Add header pioritizing, update README, example and added test case.

README.md

@@ -1,6 +1,6 @@
 # request-ip
 
-A tiny Node.js module for retrieving a request's IP address. 
+A tiny Node.js module for retrieving a request's IP address.
 
 ![](https://nodei.co/npm/request-ip.png?downloads=true&cacheBust=3)
 
@@ -12,53 +12,56 @@ A tiny Node.js module for retrieving a request's IP address.
 ## Installation
 
 Yarn
+
 ```
 yarn add request-ip
 ```
 
 npm
+
 ```bash
 npm install request-ip --save
 ```
-    
+
 ## Getting Started
 
 ```javascript
 const requestIp = require('request-ip');
 
 // inside middleware handler
-const ipMiddleware = function(req, res, next) {
-    const clientIp = requestIp.getClientIp(req); 
-    next();
+const ipMiddleware = function (req, res, next) {
+  const clientIp = requestIp.getClientIp(req);
+  next();
 };
 
-// on localhost you'll see 127.0.0.1 if you're using IPv4 
+// on localhost you'll see 127.0.0.1 if you're using IPv4
 // or ::1, ::ffff:127.0.0.1 if you're using IPv6
 ```
 
 ### As Connect Middleware
 
 ```javascript
 const requestIp = require('request-ip');
-app.use(requestIp.mw())
+app.use(requestIp.mw());
 
-app.use(function(req, res) {
-    const ip = req.clientIp;
-    res.end(ip);
+app.use(function (req, res) {
+  const ip = req.clientIp;
+  res.end(ip);
 });
 ```
 
 To see a full working code for the middleware, check out the [examples](https://github.com/pbojinov/request-ip/tree/master/examples) folder.
 
-The connect-middleware also supports retrieving the ip address under a custom attribute name, which also works as a container for any future settings. 
+The connect-middleware also supports retrieving the ip address under a custom attribute name, which also works as a container for any future settings.
+And it also support header check priority.
 
 ## How It Works
 
 It looks for specific headers in the request and falls back to some defaults if they do not exist.
 
 The user ip is determined by the following order:
 
-1. `X-Client-IP`  
+1. `X-Client-IP`
 2. `X-Forwarded-For` (Header may return multiple IP addresses in the format: "client IP, proxy 1 IP, proxy 2 IP", so we take the first one.)
 3. `CF-Connecting-IP` (Cloudflare)
 4. `Fastly-Client-Ip` (Fastly CDN and Firebase hosting header when forwared to a cloud function)
@@ -78,8 +81,7 @@ If an IP address cannot be found, it will return `null`.
 
 ## Samples Use Cases
 
-* Getting a user's IP for geolocation.
-
+- Getting a user's IP for geolocation.
 
 ## Running the Tests
 

examples/connect-middleware-custom.js

@@ -9,22 +9,32 @@ var requestIp = require('request-ip');
 
 // you can override which attirbute the ip will be set on by
 // passing in an options object with an attributeName
-app.use(requestIp.mw({ attributeName : 'myCustomAttributeName' }))
+app.use(
+    requestIp.mw({
+        attributeName: 'myCustomAttributeName',
+        prioritize: ['x-real-ip'],
+    }),
+);
 
 // respond to all requests
-app.use(function(req, res) {
-
+app.use(function (req, res) {
     // use our custom attributeName that we registered in the middleware
     var ip = req.myCustomAttributeName;
     console.log(ip);
 
     // https://nodejs.org/api/net.html#net_net_isip_input
     var ipType = net.isIP(ip); // returns 0 for invalid, 4 for IPv4, and 6 for IPv6
-    res.end('Hello, your ip address is ' + ip + ' and is of type IPv' + ipType + '\n');
+    res.end(
+        'Hello, your ip address is ' +
+            ip +
+            ' and is of type IPv' +
+            ipType +
+            '\n',
+    );
 });
 
 //create node.js http server and listen on port
 http.createServer(app).listen(3000);
 
 // test it locally from the command line
-// > curl -X GET localhost:3000 # Hello, your ip address is ::1 and is of type IPv6
+// > curl -X GET localhost:3000 # Hello, your ip address is ::1 and is of type IPv6