session
Manage browser sessions, cookies, cache, proxy settings, etc.
Process: Main
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, or from the session module.
const {BrowserWindow} = require('electron')
let win = new BrowserWindow({width: 800, height: 600})
win.loadURL('http://github.com')
const ses = win.webContents.session
console.log(ses.getUserAgent())
Methods
The session module has the following methods:
session.fromPartition(partition[, options])
partitionStringoptionsObjectcacheBoolean - Whether to enable cache.
Returns Session - A session instance from partition string. When there is an existing
Session with the same partition, it will be returned; othewise a new
Session instance will be created with options.
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.
To create a Session with options, you have to ensure the Session with the
partition has never been used before. There is no way to change the options
of an existing Session object.
Properties
The session module has the following properties:
session.defaultSession
A Session object, the default session object of the app.
Class: Session
Get and set properties of a session.
Process: Main
You can create a Session object in the session module:
const {session} = require('electron')
const ses = session.fromPartition('persist:name')
console.log(ses.getUserAgent())
Instance Events
The following events are available on instances of Session:
Event: 'will-download'
eventEventitemDownloadItemwebContentsWebContents
Emitted when Electron is about to download item in webContents.
Calling event.preventDefault() will cancel the download and item will not be
available from next tick of the process.
const {session} = require('electron')
session.defaultSession.on('will-download', (event, item, webContents) => {
event.preventDefault()
require('request')(item.getURL(), (data) => {
require('fs').writeFileSync('/somewhere', data)
})
})
Instance Methods
The following methods are available on instances of Session:
ses.getCacheSize(callback)
callbackFunctionsizeInteger - Cache size used in bytes.
Returns the session's current cache size.
ses.clearCache(callback)
callbackFunction - Called when operation is done
Clears the session’s HTTP cache.
ses.clearStorageData([options, callback])
optionsObject (optional)originString - Should followwindow.location.origin’s representationscheme://host:port.storagesString[] - The types of storages to clear, can contain:appcache,cookies,filesystem,indexdb,local storage,shadercache,websql,serviceworkersquotasString[] - The types of quotas to clear, can contain:temporary,persistent,syncable.
callbackFunction (optional) - Called when operation is done.
Clears the data of web storages.
ses.flushStorageData()
Writes any unwritten DOMStorage data to disk.
ses.setProxy(config, callback)
configObjectpacScriptString - The URL associated with the PAC file.proxyRulesString - Rules indicating which proxies to use.proxyBypassRulesString - Rules indicating which URLs should bypass the proxy settings.
callbackFunction - Called when operation is done.
Sets the proxy settings.
When pacScript and proxyRules are provided together, the proxyRules
option is ignored and pacScript configuration is applied.
The proxyRules has to follow the rules below:
proxyRules = schemeProxies[";"<schemeProxies>]
schemeProxies = [<urlScheme>"="]<proxyURIList>
urlScheme = "http" | "https" | "ftp" | "socks"
proxyURIList = <proxyURL>[","<proxyURIList>]
proxyURL = [<proxyScheme>"://"]<proxyHost>[":"<proxyPort>]
For example:
http=foopy:80;ftp=foopy2- Use HTTP proxyfoopy:80forhttp://URLs, and HTTP proxyfoopy2:80forftp://URLs.foopy:80- Use HTTP proxyfoopy:80for all URLs.foopy:80,bar,direct://- Use HTTP proxyfoopy:80for all URLs, failing over tobariffoopy:80is unavailable, and after that using no proxy.socks4://foopy- Use SOCKS v4 proxyfoopy:1080for all URLs.http=foopy,socks5://bar.com- Use HTTP proxyfoopyfor http URLs, and fail over to the SOCKS5 proxybar.comiffoopyis unavailable.http=foopy,direct://- Use HTTP proxyfoopyfor http URLs, and use no proxy iffoopyis unavailable.http=foopy;socks=foopy2- Use HTTP proxyfoopyfor http URLs, and usesocks4://foopy2for all other URLs.
The proxyBypassRules is a comma separated list of rules described below:
[ URL_SCHEME "://" ] HOSTNAME_PATTERN [ ":" <port> ]Match all hostnames that match the pattern HOSTNAME_PATTERN.
Examples: "foobar.com", "foobar.com", ".foobar.com", "foobar.com:99", "https://x..y.com:99"
"." HOSTNAME_SUFFIX_PATTERN [ ":" PORT ]Match a particular domain suffix.
Examples: ".google.com", ".com", "http://.google.com"
[ SCHEME "://" ] IP_LITERAL [ ":" PORT ]Match URLs which are IP address literals.
Examples: "127.0.1", "[0:0::1]", "[::1]", "http://[::1]:99"
IP_LITERAL "/" PREFIX_LENGHT_IN_BITSMatch any URL that is to an IP literal that falls between the given range. IP range is specified using CIDR notation.
Examples: "192.168.1.1/16", "fefe:13::abc/33".
<local>Match local addresses. The meaning of
<local>is whether the host matches one of: "127.0.0.1", "::1", "localhost".
ses.resolveProxy(url, callback)
urlURLcallbackFunctionproxyObject
Resolves the proxy information for url. The callback will be called with
callback(proxy) when the request is performed.
ses.setDownloadPath(path)
pathString - The download location
Sets download saving directory. By default, the download directory will be the
Downloads under the respective app folder.
ses.enableNetworkEmulation(options)
optionsObjectofflineBoolean (optional) - Whether to emulate network outage. Defaults to false.latencyDouble (optional) - RTT in ms. Defaults to 0 which will disable latency throttling.downloadThroughputDouble (optional) - Download rate in Bps. Defaults to 0 which will disable download throttling.uploadThroughputDouble (optional) - Upload rate in Bps. Defaults to 0 which will disable upload throttling.
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)
procFunctionhostnameStringcertificateCertificatecallbackFunctionisTrustedBoolean - Determines if the certificate should be trusted
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.
const {BrowserWindow} = require('electron')
let win = new BrowserWindow()
win.webContents.session.setCertificateVerifyProc((hostname, cert, callback) => {
callback(hostname === 'github.com')
})
ses.setPermissionRequestHandler(handler)
handlerFunctionwebContentsObject - WebContents requesting the permission.permissionString - Enum of 'media', 'geolocation', 'notifications', 'midiSysex', 'pointerLock', 'fullscreen', 'openExternal'.callbackFunctionpermissionGrantedBoolean - Allow or deny the permission
Sets the handler which can be used to respond to permission requests for the session.
Calling callback(true) will allow the permission and callback(false) will reject it.
const {session} = require('electron')
session.fromPartition('some-partition').setPermissionRequestHandler((webContents, permission, callback) => {
if (webContents.getURL() === 'some-host' && permission === 'notifications') {
return callback(false) // denied.
}
callback(true)
})
ses.clearHostResolverCache([callback])
callbackFunction (optional) - Called when operation is done.
Clears the host resolver cache.
ses.allowNTLMCredentialsForDomains(domains)
domainsString - A comma-seperated list of servers for which integrated authentication is enabled.
Dynamically sets whether to always send credentials for HTTP NTLM or Negotiate authentication.
const {session} = require('electron')
// consider any url ending with `example.com`, `foobar.com`, `baz`
// for integrated authentication.
session.defaultSession.allowNTLMCredentialsForDomains('*example.com, *foobar.com, *baz')
// consider all urls for integrated authentication.
session.defaultSession.allowNTLMCredentialsForDomains('*')
ses.setUserAgent(userAgent[, acceptLanguages])
userAgentStringacceptLanguagesString (optional)
Overrides the userAgent and acceptLanguages for this session.
The acceptLanguages must a comma separated ordered list of language codes, for
example "en-US,fr,de,ko,zh-CN,ja".
This doesn't affect existing WebContents, and each WebContents can use
webContents.setUserAgent to override the session-wide user agent.
ses.getUserAgent()
Returns String - The user agent for this session.
ses.getBlobData(identifier, callback)
identifierString - Valid UUID.callbackFunctionresultBuffer - Blob data.
Returns Blob - The blob data associated with the identifier.
Instance Properties
The following properties are available on instances of Session:
ses.cookies
A Cookies object for this session.
ses.webRequest
A WebRequest object for this session.
ses.protocol
A Protocol object (an instance of protocol module) for this session.
const {app, session} = require('electron')
const path = require('path')
app.on('ready', function () {
const protocol = session.fromPartition('some-partition').protocol
protocol.registerFileProtocol('atom', function (request, callback) {
var url = request.url.substr(7)
callback({path: path.normalize(`${__dirname}/${url}`)})
}, function (error) {
if (error) console.error('Failed to register protocol')
})
})
Class: Cookies
Query and modify a session's cookies.
Process: Main
Instances of the Cookies class are accessed by using cookies property of
a Session.
For example:
const {session} = require('electron')
// Query all cookies.
session.defaultSession.cookies.get({}, (error, cookies) => {
console.log(error, cookies)
})
// Query all cookies associated with a specific url.
session.defaultSession.cookies.get({url: 'http://www.github.com'}, (error, cookies) => {
console.log(error, cookies)
})
// Set a cookie with the given cookie data;
// may overwrite equivalent cookies if they exist.
const cookie = {url: 'http://www.github.com', name: 'dummy_name', value: 'dummy'}
session.defaultSession.cookies.set(cookie, (error) => {
if (error) console.error(error)
})
Instance Events
The following events are available on instances of Cookies:
Event: 'changed'
eventEventcookieCookie - The cookie that was changedcauseString - The cause of the change with one of the following values:explicit- The cookie was changed directly by a consumer's action.overwrite- The cookie was automatically removed due to an insert operation that overwrote it.expired- The cookie was automatically removed as it expired.evicted- The cookie was automatically evicted during garbage collection.expired-overwrite- The cookie was overwritten with an already-expired expiration date.
removedBoolean -trueif the cookie was removed,falseotherwise.
Emitted when a cookie is changed because it was added, edited, removed, or expired.
Instance Methods
The following methods are available on instances of Cookies:
cookies.get(filter, callback)
filterObjecturlString (optional) - Retrieves cookies which are associated withurl. Empty implies retrieving cookies of all urls.nameString (optional) - Filters cookies by name.domainString (optional) - Retrieves cookies whose domains match or are subdomains ofdomainspathString (optional) - Retrieves cookies whose path matchespath.secureBoolean (optional) - Filters cookies by their Secure property.sessionBoolean (optional) - Filters out session or persistent cookies.
callbackFunctionerrorErrorcookiesCookies[]
Sends a request to get all cookies matching details, callback will be called
with callback(error, cookies) on complete.
cookies is an Array of cookie objects.
cookies.set(details, callback)
detailsObjecturlString - The url to associate the cookie with.nameString - The name of the cookie. Empty by default if omitted.valueString - The value of the cookie. Empty by default if omitted.domainString - The domain of the cookie. Empty by default if omitted.pathString - The path of the cookie. Empty by default if omitted.secureBoolean - Whether the cookie should be marked as Secure. Defaults to false.httpOnlyBoolean - Whether the cookie should be marked as HTTP only. Defaults to false.expirationDateDouble - The expiration date of the cookie as the number of seconds since the UNIX epoch. If omitted then the cookie becomes a session cookie and will not be retained between sessions.
callbackFunctionerrorError
Sets a cookie with details, callback will be called with callback(error)
on complete.
cookies.remove(url, name, callback)
urlString - The URL associated with the cookie.nameString - The name of cookie to remove.callbackFunction
Removes the cookies matching url and name, callback will called with
callback() on complete.
Class: WebRequest
Intercept and modify the contents of a request at various stages of its lifetime.
Process: Main
Instances of the WebRequest class are accessed by using the webRequest
property of a Session.
The methods of WebRequest accept an optional filter and a listener. The
listener will be called with listener(details) when the API's event has
happened. The details object describes the request. Passing null
as listener will unsubscribe from the event.
The filter object has a urls property which is an Array of URL
patterns that will be used to filter out the requests that do not match the URL
patterns. If the filter is omitted then all requests will be matched.
For certain events the listener is passed with a callback, which should be
called with a response object when listener has done its work.
An example of adding User-Agent header for requests:
const {session} = require('electron')
// Modify the user agent for all requests to the following urls.
const filter = {
urls: ['https://*.github.com/*', '*://electron.github.io']
}
session.defaultSession.webRequest.onBeforeSendHeaders(filter, (details, callback) => {
details.requestHeaders['User-Agent'] = 'MyAgent'
callback({cancel: false, requestHeaders: details.requestHeaders})
})
Instance Methods
The following methods are available on instances of WebRequest:
webRequest.onBeforeRequest([filter, ]listener)
filterObjectlistenerFunctiondetailsObjectidIntegerurlStringmethodStringresourceTypeStringtimestampDoubleuploadDataUploadData[]
callbackFunctionresponseObjectcancelBoolean (optional)redirectURLString (optional) - The original request is prevented from being sent or completed and is instead redirected to the given URL.
The listener will be called with listener(details, callback) when a request
is about to occur.
The uploadData is an array of UploadData objects.
The callback has to be called with an response object.
webRequest.onBeforeSendHeaders([filter, ]listener)
filterObjectlistenerFunction
The listener will be called with listener(details, callback) 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.
detailsObjectidIntegerurlStringmethodStringresourceTypeStringtimestampDoublerequestHeadersObject
callbackFunctionresponseObjectcancelBoolean (optional)requestHeadersObject (optional) - When provided, request will be made with these headers.
The callback has to be called with an response object.
webRequest.onSendHeaders([filter, ]listener)
filterObjectlistenerFunctiondetailsObjectidIntegerurlStringmethodStringresourceTypeStringtimestampDoublerequestHeadersObject
The listener will be called with listener(details) 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.
webRequest.onHeadersReceived([filter, ]listener)
filterObjectlistenerFunction
The listener will be called with listener(details, callback) when HTTP
response headers of a request have been received.
detailsObjectidStringurlStringmethodStringresourceTypeStringtimestampDoublestatusLineStringstatusCodeIntegerresponseHeadersObject
callbackFunctionresponseObjectcancelBooleanresponseHeadersObject (optional) - When provided, the server is assumed to have responded with these headers.statusLineString (optional) - Should be provided when overridingresponseHeadersto change header status otherwise original response header's status will be used.
The callback has to be called with an response object.
webRequest.onResponseStarted([filter, ]listener)
filterObjectlistenerFunctiondetailsObjectidIntegerurlStringmethodStringresourceTypeStringtimestampDoubleresponseHeadersObjectfromCacheBoolean - Indicates whether the response was fetched from disk cache.statusCodeIntegerstatusLineString
The listener will be called with listener(details) when first byte of the
response body is received. For HTTP requests, this means that the status line
and response headers are available.
webRequest.onBeforeRedirect([filter, ]listener)
filterObjectlistenerFunctiondetailsObjectidStringurlStringmethodStringresourceTypeStringtimestampDoubleredirectURLStringstatusCodeIntegeripString (optional) - The server IP address that the request was actually sent to.fromCacheBooleanresponseHeadersObject
The listener will be called with listener(details) when a server initiated
redirect is about to occur.
webRequest.onCompleted([filter, ]listener)
filterObjectlistenerFunctiondetailsObjectidIntegerurlStringmethodStringresourceTypeStringtimestampDoubleresponseHeadersObjectfromCacheBooleanstatusCodeIntegerstatusLineString
The listener will be called with listener(details) when a request is
completed.
webRequest.onErrorOccurred([filter, ]listener)
filterObjectlistenerFunctiondetailsObjectidIntegerurlStringmethodStringresourceTypeStringtimestampDoublefromCacheBooleanerrorString - The error description.
The listener will be called with listener(details) when an error occurs.