PerformanceResourceTiming

Available on js

The PerformanceResourceTiming interface enables retrieval and analysis of detailed network timing data regarding the loading of an application's resources. An application can use the timing metrics to determine, for example, the length of time it takes to fetch a specific resource, such as an XMLHttpRequest, SVG, image, or script.

Documentation PerformanceResourceTiming by Mozilla Contributors, licensed under CC-BY-SA 2.5.

Variables

`read onlyconnectEnd:Float`

A DOMHighResTimeStamp immediately after the browser finishes establishing the connection to the server to retrieve the resource.

`read onlyconnectStart:Float`

A DOMHighResTimeStamp immediately before the browser starts to establish the connection to the server to retrieve the resource.

`read onlydecodedBodySize:Int`

A number that is the size (in octets) received from the fetch (HTTP or cache) of the message body, after removing any applied content-codings.

`read onlydomainLookupEnd:Float`

A DOMHighResTimeStamp representing the time immediately after the browser finishes the domain name lookup for the resource.

`read onlydomainLookupStart:Float`

A DOMHighResTimeStamp immediately before the browser starts the domain name lookup for the resource.

`read onlyencodedBodySize:Int`

A number representing the size (in octets) received from the fetch (HTTP or cache), of the payload body, before removing any applied content-codings.

`read onlyfetchStart:Float`

A DOMHighResTimeStamp immediately before the browser starts to fetch the resource.

`read onlyinitiatorType:String`

A DOMString representing the type of resource that initiated the performance entry, as specified in PerformanceResourceTiming.initiatorType.

`read onlynextHopProtocol:String`

A DOMString representing the network protocol used to fetch the resource, as identified by the ALPN Protocol ID (RFC7301).

`read onlyredirectEnd:Float`

A DOMHighResTimeStamp immediately after receiving the last byte of the response of the last redirect.

`read onlyredirectStart:Float`

A DOMHighResTimeStamp that represents the start time of the fetch which initiates the redirect.

`read onlyrequestStart:Float`

A DOMHighResTimeStamp immediately before the browser starts requesting the resource from the server.

`read onlyresponseEnd:Float`

A DOMHighResTimeStamp immediately after the browser receives the last byte of the resource or immediately before the transport connection is closed, whichever comes first.

`read onlyresponseStart:Float`

A DOMHighResTimeStamp immediately after the browser receives the first byte of the response from the server.

`read onlysecureConnectionStart:Float`

A DOMHighResTimeStamp immediately before the browser starts the handshake process to secure the current connection.

`read onlyserverTiming:Array<PerformanceServerTiming>`

An array of PerformanceServerTiming entries containing server timing metrics.

`read onlytransferSize:Int`

A number representing the size (in octets) of the fetched resource. The size includes the response header fields plus the response payload body.

`read onlyworkerStart:Float`

Returns a DOMHighResTimeStamp immediately before dispatching the FetchEvent if a Service Worker thread is already running, or immediately before starting the Service Worker thread if it is not already running. If the resource is not intercepted by a Service Worker the property will always return 0.

Methods

`toJSON():Dynamic`

Returns a DOMString that is the JSON representation of the PerformanceResourceTiming object.