platform/packages/html/README.md

# Angel3 HTML

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A plug-in that allows you to return `belatuk_html_builder` AST's from request handlers, and have them sent as HTML automatically.

[`package:belatuk_html_builder`](https://pub.dev/packages/belatuk_html_builder) is a simple virtual DOM library with a handy Dart DSL that makes it easy to build HTML AST's:

```dart
import 'package:belatuk_html_builder/elements.dart';

Node myDom = html(lang: 'en', c: [
  head(c: [
    meta(name: 'viewport', content: 'width=device-width, initial-scale=1'),
    title(c: [
      text('html_builder example page')
    ]),
  ]),
  body(c: [
    h1(c: [
      text('Hello world!'),
    ]),
  ]),
]);
```

This plug-in means that you can now `return` these AST's, and Angel will automatically send them to clients. Ultimately, the implication is that you can use `belatuk_html_builder` as a substitute for a templating system within Dart. With [hot reloading](https://pub.dev/packages/angel3_hot), you won't even need to reload your server (as it should be).

## Installation

In your `pubspec.yaml`:

```yaml
dependencies:
  angel3_html: ^6.0.0
```

## Usage

The `renderHtml` function does all the magic for you.

```dart
configureServer(Angel app) async {
  // Wire it up!
  app.fallback(renderHtml());
  
  // You can pass a custom StringRenderer if you need more control over the output.
  app.fallback(renderHtml(renderer: new StringRenderer(html5: false)));
  
  app.get('/greet/:name', (RequestContext req) {
    return html(lang: 'en', c: [
     head(c: [
       meta(name: 'viewport', content: 'width=device-width, initial-scale=1'),
       title(c: [
         text('Greetings!')
       ]),
     ]),
     body(c: [
       h1(c: [
         text('Hello, ${req.params['id']}!'),
       ]),
     ]),
   ]);
  });
}
```

By default, `renderHtml` will ignore the client's `Accept` header. However, if you pass `enforceAcceptHeader` as `true`, then a `406 Not Acceptable` error will be thrown if the client doesn't accept `*/*` or `text/html`.

```dart
configureServer(Angel app) async {
  // Wire it up!
  app.fallback(renderHtml(enforceAcceptHeader: true));
  
  // ...
}
```