by Gerard Sans |  @gerardsans

Ivy Renderer

for Dummies

Ivy Renderer for Dummies

SANS

GERARD

Developer Advocate AWS

Developer Advocate AWS

International Speaker

Spoken at 130 events in 33 countries

Timeline

Angular v2

Future ready

2016

Renderer (v1)

NgModules (SSR)

Angular v4

Stable and performant

Animations and HttpClient

New Renderer: ViewEngine (v2)

New angular.io website

2017 

Angular v8

Smaller, Faster and Easier to use

Differential Loading

New Renderer: Ivy preview (v3)

Lazy routes dynamic imports

2019 

Why we need a Renderer?

Responsibilities

  • Transform Angular abstractions
  • Create and manipulate DOM
  • Bindings & change detection
  • Create CSS and animations

Benefits

  • Multiplatform support
  • Support: DOM, Web Worker, Mobile, Desktop, SSR
  • Avoid repetitive code
  • Better Performance
import { Component } from '@angular/core';

@Component({
  selector: 'app-root',
  template: `<h1>{{title}}</h1>`
})
export class AppComponent {
  title = "Angular Renderer";
}
app.component.ts

AppComponent

<app-root></app-root>
<script src="app.js"></script>

//app.js
function app(title) {
  const app = document.querySelector("app-root");
  const h1 = document.createElement("h1");
  const text = document.createTextNode(title);
  h1.appendChild(text);
  app.appendChild(h1);
}
app("Angular Renderer"); //bootstrap

Naive Renderer Code

<app-root>
  <h1>Angular Renderer</h1>
</app-root>

Output

Evolution

Renderer v1

ViewEngine v2

Ivy Renderer v3

Rendering Pipeline

ViewEngine vs Ivy Rendering

Template Data

Template HTML

Angular Interpreter

DOM

Template Instructions

Template HTML

DOM

🏁🏎

🐢

import { 
  Component, ɵrenderComponent as renderComponent 
} from '@angular/core';
@Component({
  selector: 'app',
  template: `<h1>{{title}}</h1>`
})
class AppComponent {
  title="Ivy Renderer";
}

renderComponent(AppComponent);

Ivy Component

var AppComponent = /** @class */ (function () {
  AppComponent.ngComponentDef = i0.ɵdefineComponent({
    type: AppComponent,
    selectors: [["app-root"]],
    consts: 2,
    vars: 1,
    template: function AppComponent_Template(rf, ctx) {
      if (rf & 1) {
        i0.ɵelementStart(0, "h1");
        i0.ɵtext(1);
        i0.ɵelementEnd();
      } if (rf & 2) {
        i0.ɵtextBinding(1, i0.ɵinterpolation1("", ctx.title, ""));
      }
    }, encapsulation: 2
  });
}());
export { AppComponent };

Ivy Output

Ivy Renderer

Ivy Rollout Plan

Ivy Compiler

v7

v8

v9

Ivy Runtime

Ivy Preview

Improved Type Checking

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Smaller Bundles

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Backwards Compatible

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Faster Compilation

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Simpler Debugging

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Ivy Features

v9

v9

v9

Smaller Bundles

Angular Hello world app minified uncompressed

Ivy Tree Shaking

  • Template syntax & life-cycle hooks
  • DI, Listeners, Pipes, Queries
  • Content projection
  • Structural directives

Incremental DOM

Source: Medium

<div>

</div>

<h1>

</h1>

Ivy Component Locality 

  • Incremental builds
  • Pre-compiled builds on npm
  • Improved Lazy Loading
  • Faster initial load

Simpler Debugging

Breakpoints in HTML

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Debug Change Detection

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Small Memory Footprint

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Faster Tests

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Bonus Benefits

Bug fixes

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Virtual vs Incremental DOM

Source: Medium

Try it!

Using Angular CLI flag

{
  "compilerOptions": {
    "experimentalDecorators": true,
    ...
  },
  "angularCompilerOptions": {
    "fullTemplateTypeCheck": true,
    "enableIvy": true,
  }
}

tsconfig.json

Enable Ivy Renderer

More

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@ManfredSteyer

Manfred Steyer

@vikerman

Vikram Subramanian

Ivy Renderer Playground