Navigation Timing plugin API

Note: The Navigation Timing plugin hasn't been tested. Your help in testing it is appreciated.

The Navigation Timing plugin collects metrics collected by modern user agents that support the W3C Navigation Timing specification. The Navigation Timing API is encapsulated within the BOOMR.plugins.NavigationTiming namespace.

Note that the Navigation Timing plugin isn't included by default in boomerang.js. See Howto #9 for details on how to include the plugin in your boomerang deployment.

Methods

init()

Called by the BOOMR.init() method to configure the Navigation Timing plugin. The Navigation Timing plugin doesn't require any configuration parameters, since it simply reads values out of the browser's window.performance object (if available) and adds them to the beacon query string.

Returns

a reference to the BOOMR.plugins.NavigationTiming object, so you can chain methods.

Note

If the user agent being examined doesn't implement the Navigation Timing spec, the plugin won't add any parameters to the beacon.

is_complete()

Called by BOOMR.sendBeacon() to determine if the Navigation Timing plugin has finished what it's doing or not.

Returns

true if the plugin has completed.
false if the plugin has not completed.

Beacon Parameters

The NavigationTiming plugin adds the following parameters to the beacon. Each maps onto a attribute from the browser's NavigationTiming API.

Beacon parameter	NavigationTiming attribute
`nt_red_cnt`	`window.performance.navigation.redirectCount`
`nt_nav_type`	`window.performance.navigation.type`
`nt_nav_st`	`window.performance.timing.navigationStart`
`nt_red_st`	`window.performance.timing.redirectStart`
`nt_red_end`	`window.performance.timing.redirectEnd`
`nt_fet_st`	`window.performance.timing.fetchStart`
`nt_dns_st`	`window.performance.timing.domainLookupStart`
`nt_dns_end`	`window.performance.timing.domainLookupEnd`
`nt_con_st`	`window.performance.timing.connectStart`
`nt_con_end`	`window.performance.timing.connectEnd`
`nt_req_st`	`window.performance.timing.requestStart`
`nt_res_st`	`window.performance.timing.responseStart`
`nt_res_end`	`window.performance.timing.responseEnd`
`nt_domloading`	`window.performance.timing.domLoading`
`nt_domint`	`window.performance.timing.domInteractive`
`nt_domcontloaded_st`	`window.performance.timing.domContentLoadedEventStart`
`nt_domcontloaded_end`	`window.performance.timing.domContentLoadedEventEnd`
`nt_domcomp`	`window.performance.timing.domComplete`
`nt_load_st`	`window.performance.timing.loadEventStart`
`nt_load_end`	`window.performance.timing.loadEventEnd`
`nt_unload_st`	`window.performance.timing.unloadEventStart`
`nt_unload_end`	`window.performance.timing.unloadEventEnd`
`nt_ssl_st`	[optional] `window.performance.secureConnectionStart`
`nt_spdy`	[optional] 1 if page was loaded over SPDY, 0 otherwise
`nt_first_paint`	[optional] The time when the first paint happened. On Internet Explorer, this is milliseconds since the epoch, while on Chrome this is seconds.microseconds since the epoch. If you detect a decimal point in this number, multiply it by 1000 to compare it to the other timers.

The latest code and docs is available on github.com/SOASTA/boomerang