logux-client v0.2.10
Logux Client
Logux is a client-server communication protocol. It synchronizes action between clients and server logs.
This 8 KB library allows you to put action (which look similar to Redux actions) to a local log and synchronize them with Logux Server and thus with every other client being online.
This is a low-level client API. Redux-like API, which is supposed to be more suitable for most of developers, is coming soon.
See also Logux Status for UX best practices.
Getting Started
Add Logux to your Project
This project uses npm package manager. So you will need Webpack or Browserify to build a JS bundle for browsers.
Install Logux Client:
npm install --save logux-client
Add Credentials to the Client
You should use a secret token for authentication at the Logux server.
We suggest adding a special token
column to the users table of your
application and filling it with auto-generated random strings.
When the user requests index.html
from your app, HTTP server would add
<meta>
tags with a token and Logux server URL.
<meta name="user" content="<%= user.id %>" />
<meta name="token" content="<%= user.token %>" />
<meta name="server" content="wss://example.com:1337" />
However, it is not the only possible way for communication. You could also use cookies or tools like Gon.
Create Logux Client
Create Logux Client instance in your client-side JS;
onready
event handler seems to be a good place for this:
var CrossTabClient = require('logux-client/cross-tab-client')
var user = document.querySelector('meta[name=user]')
var token = document.querySelector('meta[name=token]')
var server = document.querySelector('meta[name=server]')
var logux = new CrossTabClient({
credentials: token.content,
subprotocol: '1.0.0',
server: server.content,
userId: user.content
})
logux.start()
If you sure, that your application will not be run in separated browser
tabs (for instance, you are developing a app for kiosk), you can use
Client
instead of CrossTabClient
.
Process Actions
Add callbacks for new actions coming to the client log
(from server, other clients or local logux.log.add
call):
logux.on('add', function (action, meta) {
if (action.type === 'CHANGE_TITLE') {
var user = document.querySelector('.article[data-id=' + action.article + ']')
if (user) {
document.querySelector('.article__title').innerText = action.title
}
}
})
Read logux-core
docs for logux.log
API.
Adding Actions
When you need to send information to server, just add an action to log:
submit.addEventListener('click', function () {
logux.log.add({
type: 'CHANGE_TITLE',
article: articleId.value,
title: titleField.value
}, {
reasons: ['lastValue']
})
}, false)
Show Connection State
Notify user if connection was lost:
var favicon = document.querySelector('link[rel~="icon"]')
var notice = document.querySelector('.offline-notice')
logux.sync.on('state', function () {
if (logux.sync.connected) {
favicon.href = '/favicon.ico'
notice.classList.add('.offline-notice_hidden')
} else {
favicon.href = '/offline.ico'
notice.classList.remove('.offline-notice_hidden')
}
})
Cross-Tab Communication
If user will open website in two different browser tabs, Logux anyway will have single storage, so JS in tabs will have same actions.
You can set tab
key in metadata to isolate action only in current tab:
app.log.add(action, { tab: app.id })