized
# string.
#
# ==== Examples
#
# image_alt('rails.png')
# # => Rails
#
# image_alt('hyphenated-file-name.png')
# # => Hyphenated file name
#
# image_alt('underscored_file_name.png')
# # => Underscored file name
def image_alt(src)
ActiveSupport::Deprecation.warn("image_alt is deprecated and will be removed from Rails 6.0. You must explicitly set alt text on images.")
File.basename(src, ".*".freeze).sub(/-[[:xdigit:]]{32,64}\z/, "".freeze).tr("-_".freeze, " ".freeze).capitalize
end
# Returns an HTML video tag for the +sources+. If +sources+ is a string,
# a single video tag will be returned. If +sources+ is an array, a video
# tag with nested source tags for each source will be returned. The
# +sources+ can be full paths or files that exists in your public videos
# directory.
#
# ==== Options
# You can add HTML attributes using the +options+. The +options+ supports
# two additional keys for convenience and conformance:
#
# * <tt>:poster</tt> - Set an image (like a screenshot) to be shown
# before the video loads. The path is calculated like the +src+ of +image_tag+.
# * <tt>:size</tt> - Supplied as "{Width}x{Height}" or "{Number}", so "30x45" becomes
# width="30" and height="45", and "50" becomes width="50" and height="50".
# <tt>:size</tt> will be ignored if the value is not in the correct format.
# * <tt>:poster_skip_pipeline</tt> will bypass the asset pipeline when using
# the <tt>:poster</tt> option instead using an asset in the public folder.
#
# ==== Examples
#
# video_tag("trailer")
# # => <video src="/videos/trailer"></video>
# video_tag("trailer.ogg")
# # => <video src="/videos/trailer.ogg"></video>
# video_tag("trailer.ogg", controls: true, preload: 'none')
# # => <video preload="none" controls="controls" src="/videos/trailer.ogg" ></video>
# video_tag("trailer.m4v", size: "16x10", poster: "screenshot.png")
# # => <video src="/videos/trailer.m4v" width="16" height="10" poster="/assets/screenshot.png"></video>
# video_tag("trailer.m4v", size: "16x10", poster: "screenshot.png", poster_skip_pipeline: true)
# # => <video src="/videos/trailer.m4v" width="16" height="10" poster="screenshot.png"></video>
# video_tag("/trailers/hd.avi", size: "16x16")
# # => <video src="/trailers/hd.avi" width="16" height="16"></video>
# video_tag("/trailers/hd.avi", size: "16")
# # => <video height="16" src="/trailers/hd.avi" width="16"></video>
# video_tag("/trailers/hd.avi", height: '32', width: '32')
# # => <video height="32" src="/trailers/hd.avi" width="32"></video>
# video_tag("trailer.ogg", "trailer.flv")
# # => <video><source src="/videos/trailer.ogg" /><source src="/videos/trailer.flv" /></video>
# video_tag(["trailer.ogg", "trailer.flv"])
# # => <video><source src="/videos/trailer.ogg" /><source src="/videos/trailer.flv" /></video>
# video_tag(["trailer.ogg", "trailer.flv"], size: "160x120")
# # => <video height="120" width="160"><source src="/videos/trailer.ogg" /><source src="/videos/trailer.flv" /></video>
def video_tag(*sources)
options = sources.extract_options!.symbolize_keys
public_poster_folder = options.delete(:poster_skip_pipeline)
sources << options
multiple_sources_tag_builder("video", sources) do |tag_options|
tag_options[:poster] = path_to_image(tag_options[:poster], skip_pipeline: public_poster_folder) if tag_options[:poster]
tag_options[:width], tag_options[:height] = extract_dimensions(tag_options.delete(:size)) if tag_options[:size]
end
end
# Returns an HTML audio tag for the +source+.
# The +source+ can be full path or file that exists in
# your public audios directory.
#
# audio_tag("sound")
# # => <audio src="/audios/sound"></audio>
# audio_tag("sound.wav")
# # => <audio src="/audios/sound.wav"></audio>
# audio_tag("sound.wav", autoplay: true, controls: true)
# # => <audio autoplay="autoplay" controls="controls" src="/audios/sound.wav"></audio>
# audio_tag("sound.wav", "sound.mid")
# # => <audio><source src="/audios/sound.wav" /><source src="/audios/sound.mid" /></audio>
def audio_tag(*sources)
multiple_sources_tag_builder("audio", sources)
end
private
def multiple_sources_tag_builder(type, sources)
options = sources.extract_options!.symbolize_keys
skip_pipeline = options.delete(:skip_pipeline)
sources.flatten!
yield options if block_given?
if sources.size > 1
content_tag(type, options) do
safe_join sources.map { |source| tag("source", src: send("path_to_#{type}", source, skip_pipeline: skip_pipeline)) }
end
else
options[:src] = send("path_to_#{type}", sources.first, skip_pipeline: skip_pipeline)
content_tag(type, nil, options)
end
end
def resolve_image_source(source, skip_pipeline)
if source.is_a?(Symbol) || source.is_a?(String)
path_to_image(source, skip_pipeline: skip_pipeline)
else
polymorphic_url(source)
end
rescue NoMethodError => e
raise ArgumentError, "Can't resolve image into URL: #{e}"
end
def extract_dimensions(size)
size = size.to_s
if /\A\d+x\d+\z/.match?(size)
size.split("x")
elsif /\A\d+\z/.match?(size)
[size, size]
end
end
def check_for_image_tag_errors(options)
if options[:size] && (options[:height] || options[:width])
raise ArgumentError, "Cannot pass a :size option with a :height or :width option"
end
end
end
end
end