diff --git a/public/docs/ts/latest/cookbook/_data.json b/public/docs/ts/latest/cookbook/_data.json index 123c9a1ce7..1aed135fa8 100644 --- a/public/docs/ts/latest/cookbook/_data.json +++ b/public/docs/ts/latest/cookbook/_data.json @@ -7,7 +7,7 @@ "aot-compiler": { "title": "Ahead-of-Time Compilation", - "intro": "Learn how to use Ahead-of-time compilation." + "intro": "Learn how to use ahead-of-time compilation." }, "ajs-quick-reference": { diff --git a/public/docs/ts/latest/cookbook/aot-compiler.jade b/public/docs/ts/latest/cookbook/aot-compiler.jade index 50c4ba8786..dab6b7e19c 100644 --- a/public/docs/ts/latest/cookbook/aot-compiler.jade +++ b/public/docs/ts/latest/cookbook/aot-compiler.jade @@ -1,38 +1,48 @@ include ../_util-fns :marked - This cookbook describes how to radically improve performance by compiling _Ahead of Time_ (AOT) + This cookbook describes how to radically improve performance by compiling _ahead-of-time_ (AOT) during a build process. a#toc :marked - ## Table of Contents - * [Overview](#overview) - * [_Ahead-of-Time_ vs _Just-in-Time_](#aot-jit) - * [Compile with AOT](#compile) - * [Bootstrap](#bootstrap) - * [Tree Shaking](#tree-shaking) - * [Load the bundle](#load) - * [Serve the app](#serve) - * [Workflow and convenience script](#workflow) - * [Source Code](#source-code) - * [Tour of Heroes](#toh) + # Contents + - [Overview](overview) + - [Ahead-of-time (AOT) vs just-in-time (JIT)](#aot-jit) + - [Why do AOT compilation?](#why-aot) + - [Compile with AOT](#compile) + - [Bootstrap](#bootstrap) + - [Tree shaking](#tree-shaking) + - [Rollup](#rollup) + - [Rollup Plugins](#rollup-plugins) + - [Run Rollup](#run-rollup) + - [Load the bundle](#load) + - [Serve the app](#serve) + - [AOT QuickStart source code](#source-code) + - [Workflow and convenience script](#workflow) + - [Develop JIT along with AOT](#run-jit) + - [Tour of Heroes](#toh) + - [JIT in development, AOT in production](#jit-dev-aot-prod) + - [Tree shaking](#shaking) + - [Running the application](#running-app) + - [Inspect the Bundle](#inspect-bundle) + a#overview .l-main-section :marked ## Overview - An Angular application consist largely of components and their HTML templates. + An Angular application consists largely of components and their HTML templates. Before the browser can render the application, the components and templates must be converted to executable JavaScript by the _Angular compiler_. .l-sub-section :marked Watch compiler author Tobias Bosch explain the Angular Compiler at AngularConnect 2016. :marked - You can compile the app in the browser, at runtime, as the application loads, using the **_Just-in-Time_ (JIT) compiler**. + You can compile the app in the browser, at runtime, as the application loads, using the **_just-in-time_ (JIT) compiler**. This is the standard development approach shown throughout the documentation. - It's great .. but it has shortcomings. + It's great but it has shortcomings. JIT compilation incurs a runtime performance penalty. Views take longer to render because of the in-browser compilation step. @@ -41,22 +51,23 @@ a#overview Bigger apps take longer to transmit and are slower to load. Compilation can uncover many component-template binding errors. - JIT compilation discovers them at runtime which is later than we'd like. + JIT compilation discovers them at runtime, which is late in the process. - The **_Ahead-of-Time_ (AOT) compiler** can catch template errors early and improve performance - by compiling at build time as you'll learn in this chapter. + The **_ahead-of-time_ (AOT) compiler** can catch template errors early and improve performance + by compiling at build time. a#aot-jit .l-main-section :marked - ## _Ahead-of-time_ (AOT) vs _Just-in-time_ (JIT) + ## _Ahead-of-time_ (AOT) vs _just-in-time_ (JIT) There is actually only one Angular compiler. The difference between AOT and JIT is a matter of timing and tooling. With AOT, the compiler runs once at build time using one set of libraries; - With JIT it runs every time for every user at runtime using a different set of libraries. - - ### Why do AOT compilation? + with JIT it runs every time for every user at runtime using a different set of libraries. +a#why-aot +:marked + ## Why do AOT compilation? *Faster rendering* @@ -65,7 +76,7 @@ a#aot-jit *Fewer asynchronous requests* - The compiler _inlines_ external html templates and css style sheets within the application JavaScript, + The compiler _inlines_ external HTML templates and CSS style sheets within the application JavaScript, eliminating separate ajax requests for those source files. *Smaller Angular framework download size* @@ -91,9 +102,9 @@ a#compile :marked ## Compile with AOT - ### Prepare for offline compilation + Preparing for offline compilation takes a few simple steps. Take the Setup as a starting point. - A few minor changes to the lone `app.component` lead to these two class and html files: + A few minor changes to the lone `app.component` lead to these two class and HTML files: +makeTabs( `cb-aot-compiler/ts/src/app/app.component.html, @@ -114,8 +125,8 @@ code-example(language="none" class="code-shell"). `ngc` is a drop-in replacement for `tsc` and is configured much the same way. `ngc` requires its own `tsconfig.json` with AOT-oriented settings. - Copy the original `src/tsconfig.json` to a file called `tsconfig-aot.json` (on the project root), - then modify it to look as follows. + Copy the original `src/tsconfig.json` to a file called `tsconfig-aot.json` on the project root, + then modify it as follows. +makeExample('cb-aot-compiler/ts/tsconfig-aot.json', null, 'tsconfig-aot.json')(format='.') @@ -125,23 +136,23 @@ code-example(language="none" class="code-shell"). This is important as explained later in the [Tree Shaking](#tree-shaking) section. What's really new is the `ngc` section at the bottom called `angularCompilerOptions`. - Its `"genDir"` property tells the compiler + Its `genDir` property tells the compiler to store the compiled output files in a new `aot` folder. The `"skipMetadataEmit" : true` property prevents the compiler from generating metadata files with the compiled application. Metadata files are not necessary when targeting TypeScript files, so there is no reason to include them. :marked - ***Component-relative Template URLS*** + ***Component-relative template URLS*** - The AOT compiler requires that `@Component` URLS for external templates and css files be _component-relative_. + The AOT compiler requires that `@Component` URLS for external templates and CSS files be _component-relative_. That means that the value of `@Component.templateUrl` is a URL value _relative_ to the component class file. For example, an `'app.component.html'` URL means that the template file is a sibling of its companion `app.component.ts` file. While JIT app URLs are more flexible, stick with _component-relative_ URLs for compatibility with AOT compilation. :marked - ### Compiling the application + ***Compiling the application*** Initiate AOT compilation from the command line using the previously installed `ngc` compiler by executing: code-example(language="none" class="code-shell"). @@ -154,7 +165,8 @@ code-example(language="none" class="code-shell"). :marked `ngc` expects the `-p` switch to point to a `tsconfig.json` file or a folder containing a `tsconfig.json` file. - After `ngc` completes, look for a collection of _NgFactory_ files in the `aot` folder (the folder specified as `genDir` in `tsconfig-aot.json`). + After `ngc` completes, look for a collection of _NgFactory_ files in the `aot` folder. + The `aot` folder is the directory specified as `genDir` in `tsconfig-aot.json`. These factory files are essential to the compiled application. Each component factory creates an instance of the component at runtime by combining the original class file @@ -162,8 +174,8 @@ code-example(language="none" class="code-shell"). Note that the original component class is still referenced internally by the generated factory. .l-sub-section :marked - The curious can open the `aot/app.component.ngfactory.ts` to see the original Angular template syntax - in its intermediate, compiled-to-TypeScript form. + The curious can open `aot/app.component.ngfactory.ts` to see the original Angular template syntax + compiled to TypeScript, its intermediate form. JIT compilation generates these same _NgFactories_ in memory where they are largely invisible. AOT compilation reveals them as separate, physical files. @@ -178,7 +190,7 @@ a#bootstrap :marked ## Bootstrap - The AOT path changes application bootstrapping. + The AOT approach changes application bootstrapping. Instead of bootstrapping `AppModule`, you bootstrap the application with the generated module factory, `AppModuleNgFactory`. @@ -200,44 +212,46 @@ a#bootstrap ) :marked - Be sure to recompile with `ngc`! + Be sure to [recompile](#compiling-aot) with `ngc`! a#tree-shaking :marked - ## Tree Shaking + ## Tree shaking - AOT compilation sets the stage for further optimization through a process called _Tree Shaking_. - A Tree Shaker walks the dependency graph, top to bottom, and _shakes out_ unused code like - dead needles in a Christmas tree. + AOT compilation sets the stage for further optimization through a process called _tree shaking_. + A tree shaker walks the dependency graph, top to bottom, and _shakes out_ unused code like + dead leaves in a tree. - Tree Shaking can greatly reduce the downloaded size of the application + Tree shaking can greatly reduce the downloaded size of the application by removing unused portions of both source and library code. In fact, most of the reduction in small apps comes from removing unreferenced Angular features. For example, this demo application doesn't use anything from the `@angular/forms` library. - There is no reason to download Forms-related Angular code and tree shaking ensures that you don't. + There is no reason to download forms-related Angular code and tree shaking ensures that you don't. - Tree Shaking and AOT compilation are separate steps. - Tree Shaking can only target JavaScript code. + Tree shaking and AOT compilation are separate steps. + Tree shaking can only target JavaScript code. AOT compilation converts more of the application to JavaScript, - which in turn makes more of the application "Tree Shakable". + which in turn makes more of the application "tree shakable". +a#rollup +:marked ### Rollup - This cookbook illustrates a Tree Shaking utility called _Rollup_. + This cookbook illustrates a tree shaking utility called _Rollup_. Rollup statically analyzes the application by following the trail of `import` and `export` statements. It produces a final code _bundle_ that excludes code that is exported, but never imported. - Rollup can only Tree Shake `ES2015` modules which have `import` and `export` statements. + Rollup can only tree shake `ES2015` modules which have `import` and `export` statements. .l-sub-section :marked Recall that `tsconfig-aot.json` is configured to produce `ES2015` modules. It's not important that the code itself be written with `ES2015` syntax such as `class` and `const`. What matters is that the code uses ES `import` and `export` statements rather than `require` statements. :marked - Install the Rollup dependencies with this command: -code-example(format='.'). + In the terminal window, install the Rollup dependencies with this command: +code-example(language="none" class="code-shell"). npm install rollup rollup-plugin-node-resolve rollup-plugin-commonjs rollup-plugin-uglify --save-dev :marked Next, create a configuration file (`rollup-config.js`) @@ -246,35 +260,40 @@ code-example(format='.'). +makeExample('cb-aot-compiler/ts/rollup-config.js', null, 'rollup-config.js')(format='.') :marked - It tells Rollup that the app entry point is `src/app/main.js` . + This config file tells Rollup that the app entry point is `src/app/main.js` . The `dest` attribute tells Rollup to create a bundle called `build.js` in the `dist` folder. It overrides the default `onwarn` method in order to skip annoying messages about the AOT compiler's use of the `this` keyword. - Then there are plugins. + The next section covers the plugins in more depth. +a#rollup-plugins :marked ### Rollup Plugins Optional plugins filter and transform the Rollup inputs and output. *RxJS* + Rollup expects application source code to use `ES2015` modules. Not all external dependencies are published as `ES2015` modules. In fact, most are not. Many of them are published as _CommonJS_ modules. - The _RxJs_ observable library is an essential Angular dependency published as an ES5 JavaScript _CommonJS_ module. + The _RxJs_ Observable library is an essential Angular dependency published as an ES5 JavaScript _CommonJS_ module. - Luckily there is a Rollup plugin that modifies _RxJs_ + Luckily, there is a Rollup plugin that modifies _RxJs_ to use the ES `import` and `export` statements that Rollup requires. - Rollup then preserves in the final bundle the parts of `RxJS` referenced by the application. + Rollup then preserves the parts of `RxJS` referenced by the application + in the final bundle. Using it is straigthforward. Add the following to + the `plugins` !{_array} in `rollup-config.js`: +makeExample('cb-aot-compiler/ts/rollup-config.js','commonjs','rollup-config.js (CommonJs to ES2015 Plugin)')(format='.') :marked *Minification* - Rollup Tree Shaking reduces code size considerably. Minification makes it smaller still. - This cookbook relies on the _uglify_ Rollup plugin to minify and mangle the code. + Rollup tree shaking reduces code size considerably. Minification makes it smaller still. + This cookbook relies on the _uglify_ Rollup plugin to minify and mangle the code. + Add the following to the `plugins` !{_array}: +makeExample('cb-aot-compiler/ts/rollup-config.js','uglify','rollup-config.js (CommonJs to ES2015 Plugin)')(format='.') @@ -283,25 +302,26 @@ code-example(format='.'). In a production setting, you would also enable gzip on the web server to compress the code into an even smaller package going over the wire. +a#run-rollup :marked ### Run Rollup Execute the Rollup process with this command: -code-example(format='.'). +code-example(language="none" class="code-shell"). node_modules/.bin/rollup -c rollup-config.js .l-sub-section :marked Windows users should surround the `rollup` command in double quotes: - code-example(format='.'). + code-example(language="none" class="code-shell"). "node_modules/.bin/rollup" -c rollup-config.js :marked a#load .l-main-section :marked - ## Load the Bundle + ## Load the bundle Loading the generated application bundle does not require a module loader like SystemJS. Remove the scripts that concern SystemJS. - Instead, load the bundle file using a single `script` tag **_after_** the `` tag: + Instead, load the bundle file using a single `