PerformanceResourceTiming.redirectStart
The redirectStart
read-only property returns a
timestamp
representing the start time of the fetch
which that initiates the redirect.
If there are HTTP redirects when fetching the resource and if any of the redirects are not from the same origin as the current document, but the timing allow check algorithm passes for each redirected resource, this property returns the starting time of the fetch that initiates the redirect; otherwise, zero is returned.
Note: This feature is available in Web Workers
Syntax
resource.redirectStart;
Return value
A timestamp
representing the start time of the
fetch which initiates the redirect.
Example
In the following example, the value of the *Start
and *End
properties of all "resource
"
type
events are logged.
function print_PerformanceEntries() {
// Use getEntriesByType() to just get the "resource" events
var p = performance.getEntriesByType("resource");
for (var i=0; i < p.length; i++) {
print_start_and_end_properties(p[i]);
}
}
function print_start_and_end_properties(perfEntry) {
// Print timestamps of the PerformanceEntry *start and *end properties
properties = ["connectStart", "connectEnd",
"domainLookupStart", "domainLookupEnd",
"fetchStart",
"redirectStart", "redirectEnd",
"requestStart",
"responseStart", "responseEnd",
"secureConnectionStart"];
for (var i=0; i < properties.length; i++) {
// check each property
var supported = properties[i] in perfEntry;
if (supported) {
var value = perfEntry[properties[i]];
console.log("... " + properties[i] + " = " + value);
} else {
console.log("... " + properties[i] + " = NOT supported");
}
}
}
Specifications
Specification |
---|
Resource Timing Level 2 # dom-performanceresourcetiming-redirectstart |
Browser compatibility
BCD tables only load in the browser