https://github.com/interledgerjs/express-web-monetization
https://github.com/interledgerjs/express-web-monetization
Last synced: 30 days ago
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- Host: GitHub
- URL: https://github.com/interledgerjs/express-web-monetization
- Owner: interledgerjs
- Created: 2018-04-06T17:22:50.000Z (about 7 years ago)
- Default Branch: master
- Last Pushed: 2018-04-25T23:11:40.000Z (about 7 years ago)
- Last Synced: 2025-03-30T23:31:39.802Z (2 months ago)
- Language: JavaScript
- Size: 3.69 MB
- Stars: 2
- Watchers: 2
- Forks: 3
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
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README
# Express Web Monetization
> Charge for resources and API calls with web monetization
- [Overview](#overview)
- [Example Code](#example-code)
- [Try it Out](#try-it-out)
- [Prerequisites](#prerequisites)
- [Install and Run](#install-and-run)
- [API Docs](#api-docs)
- [Constructor](#constructor)
- [Receiver](#receiver)
- [Paid](#paid)
## Overview
Using [Interledger](https://interledger.org) for payments, [Web
Monetization](https://github.com/interledger/rfcs/blob/master/0028-web-monetization/0028-web-monetization.md#web-monetization)
allows sites to monetize their traffic without being tied to an ad network. And
because payments happen instantly, they can also be tracked on the server-side
to unlock exclusive content or paywalls.
`express-web-monetization` makes this easy by providing middleware for your
[Express](https://expressjs.com) application. Charging your users is as easy as putting
`request.spend(100)` in your route handler. No need to convince them to
buy a subscription or donate.
## Example Code
Below is an example of some of the functions that you would use to create
paywalled content. For a complete and working example, look at the next
section.
```js
'use strict'
const express = require('express')
const app = express()
const server = require('http').Server(app)
const router = express.Router()
const ExpressWebMonetization = require('express-web-monetization')
const monetizer = new ExpressWebMonetization()
const cookieParser = require('cookie-parser')
const path = require('path')
// This is the SPSP endpoint that lets you receive ILP payments. Money that
// comes in is associated with the :id
router.get(monetizer.receiverEndpointUrl, monetizer.receive())
// This endpoint charges 100 units to the user with :id
// If awaitBalance is set to true, the call will stay open until the balance is sufficient. This is convenient
// for making sure that the call doesn't immediately fail when called on startup.
router.get('/content/', async (req, res) => {
await req.awaitBalance(100)
req.spend(100)
// load content
})
router.get('/client.js', async (req, res) => {
res.send(monetizer.serverClient())
})
router.get('/', (req, res) => {
res.sendFile(path.join(__dirname + '/index.html'))
})
app.use(cookieParser())
app.use(monetizer.mount())
app.use('/', router)
server.listen(8080)
```
The client side code to support this is very simple too:
```html
var monetizerClient = new MonetizerClient();
monetizerClient.start()
```
## Try it out
This repo comes with an example server that you can run. It serves a page that has a single paywalled image on it.
The server waits for money to come in and then shows the image.
### Prerequisites
- You should be running [Moneyd](https://github.com/interledgerjs/moneyd-xrp)
for Interledger payments. [Local
mode](https://github.com/interledgerjs/moneyd-xrp#local-test-network) will work
fine.
- Build and install the [Minute](https://github.com/sharafian/minute)
extension. This adds Web Monetization support to your browser.
### Install and Run
```sh
git clone https://github.com/andywong418/express-web-monetization.git
cd express-web-monetization
npm install
DEBUG=* node example/index.js
```
Now go to [http://localhost:8080](http://localhost:8080), and watch the server
logs.
If you configured Minute and Moneyd correctly, you'll start to see that money
is coming in. Once the user has paid 100 units, the example image will load on
the page.
## API Docs
### Constructor
```ts
new ExpressWebMonetization(opts: Object | void): ExpressWebMonetization
```
Create a new `ExpressWebMonetization` instance.
- `opts.plugin` - Supply an ILP plugin. Defaults to using Moneyd.
- `opts.maxBalance` - The maximum balance that can be associated with any user. Defaults to `Infinity`.
- `opts.receiveEndpointUrl` - The endpoint in your Express route configuration that specifies where a user pays streams PSK packets to your site. Defaults to `/__monetizer/{id}` where `{id}` is the server generated ID (stored in the browser as a cookie).
- `opts.cookieName` - The cookie key name for your server generated payer ID. Defaults to `__monetizer`.
- `opts.cookieOptions` - Cookie configurations for Express. See [Express response setting cookies options](https://expressjs.com/en/api.html) for more details! Only defaults are `httpOnly: false`
### Receiver
```ts
instance.receiver(): Function
```
Returns a Express middleware for setting up Interledger payments with
[SPSP](https://github.com/sharafian/ilp-protocol-spsp) (used in Web
Monetization).
### Client constructor options
```ts
new MonetizerClient(opts: Object | void): MonetizerClient
```
Creates a new `MonetizerClient` instance.
- `opts.url` - The url of the server that is registering the ExpressWebMonetization plugin. Defaults to `new URL(window.location).origin`
- `opts.cookieName` - The cookie key name that will be saved in your browser. Defaults to `__monetizer`. This MUST be the same has `opts.cookieName` in the server configuration.
- `opts.receiveEndpointUrl` - The endpoint where users of the site can start streaming packets via their browser extension or through the browser API. Defaults to `opts.url + '__monetizer/:id'` where id is the server generated payer ID. This MUST be the same has `opts.receiverEndpointUrl` in the server configuration.
### Middleware for cookies
```ts
WebMonetizationMiddleware(monetizer: ExpressWebMonetization)
```
This middleware allows cookies to be generated (or just sent if already set) from the server to the client. It also injects the `awaitBalance` and `spend` methods described below. Note that your app must require and use the `cookie-parser` middleware before it uses the `WebMonetizationMiddleware`.
### Charging users
The methods `req.spend()` and `req.awaitBalance()` are available to use inside handlers.
```ts
req.spend(amount): Function
```
Specifies how many units to charge the user.
```ts
req.awaitBalance(amount): Function
```
Waits until the user has sufficient balance to pay for specific content.
`awaitBalance` can be useful for when a call is being done at page start.
Rather than immediately failing because the user hasn't paid, the server will
wait until the user has paid the specified price.