update README

README.md

@@ -1,5 +1,80 @@
 # Pending XHR Puppeteer
 
+<p align="center">
 [![Build Status](https://travis-ci.org/jtassin/pending-xhr-puppeteer.svg?branch=master)](https://travis-ci.org/jtassin/pending-xhr-puppeteer)
+</p>
 
-Work in progress ...
+<p align="center">
+  | <b><a href="#introduction">Introduction</a></b>
+  | <b><a href="#installation">Installation</a></b>
+  | <b><a href="#usage">Usage</a></b>
+  | <b><a href="#contribute">Contribute</a></b> |
+</p>
+
+## Introduction
+
+Pending XHR Puppeteer is a tool that detect when their is xhr requests not yet finished. You can use it to have a xhr requests count or to wait for all xhr requests to be finished.
+
+## Installation
+
+To install with yarn :
+
+```bash
+yarn add pending-xhr-puppeteer -D
+```
+
+To install with npm :
+
+```bash
+npm install pending-xhr-puppeteer --save-dev
+```
+
+## Usage
+
+### wait for all xhr requests to be finished
+
+```javascript
+const puppeteer = require('puppeteer');
+const { PendingXHR } = require('pending-xhr-puppeteer');
+
+const browser = await puppeteer.launch({
+  headless: true,
+  args,
+});
+
+const page = await browser.newPage();
+const pendingXHR = new PendingXHR(page);
+await page.goto(`http://page-with-xhr`);
+// Here all xhr requests are not finished
+await pendingXHR.waitForAllXhrFinished();
+// Here all xhr requests are finished
+```
+
+### Get the number of pending xhr
+
+```javascript
+const puppeteer = require('puppeteer');
+const { PendingXHR } = require('pending-xhr-puppeteer');
+
+const browser = await puppeteer.launch({
+  headless: true,
+  args,
+});
+
+const page = await browser.newPage();
+const pendingXHR = new PendingXHR(page);
+await page.goto(`http://page-with-xhr`);
+console.log(pendingXHR.pendingXhrCount());
+// Display the number of xhr pending
+```
+
+## Contribute
+
+```bash
+git clone https://github.com/jtassin/pending-xhr-puppeteer.git
+cd pending-xhr-puppeteer
+yarn
+yarn test
+```
+
+Merge request and issues are welcome.