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diff --git a/guides/source/asset_pipeline.md b/guides/source/asset_pipeline.md index 41dfeea84d..68dde4482f 100644 --- a/guides/source/asset_pipeline.md +++ b/guides/source/asset_pipeline.md @@ -78,9 +78,9 @@ requests can mean faster loading for your application. Sprockets concatenates all JavaScript files into one master `.js` file and all CSS files into one master `.css` file. As you'll learn later in this guide, you can customize this strategy to group files any way you like. In production, -Rails inserts an MD5 fingerprint into each filename so that the file is cached -by the web browser. You can invalidate the cache by altering this fingerprint, -which happens automatically whenever you change the file contents. +Rails inserts an SHA256 fingerprint into each filename so that the file is +cached by the web browser. You can invalidate the cache by altering this +fingerprint, which happens automatically whenever you change the file contents. The second feature of the asset pipeline is asset minification or compression. For CSS files, this is done by removing whitespace and comments. For JavaScript, @@ -106,7 +106,7 @@ or in web browsers) to keep their own copy of the content. When the content is updated, the fingerprint will change. This will cause the remote clients to request a new copy of the content. This is generally known as _cache busting_. -The technique sprockets uses for fingerprinting is to insert a hash of the +The technique Sprockets uses for fingerprinting is to insert a hash of the content into the name, usually at the end. For example a CSS file `global.css` ``` @@ -207,7 +207,7 @@ default .coffee and .scss files will not be precompiled on their own. See precompiling works. NOTE: You must have an ExecJS supported runtime in order to use CoffeeScript. -If you are using Mac OS X or Windows, you have a JavaScript runtime installed in +If you are using macOS or Windows, you have a JavaScript runtime installed in your operating system. Check [ExecJS](https://github.com/rails/execjs#readme) documentation to know all supported JavaScript runtimes. You can also disable generation of controller specific asset files by adding the @@ -346,9 +346,9 @@ Provided that the pipeline is enabled within your application (and not disabled in the current environment context), this file is served by Sprockets. If a file exists at `public/assets/rails.png` it is served by the web server. -Alternatively, a request for a file with an MD5 hash such as -`public/assets/rails-af27b6a414e6da00003503148be9b409.png` is treated the same -way. How these hashes are generated is covered in the [In +Alternatively, a request for a file with an SHA256 hash such as +`public/assets/rails-f90d8a84c707a8dc923fca1ca1895ae8ed0a09237f6992015fef1e11be77c023.png` +is treated the same way. How these hashes are generated is covered in the [In Production](#in-production) section later on in this guide. Sprockets will also look through the paths specified in `config.assets.paths`, @@ -654,7 +654,7 @@ In the production environment Sprockets uses the fingerprinting scheme outlined above. By default Rails assumes assets have been precompiled and will be served as static assets by your web server. -During the precompilation phase an MD5 is generated from the contents of the +During the precompilation phase an SHA256 is generated from the contents of the compiled files, and inserted into the filenames as they are written to disk. These fingerprinted names are used by the Rails helpers in place of the manifest name. @@ -743,22 +743,24 @@ Rails.application.config.assets.precompile += %w( admin.js admin.css ) NOTE. Always specify an expected compiled filename that ends with .js or .css, even if you want to add Sass or CoffeeScript files to the precompile array. -The task also generates a `manifest-md5hash.json` that contains a list with -all your assets and their respective fingerprints. This is used by the Rails -helper methods to avoid handing the mapping requests back to Sprockets. A -typical manifest file looks like: +The task also generates a `.sprockets-manifest-md5hash.json` (where `md5hash` is +an MD5 hash) that contains a list with all your assets and their respective +fingerprints. This is used by the Rails helper methods to avoid handing the +mapping requests back to Sprockets. A typical manifest file looks like: ```ruby -{"files":{"application-723d1be6cc741a3aabb1cec24276d681.js":{"logical_path":"application.js","mtime":"2013-07-26T22:55:03-07:00","size":302506, -"digest":"723d1be6cc741a3aabb1cec24276d681"},"application-12b3c7dd74d2e9df37e7cbb1efa76a6d.css":{"logical_path":"application.css","mtime":"2013-07-26T22:54:54-07:00","size":1560, -"digest":"12b3c7dd74d2e9df37e7cbb1efa76a6d"},"application-1c5752789588ac18d7e1a50b1f0fd4c2.css":{"logical_path":"application.css","mtime":"2013-07-26T22:56:17-07:00","size":1591, -"digest":"1c5752789588ac18d7e1a50b1f0fd4c2"},"favicon-a9c641bf2b81f0476e876f7c5e375969.ico":{"logical_path":"favicon.ico","mtime":"2013-07-26T23:00:10-07:00","size":1406, -"digest":"a9c641bf2b81f0476e876f7c5e375969"},"my_image-231a680f23887d9dd70710ea5efd3c62.png":{"logical_path":"my_image.png","mtime":"2013-07-26T23:00:27-07:00","size":6646, -"digest":"231a680f23887d9dd70710ea5efd3c62"}},"assets":{"application.js": -"application-723d1be6cc741a3aabb1cec24276d681.js","application.css": -"application-1c5752789588ac18d7e1a50b1f0fd4c2.css", -"favicon.ico":"favicona9c641bf2b81f0476e876f7c5e375969.ico","my_image.png": -"my_image-231a680f23887d9dd70710ea5efd3c62.png"}} +{"files":{"application-aee4be71f1288037ae78b997df388332edfd246471b533dcedaa8f9fe156442b.js":{"logical_path":"application.js","mtime":"2016-12-23T20:12:03-05:00","size":412383, +"digest":"aee4be71f1288037ae78b997df388332edfd246471b533dcedaa8f9fe156442b","integrity":"sha256-ruS+cfEogDeueLmX3ziDMu39JGRxtTPc7aqPn+FWRCs="}, +"application-86a292b5070793c37e2c0e5f39f73bb387644eaeada7f96e6fc040a028b16c18.css":{"logical_path":"application.css","mtime":"2016-12-23T19:12:20-05:00","size":2994, +"digest":"86a292b5070793c37e2c0e5f39f73bb387644eaeada7f96e6fc040a028b16c18","integrity":"sha256-hqKStQcHk8N+LA5fOfc7s4dkTq6tp/lub8BAoCixbBg="}, +"favicon-8d2387b8d4d32cecd93fa3900df0e9ff89d01aacd84f50e780c17c9f6b3d0eda.ico":{"logical_path":"favicon.ico","mtime":"2016-12-23T20:11:00-05:00","size":8629, +"digest":"8d2387b8d4d32cecd93fa3900df0e9ff89d01aacd84f50e780c17c9f6b3d0eda","integrity":"sha256-jSOHuNTTLOzZP6OQDfDp/4nQGqzYT1DngMF8n2s9Dto="}, +"my_image-f4028156fd7eca03584d5f2fc0470df1e0dbc7369eaae638b2ff033f988ec493.png":{"logical_path":"my_image.png","mtime":"2016-12-23T20:10:54-05:00","size":23414, +"digest":"f4028156fd7eca03584d5f2fc0470df1e0dbc7369eaae638b2ff033f988ec493","integrity":"sha256-9AKBVv1+ygNYTV8vwEcN8eDbxzaequY4sv8DP5iOxJM="}}, +"assets":{"application.js":"application-aee4be71f1288037ae78b997df388332edfd246471b533dcedaa8f9fe156442b.js", +"application.css":"application-86a292b5070793c37e2c0e5f39f73bb387644eaeada7f96e6fc040a028b16c18.css", +"favicon.ico":"favicon-8d2387b8d4d32cecd93fa3900df0e9ff89d01aacd84f50e780c17c9f6b3d0eda.ico", +"my_image.png":"my_image-f4028156fd7eca03584d5f2fc0470df1e0dbc7369eaae638b2ff033f988ec493.png"}} ``` The default location for the manifest is the root of the location specified in @@ -850,7 +852,7 @@ config.assets.compile = true On the first request the assets are compiled and cached as outlined in development above, and the manifest names used in the helpers are altered to -include the MD5 hash. +include the SHA256 hash. Sprockets also sets the `Cache-Control` HTTP header to `max-age=31536000`. This signals all caches between your server and the client browser that this content @@ -1115,7 +1117,7 @@ config.assets.js_compressor = :uglifier ``` NOTE: You will need an [ExecJS](https://github.com/rails/execjs#readme) -supported runtime in order to use `uglifier`. If you are using Mac OS X or +supported runtime in order to use `uglifier`. If you are using macOS or Windows you have a JavaScript runtime installed in your operating system. @@ -1227,35 +1229,25 @@ 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 |