Rendering

You can render views by calling the View.render method. The method accepts the template path relative to the views directory and the data object to pass to the template and always returns a string value.

import View from '@ioc:Adonis/Core/View'
const html = await View.render('welcome', {
greeting: 'Hello'
})

During the HTTP requests, it is recommended to use the ctx.view object instead of the top-level import.

The ctx.view is an isolated instance of the View module created for that specific request and shares the request-specific data with the templates.

Route.get('/', async ({ view }) => {
const html = await view.render('welcome', {
greeting: 'Hello'
})
return html
})

Rendering modes

Edge exposes both the sync and the async API for rendering views. We recommend using the async API. In async mode, the I/O operations performed by Edge do not block the Node.js event loop.

In the following example:

  • The user.edge file is read synchronously from the disk.
  • Any internal references to load partials or components will be synchronous too.
  • The template cannot use the await keyword. For example: {{ await getUser() }} will NOT work.
view.renderSync('user', {
getUser: async () => {},
})

Whereas the view.render method is free from all the caveats of synchronous rendering.

await view.render('user', {
getUser: async () => {},
})

Disks

Edge allows you to specify multiple root directories for finding the templates. We call this concept a mounting disk.

We mount the ./resources/views directory as the default disk for you implicitly. However, if required, you can also mount additional directories, each with a unique name.

You can write the following code inside a preload file .

start/views.ts
import View from '@ioc:Adonis/Core/View'
import Application from '@ioc:Adonis/Core/Application'
View.mount('material', Application.resourcesPath('themes/material'))
View.mount('elegant', Application.resourcesPath('themes/elegant'))

You can render the views from the named disks by prefixing the disk name.

// renders themes/material/user.edge
view.render('material::user')
// renders themes/elegant/user.edge
view.render('elegant::user')

Similarly, you can prefix the disk name when including partials or components.

@include('material::header')
@component('material::button')
@end

In-memory templates

Edge allows you to register in-memory templates without creating any file on the disk. You may find it helpful when you want to provide some templates as part of an npm package.

import View from '@ioc:Adonis/Core/View'
View.registerTemplate('uikit/button', {
template: `
<button {{ $props.serializeExcept(['title']) }}>
{{ title }}
</button>
`,
})

You can render the template directly or use it as a component with the exact name given to the View.registerTemplate method.

@!component('uikit/button', {
title: 'Signup',
class: ['btn', 'btn-primary'],
id: 'signup'
})

The in-memory templates are given preference over the on-disk templates in case of a path conflict.

Rendering raw string

Edge also exposes the API to render raw string values directly as a template. However do note, that raw strings do not enjoy the benefits of template caching as there are not associated with a unique path.

await View.renderRaw(
`
<p> Hello {{ username }} </p>
`,
{
username: 'virk',
}
)

Use the renderRawSync method to render the raw string synchronously.

View.renderRawSync(
`
<p> Hello {{ username }} </p>
`,
{
username: 'virk',
}
)

View renderer instances

Views in Edge are rendered using the ViewRenderer class. So every time you run the View.render method, we create a new instance of the ViewRenderer and then call the render method on it.

You can also get the renderer instance by calling the View.getRenderer() method and use the share method to share data with the view.

import View from '@ioc:Adonis/Core/View'
const view = View.getRenderer()
view.share({ url: '/', user: auth.user })
await view.render('home')

The ctx.view object is an instance of the ViewRenderer class.

Caching

Compiling a template to a JavaScript function is a time-consuming process, and hence it is recommended to cache the compiled templates in production.

You can control the template caching using the CACHE_VIEWS environment variable. Just make sure to set the value to true in the production environment.

CACHE_VIEWS=true

All of the templates are cached within the memory. Currently, we do not have any plans to support on-disk caching since the value provided for the efforts is too low.

The raw text does not take up too much space, and even keeping thousands of pre-compiled templates in memory should not be a problem.