https://github.com/Tychobra/polished-load-balancer

https://github.com/Tychobra/polished-load-balancer

Last synced: 28 days ago
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• Host: GitHub
• URL: https://github.com/Tychobra/polished-load-balancer
• Owner: Tychobra
• License: mit
• Created: 2022-03-14T21:59:53.000Z (over 2 years ago)
• Default Branch: master
• Last Pushed: 2024-04-05T18:17:44.000Z (7 months ago)
• Last Synced: 2024-09-19T05:40:22.961Z (about 2 months ago)
• Language: JavaScript
• Size: 334 KB
• Stars: 2
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE.md

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• jimsghstars - Tychobra/polished-load-balancer - (JavaScript)

README

        
# polished-load-balancer

`polished-load-balancer` is a simple load balancer for a single Shiny app. 

* it runs several instances of your Shiny app to overcome the single-process limitation of a standard shiny app

* new Shiny app instances are automatically started and stopped as your app experiences more and less traffic

* it is a middleware for a Node.js [Express](https://expressjs.com) application, so it can be easily extended

## Installation

```terminal

npm install polished-load-balancer

```

## Simple Example

The following example will serve a Shiny app located in the `/srv/shiny_app` folder:

```nodejs

# server.js

import express from 'express'

import polishedLoadBalancer from 'polished-load-balancer'

const plb = await polishedLoadBalancer({

  appDir: "/srv/shiny_app",

  maxSessions: 1

})

const app = express()

app.use(plb)

app.listen(8080)

```

If you run the above server using `node server.js`, your auto scaling Shiny app will be available at `http://localhost:8080`.

## Options

The load balancer middleware is created by `polishedLoadBalancer(options)`. `options` is an object with

the following configurable properties:

* **appDir:** string - the path of the folder containing the Shiny app. 

* **maxSessions:** integer > 0 - the max number of active sessions per Shiny app instance before starting up a new Shiny app instance.  New Shiny app instances are automatically scaled up and down as each running Shiny app reaches this maxSessions number of sessions.

## Prior Work

This package was adapted from [node-shiny-proxy](https://github.com/martinv13/node-shiny-proxy) by Martin Vergier