init

README.md

+# user-agent-rewriter
+
+## What it does
+
+This extension uses the webRequest API to rewrite the browser's User Agent header, but only when visiting pages under "https://httpbin.org", for example: https://httpbin.org/user-agent
+
+It adds a browser action. The browser action has a popup that lets the user choose one of three browsers: Firefox 41, Chrome 41, and IE 11. When the user chooses a browser, the extension then rewrites the User Agent header so the real browser identifies itself as the chosen browser on the site https://httpbin.org/.
+
+## What it shows
+
+* how to intercept and modify HTTP requests
+* how to write a browser action with a popup
+* how to give the popup style and behavior using CSS and JS
+* how to send a message from a popup script to a background script

background.js

+
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+"use strict";
+
+var targetPage = "https://httpbin.org/*";
+var modifyTable = [];
+var started = "off";
+
+// If no table stored , use and store a default one
+if (!localStorage.getItem('modifyTable')) 
+	{
+	modifyTable = [
+		["add","test_header_name","test_header_value","on"],
+		];
+	localStorage.setItem("modifyTable",JSON.stringify(modifyTable));
+	}
+else 
+	{
+	modifyTable=JSON.parse(localStorage.getItem("modifyTable"));
+	}
+
+// If no target page stored , use a default one 
+if (!localStorage.getItem('targetPage')) localStorage.setItem('targetPage',targetPage);
+else targetPage = localStorage.getItem('targetPage');
+
+// If no started value stored , use a default one 
+if (!localStorage.getItem('started')) localStorage.setItem('started',started);
+else started = localStorage.getItem('started');
+
+if (started=="on") addListener();
+
+
+// listen for change in configuration or start/stop 
+browser.runtime.onMessage.addListener(notify);
+
+/**
+Rewrite the header
+**/
+function rewriteHeader(e) {
+  
+  window.console.info("IT Works");
+  for (var to_modify of modifyTable)
+	{
+		if (to_modify[3]=="on")
+			{
+			if (to_modify[0]=="add")  
+				{
+					console.log("add = " + to_modify[1]);
+					var new_header = {"name" :to_modify[1],"value":to_modify[2]};
+					e.requestHeaders.push(new_header);
+				}
+			else if (to_modify[0]=="modify")
+				{
+				for (var header of e.requestHeaders) 
+					{
+					if (header.name.toLowerCase() == to_modify[1].toLowerCase()) header.value = to_modify[2];
+					}
+				}
+			else if (to_modify[0]=="delete")
+				{
+				var index = -1;
+			
+				for (var i=0; i < e.requestHeaders.length; i++)
+					{
+				 	if (e.requestHeaders[i].name.toLowerCase() == to_modify[1].toLowerCase())  index=i;
+					}
+				if (index!=-1) 
+					{
+					e.requestHeaders.splice(index,1);	
+					}
+				}
+			}
+	}
+	
+  return {requestHeaders: e.requestHeaders};
+}
+
+
+
+
+function notify(message) 
+	{
+	if (message=="reload") 
+		{
+		modifyTable=JSON.parse(localStorage.getItem("modifyTable"));
+		targetPage = localStorage.getItem('targetPage');
+		if (started=="on")
+			{		
+			browser.webRequest.onBeforeSendHeaders.removeListener(rewriteHeader);
+			addListener();
+			}
+		}
+
+	else if (message=="off")
+		{
+		browser.webRequest.onBeforeSendHeaders.removeListener(rewriteHeader);
+		started="off";
+		}
+
+	else if (message=="on")
+		{
+		addListener();
+		started="on";
+		}
+  	}
+
+/*
+Add rewriteHeader as a listener to onBeforeSendHeaders,
+only for the target page.
+
+Make it "blocking" so we can modify the headers.
+*/
+function addListener()
+	{
+	browser.webRequest.onBeforeSendHeaders.addListener(rewriteHeader,
+                                          {urls: [targetPage]},
+                                          ["blocking", "requestHeaders"]);
+	}
+
+

icons/LICENSE

+The "person-32.png" "person-48.png" icons are taken from the Ionicons iconset (http://ionicons.com/), and are used here under the MIT license: http://opensource.org/licenses/MIT.

manifest.json

+{
+
+  "description": "Modify header nouvelle version ",
+  "manifest_version": 2,
+  "name": "modify-header-2",
+  "version": "0.1",
+  "homepage_url": "https://a_defenirnir",
+  "icons": {
+    "48": "icons/person-48.png"
+  },
+
+  "permissions": [
+    "activeTab","storage","webRequest", "webRequestBlocking", "https://httpbin.org/*" 
+  ],
+  
+  "background": {
+    "scripts": ["background.js"]
+  },
+
+  "browser_action": {
+    "default_icon": "icons/person-32.png",
+    "default_title": "Modify a header",
+    "default_popup": "popup/config.html"
+  }
+
+}

popup/config.html

+<!DOCTYPE html>
+
+<html>
+  <head>
+    <meta charset="utf-8">
+   
+  </head>
+
+<body>
+
+<table>
+<tr>
+<td width="530">
+  <h1> SIMPLE MODIFY HEADER   </h1> 
+
+  Url Pattern : <input id="targetPage"  type="text" value=""></input>
+</td>
+<td width="200">
+<img id="start_img" src="img/start.png" align="right" valign="center"> </img> 
+</td>
+</tr>
+</table>
+
+	<br>
+	<br>
+  <table id="config_tab" id="config"> 
+	<tr> 
+		<td> Action </td>		
+		<td> Header Name </td>
+		<td> Header Value </td>
+		<td> Status </td>
+	</tr>
+  </table>
+<center>
+<br>
+<input type="button" id="add_button" value="ADD NEW LINE" ></input>
+<input type="button" id="save_button" value="SAVE"></input>
+</center>
+ <script type="text/javascript" src="config.js"> </script>
+
+</body>
+
+</html>

popup/config.js

+ 
+
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+var line_number = 1;
+var started = "off";
+
+window.onload = function() {
+	var configTable = JSON.parse(localStorage.getItem("modifyTable"));	
+	for (var to_add of configTable) appendLine(to_add[0],to_add[1],to_add[2],to_add[3]);
+	document.getElementById('save_button').addEventListener('click',function (e) {save_data();});
+	document.getElementById('add_button').addEventListener('click',function (e) {appendLine("add","-","-","off");});
+	document.getElementById('start_img').addEventListener('click',function (e) {start_modify();});
+	document.getElementById('targetPage').value=localStorage.getItem("targetPage");
+	started = localStorage.getItem("started");
+	if (started=="on") document.getElementById("start_img").src = "img/stop.png";	
+} ;
+
+
+function appendLine(action,header_name,header_value,status) {
+
+var html = "<td><select id=\"select_action" + line_number + "\" disable=false><option value=\"add\">add</option><option value=\"modify\">modify</option><option value=\"delete\">delete</option></select></td>";
+html = html + "<td><input id=\"header_name"+ line_number +"\" value=\"" + header_name + "\"></input></td>";
+html = html + "<td><input id=\"header_value"+ line_number +"\" value=\"" + header_value + "\"></input></td>";
+html = html + "<td><select id=\"select_status" + line_number + "\"><option value=\"on\"> ON </option><option value=\"off\">OFF</option></select></td>";
+html = html + "<td><input type=\"button\" value=\"DELETE\" id=\"delete_button" + line_number + "\"></input> </td>";
+
+var newTR = document.createElement("tr");
+newTR.id="line" + line_number;
+newTR.innerHTML = html;
+document.getElementById("config_tab").appendChild(newTR);
+document.getElementById("select_action"+line_number).value = action;
+document.getElementById("select_status"+line_number).value = status;
+var line_number_to_delete = line_number;
+document.getElementById('delete_button'+line_number).addEventListener('click',function (e) {delete_line(line_number_to_delete)});
+line_number++;
+}
+
+
+
+
+function save_data () 
+	{
+	var tr_elements = document.querySelectorAll("#config_tab tr");
+	var to_save = [];
+	for (i=1;i<tr_elements.length;i++)  // ignore line 1 which is the table header
+		{
+		var line_to_save = [];
+		line_to_save.push(tr_elements[i].childNodes[0].childNodes[0].value); // select_action 
+		line_to_save.push(tr_elements[i].childNodes[1].childNodes[0].value); // header_name
+		line_to_save.push(tr_elements[i].childNodes[2].childNodes[0].value); // header_value
+		line_to_save.push(tr_elements[i].childNodes[3].childNodes[0].value); // status
+		to_save.push(line_to_save);
+		}
+	localStorage.setItem("modifyTable",JSON.stringify(to_save));
+	localStorage.setItem("targetPage",document.getElementById('targetPage').value);
+	browser.runtime.sendMessage("reload");
+	}
+
+
+
+function delete_line(line_number_to_delete)
+	{
+	if (line_number_to_delete != line_number) 
+			{
+			for (i=line_number_to_delete;i<line_number-1;i++)
+				{
+				var j = i+1;
+				console.log("i=" + i + ",j=" + j); 
+				document.getElementById("select_action"+i).value = document.getElementById("select_action"+j).value;
+				document.getElementById("header_name"+i).value = document.getElementById("header_name"+j).value;
+				document.getElementById("header_value"+i).value = document.getElementById("header_value"+j).value;
+				document.getElementById("select_status"+i).value = document.getElementById("select_status"+j).value;
+				}
+			}
+	var Node_to_delete = document.getElementById("line"+(line_number-1));
+    	Node_to_delete.parentNode.removeChild(Node_to_delete);
+	line_number--;
+	}
+
+
+function start_modify()
+	{
+	if (started=="off") 
+		{
+		localStorage.setItem("started","on");
+		browser.runtime.sendMessage("on");
+		started = "on";
+		document.getElementById("start_img").src = "img/stop.png";		
+		}
+	else 
+		{
+		localStorage.setItem("started","off");
+		browser.runtime.sendMessage("off");
+		started = "off";
+		document.getElementById("start_img").src = "img/start.png";
+		}
+
+	}