electron/docs/api/session.md

session

The session module can be used to create new Session objects.

You can also access the session of existing pages by using the session property of webContents which is a property of BrowserWindow.

const BrowserWindow = require('electron').BrowserWindow;

var win = new BrowserWindow({ width: 800, height: 600 });
win.loadURL("http://github.com");

var ses = win.webContents.session

Methods

The session module has the following methods:

session.fromPartition(partition)

• partition String

Returns a new Session instance from partition string.

If partition starts with persist:, the page will use a persistent session available to all pages in the app with the same partition. if there is no persist: prefix, the page will use an in-memory session. If the partition is empty then default session of the app will be returned.

Properties

The session module has the following properties:

session.defaultSession

Returns the default session object of the app.

Class: Session

You can create a Session object in the session module:

const session = require('electron').session;

var ses = session.fromPartition('persist:name');

Instance Events

The following events are available on instances of Session:

Event: 'will-download'

• event Event
• item DownloadItem
• webContents WebContents

Emitted when Electron is about to download item in webContents.

Calling event.preventDefault() will cancel the download.

session.on('will-download', function(event, item, webContents) {
  event.preventDefault();
  require('request')(item.getURL(), function(data) {
    require('fs').writeFileSync('/somewhere', data);
  });
});

Instance Methods

The following methods are available on instances of Session:

ses.cookies

The cookies gives you ability to query and modify cookies. For example:

const BrowserWindow = require('electron').BrowserWindow;

var win = new BrowserWindow({ width: 800, height: 600 });

win.loadURL('https://github.com');

win.webContents.on('did-finish-load', function() {
  // Query all cookies.
  win.webContents.session.cookies.get({}, function(error, cookies) {
    if (error) throw error;
    console.log(cookies);
  });

  // Query all cookies associated with a specific url.
  win.webContents.session.cookies.get({ url : "http://www.github.com" },
      function(error, cookies) {
        if (error) throw error;
        console.log(cookies);
  });

  // Set a cookie with the given cookie data;
  // may overwrite equivalent cookies if they exist.
  win.webContents.session.cookies.set(
    { url : "http://www.github.com", name : "dummy_name", value : "dummy"},
    function(error, cookies) {
      if (error) throw error;
      console.log(cookies);
  });
});

ses.cookies.get(details, callback)

details Object, properties:

• url String - Retrieves cookies which are associated with url. Empty implies retrieving cookies of all urls.
• name String - Filters cookies by name
• domain String - Retrieves cookies whose domains match or are subdomains of domains
• path String - Retrieves cookies whose path matches path
• secure Boolean - Filters cookies by their Secure property
• session Boolean - Filters out session or persistent cookies.
• callback Function - function(error, cookies)
• error Error
• cookies Array - array of cookie objects, properties:
  • name String - The name of the cookie.
  • value String - The value of the cookie.
  • domain String - The domain of the cookie.
  • host_only String - Whether the cookie is a host-only cookie.
  • path String - The path of the cookie.
  • secure Boolean - Whether the cookie is marked as Secure (typically HTTPS).
  • http_only Boolean - Whether the cookie is marked as HttpOnly.
  • session Boolean - Whether the cookie is a session cookie or a persistent cookie with an expiration date.
  • expirationDate Double - (Option) The expiration date of the cookie as the number of seconds since the UNIX epoch. Not provided for session cookies.

ses.cookies.set(details, callback)

details Object, properties:

• url String - Retrieves cookies which are associated with url

• name String - The name of the cookie. Empty by default if omitted.

• value String - The value of the cookie. Empty by default if omitted.

• domain String - The domain of the cookie. Empty by default if omitted.

• path String - The path of the cookie. Empty by default if omitted.

• secure Boolean - Whether the cookie should be marked as Secure. Defaults to false.

• session Boolean - Whether the cookie should be marked as HttpOnly. Defaults to false.

• expirationDate Double - The expiration date of the cookie as the number of seconds since the UNIX epoch. If omitted, the cookie becomes a session cookie.

• callback Function - function(error)

  • error Error

ses.cookies.remove(details, callback)

• details Object
  • url String - The URL associated with the cookie
  • name String - The name of cookie to remove
• callback Function - function(error)
  • error Error

ses.clearCache(callback)

• callback Function - Called when operation is done

Clears the session’s HTTP cache.

ses.clearStorageData([options, ]callback)

• options Object (optional)
  • origin String - Should follow window.location.origin’s representation scheme://host:port.
  • storages Array - The types of storages to clear, can contain: appcache, cookies, filesystem, indexdb, local storage, shadercache, websql, serviceworkers
  • quotas Array - The types of quotas to clear, can contain: temporary, persistent, syncable.
• callback Function - Called when operation is done.

Clears the data of web storages.

ses.setProxy(config, callback)

• config String
• callback Function - Called when operation is done.

If config is a PAC url, it is used directly otherwise config is parsed based on the following rules indicating which proxies to use for the session.

config = scheme-proxies[";"<scheme-proxies>]
scheme-proxies = [<url-scheme>"="]<proxy-uri-list>
url-scheme = "http" | "https" | "ftp" | "socks"
proxy-uri-list = <proxy-uri>[","<proxy-uri-list>]
proxy-uri = [<proxy-scheme>"://"]<proxy-host>[":"<proxy-port>]

  For example:
       "http=foopy:80;ftp=foopy2"  -- use HTTP proxy "foopy:80" for http://
                                      URLs, and HTTP proxy "foopy2:80" for
                                      ftp:// URLs.
       "foopy:80"                  -- use HTTP proxy "foopy:80" for all URLs.
       "foopy:80,bar,direct://"    -- use HTTP proxy "foopy:80" for all URLs,
                                      failing over to "bar" if "foopy:80" is
                                      unavailable, and after that using no
                                      proxy.
       "socks4://foopy"            -- use SOCKS v4 proxy "foopy:1080" for all
                                      URLs.
       "http=foopy,socks5://bar.com -- use HTTP proxy "foopy" for http URLs,
                                      and fail over to the SOCKS5 proxy
                                      "bar.com" if "foopy" is unavailable.
       "http=foopy,direct://       -- use HTTP proxy "foopy" for http URLs,
                                      and use no proxy if "foopy" is
                                      unavailable.
       "http=foopy;socks=foopy2   --  use HTTP proxy "foopy" for http URLs,
                                      and use socks4://foopy2 for all other
                                      URLs.

ses.resolveProxy(url, callback)

• url URL
• callback Function

Resolves the proxy information for url. The callback will be called with callback(proxy) when the request is performed.

ses.setDownloadPath(path)

• path String - The download location

Sets download saving directory. By default, the download directory will be the Downloads under the respective app folder.

ses.enableNetworkEmulation(options)

• options Object
  • offline Boolean - Whether to emulate network outage.
  • latency Double - RTT in ms
  • downloadThroughput Double - Download rate in Bps
  • uploadThroughput Double - Upload rate in Bps

Emulates network with the given configuration for the session.

// To emulate a GPRS connection with 50kbps throughput and 500 ms latency.
window.webContents.session.enableNetworkEmulation({
    latency: 500,
    downloadThroughput: 6400,
    uploadThroughput: 6400
});

// To emulate a network outage.
window.webContents.session.enableNetworkEmulation({offline: true});

ses.disableNetworkEmulation()

Disables any network emulation already active for the session. Resets to the original network configuration.

ses.setCertificateVerifyProc(proc)

• proc Function

Sets the certificate verify proc for session, the proc will be called with proc(hostname, certificate, callback) whenever a server certificate verification is requested. Calling callback(true) accepts the certificate, calling callback(false) rejects it.

Calling setCertificateVerifyProc(null) will revert back to default certificate verify proc.

myWindow.webContents.session.setCertificateVerifyProc(function(hostname, cert, callback) {
  if (hostname == 'github.com')
    callback(true);
  else
    callback(false);
});

ses.webRequest

The webRequest api allows to intercept and modify contents of a request at various stages of its lifetime.

// Modify the user agent for all requests to the following urls.

var filter = {
  urls: ["https://*.github.com/*", "*://electron.github.io"]
}

myWindow.webContents.session.webRequest.onBeforeSendHeaders(filter, function(details) {
  details.requestHeaders['User-Agent'] = "MyAgent";
  return {cancel: false, requestHeaders: details.requestHeaders};
})

ses.webRequest.onBeforeRequest([filter,] listener)

• filter Object
  • urls Array - A list of URLs or URL patterns. Request that cannot match any of the URLs will be filtered out.
• listener Function
  • details Object
    • id String - Request id.
    • url String
    • method String
    • resourceType String
    • timestamp Double
• blockingResponse Object
  • cancel Boolean - Whether to continue or block the request.
  • redirectURL String optional - The original request is prevented from being sent or completed, and is instead redirected to the given URL.

Fired when a request is about to occur. Should return a blockingResponse.

ses.webRequest.onBeforeSendHeaders([filter,] listener)

• filter Object
  • urls Array - A list of URLs or URL patterns. Request that cannot match any of the URLs will be filtered out.
• listener Function
  • details Object
    • id String - Request id.
    • url String
    • method String
    • resourceType String
    • timestamp Double
    • requestHeaders Object
• blockingResponse Object
  • cancel Boolean - Whether to continue or block the request.
  • requestHeaders Object optional - When provided, request will be made with these headers.

Fired before sending an HTTP request, once the request headers are available. This may occur after a TCP connection is made to the server, but before any http data is sent. Should return a blockingResponse.

ses.webRequest.onSendHeaders([filter,] listener)

• filter Object
  • urls Array - A list of URLs or URL patterns. Request that cannot match any of the URLs will be filtered out.
• listener Function
  • details Object
    • id String - Request id.
    • url String
    • method String
    • resourceType String
    • timestamp Double
    • requestHeaders Object

Fired just before a request is going to be sent to the server, modifications of previous onBeforeSendHeaders response are visible by the time this listener is fired.

ses.webRequest.onHeadersReceived([filter,] listener)

• filter Object
  • urls Array - A list of URLs or URL patterns. Request that cannot match any of the URLs will be filtered out.
• listener Function
  • details Object
    • id String - Request id.
    • url String
    • method String
    • resourceType String
    • timestamp Double
    • statusLine String
    • statusCode Integer
    • responseHeaders Object
• blockingResponse Object
  • cancel Boolean - Whether to continue or block the request.
  • responseHeaders Object optional - When provided, the server is assumed to have responded with these headers.

Fired when HTTP response headers of a request have been received. Should return a blockingResponse.

ses.webRequest.onResponseStarted([filter,] listener)

• filter Object
  • urls Array - A list of URLs or URL patterns. Request that cannot match any of the URLs will be filtered out.
• listener Function
  • details Object
    • id String - Request id.
    • url String
    • method String
    • resourceType String
    • timestamp Double
    • responseHeaders Object
    • fromCache Boolean
    • statusCode Integer
    • statusLine String

Fired when first byte of the response body is received. For HTTP requests, this means that the status line and response headers are available.

ses.webRequest.onBeforeRedirect([filter,] listener)

• filter Object
  • urls Array - A list of URLs or URL patterns. Request that cannot match any of the URLs will be filtered out.
• listener Function
  • details Object
    • id String - Request id.
    • url String
    • method String
    • resourceType String
    • timestamp Double
    • redirectURL String
    • statusCode Integer
    • ip String - The server IP address that the request was actually sent to.
    • fromCache Boolean
    • responseHeaders Object

Fired when a server initiated redirect is about to occur.

ses.webRequest.onCompleted([filter,] listener)

• filter Object
  • urls Array - A list of URLs or URL patterns. Request that cannot match any of the URLs will be filtered out.
• listener Function
  • details Object
    • id String - Request id.
    • url String
    • method String
    • resourceType String
    • timestamp Double
    • responseHeaders Object
    • fromCache Boolean - Indicates whether the response was fetched from disk cache.
    • statusCode Integer
    • statusLine String

Fired when a request is completed.

ses.webRequest.onErrorOccurred([filter,] listener)

• filter Object
  • urls Array - A list of URLs or URL patterns. Request that cannot match any of the URLs will be filtered out.
• listener Function
  • details Object
    • id String - Request id.
    • url String
    • method String
    • resourceType String
    • timestamp Double
    • fromCache Boolean - Indicates whether the response was fetched from disk cache.
    • error String - The error description.

Fired when an error occurs.