tut_proxy.html

---
layout: default-withsidebar
title: Using the Proxy API
copyright: opera-google-ccby
originalsource: http://developer.chrome.com/extensions/proxy.html
---


<h2 id="manifest">Manifest</h2>
<p>You must declare the "proxy" permission
in the <a href="manifest.html">extension manifest</a>
to use the proxy settings API.
For example:</p>
<pre data-filename="manifest.json">
{
  "name": "My extension",
  ...
  <b>"permissions": [
    "proxy"
  ]</b>,
  ...
}
</pre>

<h2 id="description">Objects and properties</h2>

<p>
Proxy settings are defined in a
<a href="https://developer.chrome.com/extensions/proxy#type-ProxyConfig">ProxyConfig</a> object. Depending on
Chrome's proxy settings, the settings may contain
<a href="https://developer.chrome.com/extensions/proxy#type-ProxyRules">ProxyRules</a> or a
  <a href="https://developer.chrome.com/extensions/proxy#type-PacScript">PacScript</a>.
</p>

<h3 id="proxy_modes">Proxy modes</h3>

<p>
A ProxyConfig object's <code>mode</code> attribute determines the overall
behavior of Chrome with regards to proxy usage. It can take the following
values:
<dl>
  <dt><code>direct</code></dt>
  <dd>In <code>direct</code> mode all connections are created directly, without
  any proxy involved. This mode allows no further parameters in the
  <code>ProxyConfig</code> object.</dd>

  <dt><code>auto_detect</code></dt>
  <dd>In <code>auto_detect</code> mode the proxy configuration is determined by
  a PAC script that can be downloaded at
  <a href="http://wpad/wpad.dat">http://wpad/wpad.dat</a>.
  This mode allows no further parameters in the <code>ProxyConfig</code>
  object.</dd>

  <dt><code>pac_script</code></dt>
  <dd>In <code>pac_script</code> mode the proxy configuration is determined by
  a PAC script that is either retrieved from the URL specified in the
  <a href="https://developer.chrome.com/extensions/proxy#type-PacScript">PacScript</a> object or
  taken literally from the <code>data</code> element specified in the
  <a href="https://developer.chrome.com/extensions/proxy#type-PacScript">PacScript</a> object.
  Besides this, this mode allows no further parameters in the
  <code>ProxyConfig</code> object.</dd>

  <dt><code>fixed_servers</code></dt>
  <dd>In <code>fixed_servers</code> mode the proxy configuration is codified in
  a <a href="https://developer.chrome.com/extensions/proxy#type-ProxyRules">ProxyRules</a>
  object. Its structure is described in <a href="#proxy_rules">Proxy rules</a>.
  Besides this, the <code>fixed_servers</code> mode allows no further parameters
  in the <code>ProxyConfig</code> object.</dd>

  <dt><code>system</code></dt>
  <dd>In <code>system</code> mode the proxy configuration is taken from the
  operating system. This mode allows no further parameters in the
  <code>ProxyConfig</code> object. Note that the <code>system</code> mode is
  different from setting no proxy configuration. In the latter case, Chrome
  falls back to the system settings only if no command-line options influence
  the proxy configuration.</dd>
</dl>
</p>

<h3 id="proxy_rules">Proxy rules</h3>

<p>
The <a href="https://developer.chrome.com/extensions/proxy#type-ProxyRules">ProxyRules</a> object can contain
either a <code>singleProxy</code> attribute or a subset of
<code>proxyForHttp</code>, <code>proxyForHttps</code>, <code>proxyForFtp</code>,
and <code>fallbackProxy</code>.
</p>

<p>
In the first case, HTTP, HTTPS and FTP traffic is proxied through the specified
proxy server. Other traffic is sent directly. In the latter case the behavior is
slightly more subtle: If a proxy server is configured for the HTTP, HTTPS or FTP
protocol, the respective traffic is proxied through the specified server. If no
such proxy server is specified or traffic uses a different protocol than HTTP,
HTTPS or FTP, the <code>fallbackProxy</code> is used. If no
<code>fallbackProxy</code> is specified, traffic is sent directly without a
proxy server.
</p>

<h3 id="proxy_server_objects">Proxy server objects</h3>

<p>
A proxy server is configured in a
<a href="https://developer.chrome.com/extensions/proxy#type-ProxyServer">ProxyServer</a> object. The connection
to the proxy server (defined by the <code>host</code> attribute) uses the
protocol defined in the <code>scheme</code> attribute. If no <code>scheme</code>
is specified, the proxy connection defaults to <code>http</code>.
</p>

<p>
If no <code>port</code> is defined in a
<a href="https://developer.chrome.com/extensions/proxy#type-ProxyServer">ProxyServer</a> object, the port is
derived from the scheme. The default ports are:
<table>
  <tr><th>Scheme</th><th>Port</th></tr>
  <tr><td>http</td><td>80</td></tr>
  <tr><td>https</td><td>443</td></tr>
  <tr><td>socks4</td><td>1080</td></tr>
  <tr><td>socks5</td><td>1080</td></tr>
</table>
</p>

<h3 id="bypass_list">Bypass list</h3>

<p>
Individual servers may be excluded from being proxied with the
<code>bypassList</code>. This list may contain the following entries:
<dl>
  <dt><code>[<em>&lt;scheme&gt;</em>://]<em>&lt;host-pattern&gt;</em>[:<em>&lt;port&gt;</em>]</code></dt>
  <dd>Match all hostnames that match the pattern <em>&lt;host-pattern&gt;</em>.
  A leading <code>"."</code> is interpreted as a <code>"*."</code>.<br>
  Examples: <code>"foobar.com", "*foobar.com", "*.foobar.com", "*foobar.com:99",
    "https://x.*.y.com:99"</code>.<br>
  <table>
    <tr>
      <th>Pattern
      <th>Matches
      <th>Does not match
    <tr>
      <td><code>".foobar.com"</code>
      <td><code>"www.foobar.com"</code>
      <td><code>"foobar.com"</code>
    <tr>
      <td><code>"*.foobar.com"</code>
      <td><code>"www.foobar.com"</code>
      <td><code>"foobar.com"</code>
    <tr>
      <td><code>"foobar.com"</code>
      <td><code>"foobar.com"</code>
      <td><code>"www.foobar.com"</code>
    <tr>
      <td><code>"*foobar.com"</code>
      <td><code>"foobar.com"</code>, <code>"www.foobar.com"</code>,
          <code>"foofoobar.com"</code>
      <td>
  </table>
  </dd>

  <dt><code>[<em>&lt;scheme&gt;</em>://]<em>&lt;ip-literal&gt;</em>[:<em>&lt;port&gt;</em>]</code></dt>
  <dd>Match URLs that are IP address literals.<br>
  Conceptually this is the similar to the first case, but with special cases
  to handle IP literal canonicalization. For example, matching
  on "[0:0:0::1]" is the same as matching on "[::1]" because
  the IPv6 canonicalization is done internally.<br>
  Examples: <code>"127.0.1", "[0:0::1]", "[::1]", "http://[::1]:99"</code></dd>

  <dt><code><em>&lt;ip-literal&gt;</em>/<em>&lt;prefix-length-in-bits&gt;</em></code></dt>
  <dd>Match any URL containing an IP literal within the given range. The IP
  range is specified using CIDR notation.<br>
  Examples: <code>"192.168.1.1/16", "fefe:13::abc/33"</code></dd>

  <dt><code>&lt;local&gt;</code></dt>
  <dd>Match local addresses. An address is local if the host is "127.0.0.1",
  "::1", or "localhost".<br>
  Example: <code>"&lt;local&gt;"</code></dd>
</dl>


<h2 id="overview-examples">Examples</h2>

<p>
The following code sets a SOCKS 5 proxy for HTTP connections to all servers but
foobar.com and uses direct connections for all other protocols. The settings
apply to regular and incognito windows, as incognito windows inherit settings
from regular windows. Please also consult the <a
  href="https://developer.chrome.com/extensions/types">Types API</a> documentation.
</p>

<pre>
var config = {
  mode: "fixed_servers",
  rules: {
    proxyForHttp: {
      scheme: "socks5",
      host: "1.2.3.4"
    },
    bypassList: ["foobar.com"]
  }
};
chrome.proxy.settings.set(
    {value: config, scope: 'regular'},
    function() {});
</pre>

<p>
The following code sets a custom PAC script.
</p>

<pre>
var config = {
  mode: "pac_script",
  pacScript: {
    data: "function FindProxyForURL(url, host) {\n" +
          "  if (host == 'foobar.com')\n" +
          "    return 'PROXY blackhole:80';\n" +
          "  return 'DIRECT';\n" +
          "}"
  }
};
chrome.proxy.settings.set(
    {value: config, scope: 'regular'},
    function() {});
</pre>

<p>
The next snippet queries the currently effective proxy settings. The effective
proxy settings can be determined by another extension or by a policy. See the <a
  href="https://developer.chrome.com/extensions/types">Types API</a> documentation for details.
</p>

<pre>
chrome.proxy.settings.get(
    {'incognito': false},
    function(config) {console.log(JSON.stringify(config));});
</pre>

<p>
Note that the <code>value</code> object passed to <code>set()</code> is not
identical to the <code>value</code> object passed to callback function of
<code>get()</code>. The latter will contain a
<code>rules.proxyForHttp.port</code> element.
</p>