Add new fields and getter steps for static routing resource timing (#1769)

This commit adds necessary fields and steps to realize timing info for the ServiceWorker static routing API discussed in w3c/resource-timing#389.

Author: quasi-mod

docs/index.bs

@@ -241,7 +241,7 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
   <section>
     <h3 id="service-worker-timing">Service Worker Timing</h3>
 
-    Service workers mark certain points in time that are later exposed by the <a interface lt="PerformanceNavigationTiming">navigation timing</a> API.
+    Service workers mark certain points in time that are later exposed by the <a interface lt="PerformanceNavigationTiming">navigation timing</a> API and <a interface lt="PerformanceResourceTiming">resource timing</a> API.
 
     A <dfn export>service worker timing info</dfn> is a [=/struct=]. It has the following [=struct/items=]:
 
@@ -250,6 +250,14 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
         :: A {{DOMHighResTimeStamp}}, initially 0.
         : <dfn export>fetch event dispatch time</dfn>
         :: A {{DOMHighResTimeStamp}}, initially 0.
+        : <dfn export>worker router evaluation start</dfn>
+        :: A {{DOMHighResTimeStamp}}, initially 0.
+        : <dfn export>worker cache lookup start</dfn>
+        :: A {{DOMHighResTimeStamp}}, initially 0.
+        : <dfn export>worker matched router source</dfn>
+        :: A {{DOMString}}, initially an empty string.
+        : <dfn export>worker final router source</dfn>
+        :: A {{DOMString}}, initially an empty string.
     </section>
   </section>
 
@@ -1092,7 +1100,7 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
 
     A {{ServiceWorkerGlobalScope}} object has an associated <dfn for="ServiceWorkerGlobalScope">force bypass cache for import scripts flag</dfn>. It is initially unset.
 
-    A {{ServiceWorkerGlobalScope}} object has an associated <dfn for="ServiceWorkerGlobalScope">race response map</dfn> which is an [=ordered map=] where the [=map/keys=] are [=/requests=] and the [=map/values=] are [=race response=].
+    A {{ServiceWorkerGlobalScope}} object has an associated <dfn for="ServiceWorkerGlobalScope">race response map</dfn> which is an [=ordered map=] where the [=map/keys=] are [=/requests=] and the [=map/values=] are [=/race response=].
 
     A <dfn id="dfn-race-response">race response</dfn> is a [=struct=] used to contain the network response when {{RouterSourceEnum/"race-network-and-fetch-handler"}} performs. It has a <dfn for="race response">value</dfn>, which is a [=/response=], "<code>pending</code>", or null.
 
@@ -2557,6 +2565,12 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
 
         Note: Keep this definition in sync with [=fetch a classic worker-imported script=].
 
+  A <dfn id="dfn-race-result">race result</dfn> is a [=tuple=] of a [=race result/routed response=] and [=race result/used route=].
+
+  A [=/race result=] has an associated <dfn export for="race result">routed response</dfn> (a [=/response=]).
+
+  A [=/race result=] has an associated <dfn export for="race result">used route</dfn> (a {{RouterSourceEnum}}).
+
   <section algorithm>
     <h3 id="create-job-algorithm"><dfn>Create Job</dfn></h3>
 
@@ -3215,13 +3229,16 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
           * |request| is a [=non-subresource request=].
           * |request| is a [=subresource request=] and |registration| is [=stale=].
       1. If |activeWorker|'s [=service worker/list of router rules=] [=list/is not empty=]:
+          1. Set |timingInfo|’s [=service worker timing info/worker router evaluation start=] to the [=coarsened shared current time=] given |useHighResPerformanceTimers|.
           1. Let |source| be the result of running the [=Get Router Source=] algorithm with |registration|'s <a>active worker</a> and |request|.
           1. If |source| is non-null, then:
+              1. Set |timingInfo|'s [=service worker timing info/worker matched router source=] be set to |source|, and [=service worker timing info/worker final router source=] be set to {{RouterSourceEnum/"network"}}.
               1. If |source| is {{RouterSourceEnum/"network"}}:
                   1. If |shouldSoftUpdate| is true, then [=in parallel=] run the [=Soft Update=] algorithm with |registration|.
                   1. Return null.
               1. Else if |source| is {{RouterSourceEnum/"cache"}}, or |source|["{{RouterSourceDict/cacheName}}"] [=map/exists=], then:
                   1. If |shouldSoftUpdate| is true, then [=in parallel=] run the [=Soft Update=] algorithm with |registration|.
+                  1. Set |timingInfo|’s [=service worker timing info/worker cache lookup start=] to the [=coarsened shared current time=] given |useHighResPerformanceTimers|.
                   1. [=map/For each=] |cacheName| &#x2192; |cache| of the |registration|'s [=service worker registration/storage key=]'s [=name to cache map=].
                       1. If |source|["{{RouterSourceDict/cacheName}}"] [=map/exists=] and |source|["{{RouterSourceDict/cacheName}}"] [=string/is=] not |cacheName|, [=continue=].
                       1. Let |requestResponses| be the result of running [=Query Cache=] with |request|, a new {{CacheQueryOptions}}, and |cache|.
@@ -3237,18 +3254,20 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
                           Note: This only creates a ServiceWorkerGlobalScope because CORS checks require that. It is not expected that implementations will actually create a ServiceWorkerGlobalScope here.
 
                           1. If |response|'s [=response/type=] is "`opaque`", and [=cross-origin resource policy check=] with |globalObject|'s [=environment settings object/origin=], |globalObject|, "", and |response|'s [=filtered response/internal response=] returns <b>blocked</b>, then return null.
+                          1. Set |timingInfo|'s [=service worker timing info/worker final router source=] be set to {{RouterSourceEnum/"cache"}}.
                           1. Return |response|.
                   1. Return null.
               1. Else if |source| is {{RouterSourceEnum/"race-network-and-fetch-handler"}}, and |request|'s [=request/method=] is \`<code>GET</code>\` then:
                   1. If |shouldSoftUpdate| is true, then [=in parallel=] run the [=Soft Update=] algorithm with |registration|.
-                  1. Let |queue| be an empty [=queue=] of [=/response=].
+                  1. Let |queue| be an empty [=queue=] of [=race result=].
                   1. Let |raceFetchController| be null.
                   1. Let |raceResponse| be a [=race response=] whose [=race response/value=] is "<code>pending</code>".
                   1. Run the following substeps [=in parallel=], but [=abort when=] |fetchController|'s [=fetch controller/state=] is "<code>terminated</code>" or "<code>aborted</code>":
                       1. Set |raceFetchController| to the result of calling [=fetch=] given |request|, with [=fetch/processResponse=] set to the following steps given a [=/response=] |raceNetworkRequestResponse|:
                           1. If |raceNetworkRequestResponse|'s [=response/status=] is [=ok status=], then:
                               1. Set |raceResponse|'s [=race response/value=] to |raceNetworkRequestResponse|.
-                              1. [=queue/Enqueue=] |raceNetworkRequestResponse| to |queue|.
+                              1. Let |raceNetworkResult| be a [=race result=] whose [=race result/routed response=] is |raceNetworkRequestResponse| and [=race result/used route=] is {{RouterSourceEnum/"network"}}.
+                              1. [=queue/Enqueue=] |raceNetworkResult| to |queue|.
                           1. Otherwise, set |raceResponse|'s [=race response/value=] to a [=network error=].
                   1. [=If aborted=] and |raceFetchController| is not null, then:
                       1. [=fetch controller/Abort=] |raceFetchController|.
@@ -3257,9 +3276,12 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
                   1. Run the following substeps [=in parallel=]:
                       1. Let |fetchHandlerResponse| be the result of [=Create Fetch Event and Dispatch=] with |request|, |registration|, |useHighResPerformanceTimers|, |timingInfo|, |workerRealm|, |reservedClient|, |preloadResponse|, and |raceResponse|.
                       1. If |fetchHandlerResponse| is not null and not a [=network error=], and |raceFetchController| is not null, [=fetch controller/abort=] |raceFetchController|.
-                      1. [=queue/Enqueue=] |fetchHandlerResponse| to |queue|.
+                      1. Let |raceFetchHandlerResult| be a [=race result=] whose [=race result/routed response=] is |fetchHandlerResponse| and [=race result/used route=] is {{RouterSourceEnum/"fetch-event"}}.
+                      1. [=queue/Enqueue=] |raceFetchHandlerResult| to |queue|.
                   1. Wait until |queue| is not empty.
-                  1. Return the result of [=dequeue=] |queue|.
+                  1. Let |result| be the result of [=dequeue=] |queue|.
+                  1. Set |timingInfo|'s [=service worker timing info/worker final router source=] be set to |result|'s [=race result/used route=].
+                  1. Return |result|'s [=/race response=].
               1. Assert: |source| is "{{RouterSourceEnum/fetch-event}}"
       1. If |request| is a [=navigation request=], |registration|'s [=navigation preload enabled flag=] is set, |request|'s [=request/method=] is \`<code>GET</code>\`, |registration|'s [=active worker=]'s [=set of event types to handle=] [=set/contains=] <code>fetch</code>, and |registration|'s [=active worker=]'s [=all fetch listeners are empty flag=] is not set then:
 
@@ -3283,7 +3305,10 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
               1. Let |deserializedError| be the result of [=deserialize a serialized abort reason=] given null and |workerRealm|.
               1. [=fetch controller/Abort=] |preloadFetchController| with |deserializedError|.
       1. Else, resolve |preloadResponse| with undefined.
-      1. Return the result of [=Create Fetch Event and Dispatch=] with |request|, |registration|, |useHighResPerformanceTimers|, |timingInfo|, |workerRealm|, |reservedClient|, |preloadResponse|, and null.
+      1. Let |fetchResult| be the result of [=Create Fetch Event and Dispatch=] with |request|, |registration|, |useHighResPerformanceTimers|, |timingInfo|, |workerRealm|, |reservedClient|, |preloadResponse|, and null.
+      1. If |fetchResult| is not null and |timingInfo|'s [=service worker timing info/worker final router source=] is set to {{RouterSourceEnum/"network"}}:
+        1. Set |timingInfo|'s [=service worker timing info/worker final router source=] to {{RouterSourceEnum/"fetch-event"}}.
+      1. Return |fetchResult|.
   </section>
 
   <section algorithm>