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Diffstat (limited to 'guides/source/asset_pipeline.md')
| -rw-r--r-- | guides/source/asset_pipeline.md | 59 |
1 files changed, 31 insertions, 28 deletions
diff --git a/guides/source/asset_pipeline.md b/guides/source/asset_pipeline.md index e6631a513c..25717e04e4 100644 --- a/guides/source/asset_pipeline.md +++ b/guides/source/asset_pipeline.md @@ -485,7 +485,7 @@ which contains these lines: Rails creates both `app/assets/javascripts/application.js` and `app/assets/stylesheets/application.css` regardless of whether the ---skip-sprockets option is used when creating a new rails application. This is +--skip-sprockets option is used when creating a new Rails application. This is so you can easily add asset pipelining later if you like. The directives that work in JavaScript files also work in stylesheets @@ -586,6 +586,19 @@ in your application are included in the `config.assets.precompile` list. If `config.assets.digest` is also true, the asset pipeline will require that all requests for assets include digests. +### Raise an Error When an Asset is Not Found + +If you are using sprockets-rails >= 3.2.0 you can configure what happens +when an asset lookup is performed and nothing is found. If you turn off "asset fallback" +then an error will be raised when an asset cannot be found. + +```ruby +config.assets.unknown_asset_fallback = false +``` + +If "asset fallback" is enabled then when an asset cannot be found the path will be +output instead and no error raised. The asset fallback behavior is enabled by default. + ### Turning Digests Off You can turn off digests by updating `config/environments/development.rb` to @@ -724,7 +737,7 @@ If you have other manifests or individual stylesheets and JavaScript files to include, you can add them to the `precompile` array in `config/initializers/assets.rb`: ```ruby -Rails.application.config.assets.precompile += ['admin.js', 'admin.css', 'swfObject.js'] +Rails.application.config.assets.precompile += %w( admin.js admin.css ) ``` NOTE. Always specify an expected compiled filename that ends with .js or .css, @@ -1024,7 +1037,7 @@ to tell our CDN (and browser) that the asset is "public", that means any cache can store the request. Also we commonly want to set `max-age` which is how long the cache will store the object before invalidating the cache. The `max-age` value is set to seconds with a maximum possible value of `31536000` which is one -year. You can do this in your rails application by setting +year. You can do this in your Rails application by setting ``` config.public_file_server.headers = { @@ -1109,9 +1122,9 @@ Windows you have a JavaScript runtime installed in your operating system. ### Serving GZipped version of assets -By default, gzipped version of compiled assets will be generated, along -with the non-gzipped version of assets. Gzipped assets help reduce the transmission of -data over the wire. You can configure this by setting the `gzip` flag. +By default, gzipped version of compiled assets will be generated, along with +the non-gzipped version of assets. Gzipped assets help reduce the transmission +of data over the wire. You can configure this by setting the `gzip` flag. ```ruby config.assets.gzip = false # disable gzipped assets generation @@ -1214,35 +1227,25 @@ Sprockets. Making Your Library or Gem a Pre-Processor ------------------------------------------ -As Sprockets uses [Tilt](https://github.com/rtomayko/tilt) as a generic -interface to different templating engines, your gem should just implement the -Tilt template protocol. Normally, you would subclass `Tilt::Template` and -reimplement the `prepare` method, which initializes your template, and the -`evaluate` method, which returns the processed source. The original source is -stored in `data`. Have a look at -[`Tilt::Template`](https://github.com/rtomayko/tilt/blob/master/lib/tilt/template.rb) -sources to learn more. +Sprockets uses Processors, Transformers, Compressors, and Exporters to extend +Sprockets functionality. Have a look at +[Extending Sprockets](https://github.com/rails/sprockets/blob/master/guides/extending_sprockets.md) +to learn more. Here we registered a preprocessor to add a comment to the end +of text/css (.css) files. ```ruby -module BangBang - class Template < ::Tilt::Template - def prepare - # Do any initialization here - end - - # Adds a "!" to original template. - def evaluate(scope, locals, &block) - "#{data}!" - end +module AddComment + def self.call(input) + { data: input[:data] + "/* Hello From my sprockets extension */" } end end ``` -Now that you have a `Template` class, it's time to associate it with an -extension for template files: +Now that you have a module that modifies the input data, it's time to register +it as a preprocessor for your mime type. ```ruby -Sprockets.register_engine '.bang', BangBang::Template +Sprockets.register_preprocessor 'text/css', AddComment ``` Upgrading from Old Versions of Rails @@ -1291,7 +1294,7 @@ config.assets.digest = true # Precompile additional assets (application.js, application.css, and all # non-JS/CSS are already added) -# config.assets.precompile += %w( search.js ) +# config.assets.precompile += %w( admin.js admin.css ) ``` Rails 4 and above no longer set default config values for Sprockets in `test.rb`, so |