Module: Webpacker::Helper

Defined in:
lib/webpacker/helper.rb

Instance Method Summary collapse

Instance Method Details

#asset_pack_path(name, **options) ⇒ Object

Computes the relative path for a given Webpacker asset. Returns the relative path using manifest.json and passes it to path_to_asset helper. This will use path_to_asset internally, so most of their behaviors will be the same.

Example:

<%= asset_pack_path 'calendar.css' %> # => "/packs/calendar-1016838bab065ae1e122.css"

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# File 'lib/webpacker/helper.rb', line 16

def asset_pack_path(name, **options)
  path_to_asset(current_webpacker_instance.manifest.lookup!(name), options)
end

#asset_pack_url(name, **options) ⇒ Object

Computes the absolute path for a given Webpacker asset. Returns the absolute path using manifest.json and passes it to url_to_asset helper. This will use url_to_asset internally, so most of their behaviors will be the same.

Example:

<%= asset_pack_url 'calendar.css' %> # => "http://example.com/packs/calendar-1016838bab065ae1e122.css"

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# File 'lib/webpacker/helper.rb', line 27

def asset_pack_url(name, **options)
  url_to_asset(current_webpacker_instance.manifest.lookup!(name), options)
end

#current_webpacker_instanceObject

Returns the current Webpacker instance. Could be overridden to use multiple Webpacker configurations within the same app (e.g. with engines).


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# File 'lib/webpacker/helper.rb', line 5

def current_webpacker_instance
  Webpacker.instance
end

#favicon_pack_tag(name, **options) ⇒ Object

Creates a link tag for a favicon that references the named pack file.

Example:

<%= favicon_pack_tag 'mb-icon.png', rel: 'apple-touch-icon', type: 'image/png' %>
<link href="/packs/mb-icon-k344a6d59eef8632c9d1.png" rel="apple-touch-icon" type="image/png" />

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# File 'lib/webpacker/helper.rb', line 71

def favicon_pack_tag(name, **options)
  favicon_link_tag(resolve_path_to_image(name), options)
end

#image_pack_path(name, **options) ⇒ Object

Computes the relative path for a given Webpacker image with the same automated processing as image_pack_tag. Returns the relative path using manifest.json and passes it to path_to_asset helper. This will use path_to_asset internally, so most of their behaviors will be the same.


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# File 'lib/webpacker/helper.rb', line 34

def image_pack_path(name, **options)
  resolve_path_to_image(name, **options)
end

#image_pack_tag(name, **options) ⇒ Object

Creates an image tag that references the named pack file.

Example:

<%= image_pack_tag 'application.png', size: '16x10', alt: 'Edit Entry' %>
<img alt='Edit Entry' src='/packs/application-k344a6d59eef8632c9d1.png' width='16' height='10' />

<%= image_pack_tag 'picture.png', srcset: { 'picture-2x.png' => '2x' } %>
<img srcset= "/packs/picture-2x-7cca48e6cae66ec07b8e.png 2x" src="/packs/picture-c38deda30895059837cf.png" >

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# File 'lib/webpacker/helper.rb', line 55

def image_pack_tag(name, **options)
  if options[:srcset] && !options[:srcset].is_a?(String)
    options[:srcset] = options[:srcset].map do |src_name, size|
      "#{resolve_path_to_image(src_name)} #{size}"
    end.join(", ")
  end

  image_tag(resolve_path_to_image(name), options)
end

#image_pack_url(name, **options) ⇒ Object

Computes the absolute path for a given Webpacker image with the same automated processing as image_pack_tag. Returns the relative path using manifest.json and passes it to path_to_asset helper. This will use path_to_asset internally, so most of their behaviors will be the same.


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# File 'lib/webpacker/helper.rb', line 42

def image_pack_url(name, **options)
  resolve_path_to_image(name, **options.merge(protocol: :request))
end

#javascript_pack_tag(*names, defer: true, **options) ⇒ Object

Creates script tags that reference the js chunks from entrypoints when using split chunks API, as compiled by webpack per the entries list in package/environments/base.js. By default, this list is auto-generated to match everything in app/packs/entrypoints/*.js and all the dependent chunks. In production mode, the digested reference is automatically looked up. See: webpack.js.org/plugins/split-chunks-plugin/

Example:

<%= javascript_pack_tag 'calendar', 'map', 'data-turbolinks-track': 'reload' %> # =>
<script src="/packs/vendor-16838bab065ae1e314.chunk.js" data-turbolinks-track="reload" defer="true"></script>
<script src="/packs/calendar~runtime-16838bab065ae1e314.chunk.js" data-turbolinks-track="reload" defer="true"></script>
<script src="/packs/calendar-1016838bab065ae1e314.chunk.js" data-turbolinks-track="reload" defer="true"></script>
<script src="/packs/map~runtime-16838bab065ae1e314.chunk.js" data-turbolinks-track="reload" defer="true"></script>
<script src="/packs/map-16838bab065ae1e314.chunk.js" data-turbolinks-track="reload" defer="true"></script>

DO:

<%= javascript_pack_tag 'calendar', 'map' %>

DON'T:

<%= javascript_pack_tag 'calendar' %>
<%= javascript_pack_tag 'map' %>

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# File 'lib/webpacker/helper.rb', line 98

def javascript_pack_tag(*names, defer: true, **options)
  javascript_include_tag(*sources_from_manifest_entrypoints(names, type: :javascript), **options.tap { |o| o[:defer] = defer })
end

#preload_pack_asset(name, **options) ⇒ Object

Creates a link tag, for preloading, that references a given Webpacker asset. In production mode, the digested reference is automatically looked up. See: developer.mozilla.org/en-US/docs/Web/HTML/Preloading_content

Example:

<%= preload_pack_asset 'fonts/fa-regular-400.woff2' %> # =>
<link rel="preload" href="/packs/fonts/fa-regular-400-944fb546bd7018b07190a32244f67dc9.woff2" as="font" type="font/woff2" crossorigin="anonymous">

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# File 'lib/webpacker/helper.rb', line 110

def preload_pack_asset(name, **options)
  if self.class.method_defined?(:preload_link_tag)
    preload_link_tag(current_webpacker_instance.manifest.lookup!(name), options)
  else
    raise "You need Rails >= 5.2 to use this tag."
  end
end

#stylesheet_pack_tag(*names, **options) ⇒ Object

Creates link tags that reference the css chunks from entrypoints when using split chunks API, as compiled by webpack per the entries list in package/environments/base.js. By default, this list is auto-generated to match everything in app/packs/entrypoints/*.js and all the dependent chunks. In production mode, the digested reference is automatically looked up. See: webpack.js.org/plugins/split-chunks-plugin/

Examples:

<%= stylesheet_pack_tag 'calendar', 'map' %> # =>
<link rel="stylesheet" media="screen" href="/packs/3-8c7ce31a.chunk.css" />
<link rel="stylesheet" media="screen" href="/packs/calendar-8c7ce31a.chunk.css" />
<link rel="stylesheet" media="screen" href="/packs/map-8c7ce31a.chunk.css" />

When using the webpack-dev-server, CSS is inlined so HMR can be turned on for CSS,
including CSS modules
<%= stylesheet_pack_tag 'calendar', 'map' %> # => nil

DO:

<%= stylesheet_pack_tag 'calendar', 'map' %>

DON'T:

<%= stylesheet_pack_tag 'calendar' %>
<%= stylesheet_pack_tag 'map' %>

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# File 'lib/webpacker/helper.rb', line 143

def stylesheet_pack_tag(*names, **options)
  return "" if Webpacker.inlining_css?

  stylesheet_link_tag(*sources_from_manifest_entrypoints(names, type: :stylesheet), **options)
end