README

Barleytea.js

Barleytea.js strives to be a transparent, familiar framework by:

keeping things as close to vanilla js as possible
providing a lot of the functionality you like from js frameworks you've worked with
in small(-ish), readable chunks so that you can modify/replace/copy at will
with removable parts in case you don't need all of it

See our Design Goals for more details on what this framework strives for.

It's currently about 3.1 KB minified/gzipped.

Features

Framework includes:

custom elements and lifecycle functions
data binding
slots
automatic registering and cleanup of listeners
"memoized-once" functions for computed values
shared state management
~~Routing~~ (No routing because I personally don't prefer to use browser-side routing, but if that's your thing, maybe consider using RLite

Templating includes:

V-DOM-less DOM diffing
xss protection
element property setters
self-closing tags
keyed renders

Also:

Use defined elements anywhere, no need to render it within an "app" element
Same function signature as customElements.define to minimize framework-specific knowledge

Not interested in all of that? Pick and choose what you want

To use:

Here's a customary to-do list with Barleytea.js:

TodoList.js

class TodoList extends HTMLElement {
  state = {
    todos: ['write tests', 'debug code']
  }

  // this makes it possible to quickly add a todo on an "Enter" keypress
  handleKeyDown = e => {
    if (e.key === 'Enter' && e.target.value) {
      e.preventDefault()
      this.addTodo(e.target.value)
      e.target.value = ''
    }
  }

  // add a new todo with the given string value
  addTodo = todo => {
    this.state.todos = [...this.state.todos, todo]
  }

  // remove a todo by index
  removeTodo = idx => {
    this.state.todos = [...this.state.todos.slice(0, idx), ...this.state.todos.slice(idx + 1)]
  }

  render({ html, keyed, state }) {
    return html`
      <div>
        <h1>To dos:</h1>
        <input 
          placeholder='Enter a new item here' 
          .onkeydown=${this.handleKeyDown}>
        <button 
          .onclick=${this.addTodo}>Add</button>
        <ul>
          ${state.todos.map((todo, idx) => keyed(idx)`
            <li>
              ${todo} 
              <button
                .onclick=${() => this.removeTodo(idx)}>X</button>
            </li>`
          )}
        </ul>
      </div>
    `
  }
}

define('todo-list', TodoList)

index.html

<html>
  <script src="barleytea.js"></script>
  <script src="TodoList.js"></script>
  <body>
    <todo-list />
  </body>
</html>

See it in action here

We're using the vanilla.js way to define a custom element but instead of using customElements.define, we're using our own define function. Within the class definition, we have some magic attributes:

state is for props with data-binding
cached is for functions that only re-run when their arguments change
render will re-render the element (only repaints what changed- see templating)
listeners defines all auto-added listeners, and the window object within it defines listeners to attach to the window
if you have any slot elements within your class, you can find them in this.slots (slots.default holds all unnamed slots, while, for example, slots[mySlotName] will hold the slot named "mySlotName")
for shared state, we have a createStore function you can read more about here

To Download

You can download it from here for now, or get the whole thing from /public/barleytea.js in this repo.

Performance

Seems to run DBMonster pretty quickly, even slightly faster than React, on my machine at least. You can read more about that here

Tests

The template code tests can be run [here]((https://andrewfulrich.gitlab.io/barleytea/test/SpecRunner.html)

There's a lot of code examples in the docs that demonstrate each part of the framework.

To run the tests locally (as well as distromaker etc.), you can npm install and then npm run local

Contribution Steps

Here are some general (not always applicable) steps for contributing back changes to the UI.

Make the change in the code. If it's in the templating, change public/parts/templating.js. If it's in the element framework, change public/parts/framework.js.
Run distroMaker and tests locally with npm install; npm run local and go to http://localhost:3000/public/distroMaker.html and http://localhost:3000/public/test/SpecRunner.html
Make a test for the change
Copy the distroMaker output over to barleytea.js and barleytea-common.js
If it's a new feature, make a new section in the docs explaining the new feature and usage, along with a working code example.
Make a Merge Request

Usage no npm install needed!