From fcabe9cf1fcd57e1d5b927603b6188f58fa19f62 Mon Sep 17 00:00:00 2001 From: Jungkee Song Date: Mon, 5 Mar 2018 21:58:35 +0900 Subject: [PATCH] Improve service worker script caching and update This change includes/considers the following: - Include imported scripts to byte-check (for classic scripts). - Compare responses' body instead of source text as per https://github.com/whatwg/html/issues/3316. - Handle duplicate importScripts() as per https://github.com/w3c/ServiceWorker/issues/1041. - Replace *imported scripts updated flag* referenced in importScripts() by using service worker's state item. - Have Update's perform the fetch steps cover module scripts. - Avoid dobule-download of imported scripts pointed out in https://github.com/w3c/ServiceWorker/pull/1023#discussion_r92201798. This change basically makes it check out if the main script resource is identical to the existing resource. If so, it returns; otherwise, it creates a new service worker and evalute it to check out if any imported scripts are changed. It continues with Install only when any of the resources has been changed. With the change, importScripts() returns resources from the cache for any duplicated requests including the request for the main script. Fixes #1041, #1212, #1023. --- docs/index.bs | 81 +++++++++++++++++++++++++++++++-------------------- 1 file changed, 50 insertions(+), 31 deletions(-) diff --git a/docs/index.bs b/docs/index.bs index 0b5dd618..8119cd0c 100644 --- a/docs/index.bs +++ b/docs/index.bs @@ -165,7 +165,9 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe A [=/service worker=] has an associated skip waiting flag. Unless stated otherwise it is unset. - A [=/service worker=] has an associated imported scripts updated flag. It is initially unset. + A [=/service worker=] has an associated classic scripts imported flag. It is initially unset. + + A [=/service worker=] has an associated include updated resources flag. It is initially unset. A [=/service worker=] has an associated set of event types to handle (a [=ordered set|set=]) whose [=list/item=] is an event listener's event type. It is initially an empty set. @@ -2027,22 +2029,28 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe When the importScripts(|urls|) method is called on a {{ServiceWorkerGlobalScope}} object, the user agent *must* import scripts into worker global scope, given this {{ServiceWorkerGlobalScope}} object and |urls|, and with the following steps to [=fetching scripts/perform the fetch=] given the [=/request=] |request|: 1. Let |serviceWorker| be |request|'s [=request/client=]'s [=environment settings object/global object=]'s [=ServiceWorkerGlobalScope/service worker=]. - 1. If |serviceWorker|'s imported scripts updated flag is unset, then: - 1. Let |registration| be |serviceWorker|'s [=containing service worker registration=]. - 1. Set |request|'s [=service-workers mode=] to "`none`". - 1. Set |request|'s [=request/cache mode=] to "no-cache" if any of the following are true: - * |registration|'s [=service worker registration/update via cache mode=] is "`none`". - * The [=current global object=]'s [=force bypass cache for importscripts flag=] is set. - * |registration|'s [=last update check time=] is not null and the time difference in seconds calculated by the current time minus |registration|’s [=last update check time=] is greater than 86400. - 1. Let |response| be the result of fetching |request|. - 1. If |response|’s cache state is not "local", set |registration|’s [=service worker registration/last update check time=] to the current time. - 1. [=Extract a MIME type=] from the |response|'s [=unsafe response=]'s [=response/header list=]. If this MIME type (ignoring parameters) is not a [=JavaScript MIME type=], return a [=network error=]. - 1. If |response|'s unsafe response's [=response/type=] is not "error", and |response|'s [=response/status=] is an ok status, then: - 1. [=map/Set=] script resource map[|request|'s [=request/url=]] to |response|. - 1. Return |response|. - 1. Else: - 1. If script resource map[|url|] [=map/exists=], return script resource map[|url|]. - 1. Else, return a network error. + 1. If |serviceWorker|'s [=service worker/script resource map=][|request|'s [=request/url=]] [=map/exists=], return [=service worker/script resource map=][|request|'s [=request/url=]]. + 1. If |serviceWorker|'s [=state=] is *installed*, *activating*, *activated*, or *redundant*, return a [=network error=]. + 1. Let |registration| be |serviceWorker|'s [=containing service worker registration=]. + 1. Set |request|'s [=service-workers mode=] to "`none`". + 1. Set |request|'s [=request/cache mode=] to "no-cache" if any of the following are true: + * |registration|'s [=service worker registration/update via cache mode=] is "`none`". + * The [=current global object=]'s [=force bypass cache for importscripts flag=] is set. + * |registration|'s [=last update check time=] is not null and the time difference in seconds calculated by the current time minus |registration|’s [=last update check time=] is greater than 86400. + 1. Let |response| be the result of fetching |request|. + 1. If |response|’s cache state is not "local", set |registration|’s [=service worker registration/last update check time=] to the current time. + 1. [=Extract a MIME type=] from the |response|'s [=unsafe response=]'s [=response/header list=]. If this MIME type (ignoring parameters) is not a [=JavaScript MIME type=], return a [=network error=]. + 1. If |response|'s unsafe response's [=response/type=] is not "error", and |response|'s [=response/status=] is an ok status, then: + 1. Let |newestWorker| be the result of running [=Get Newest Worker=] with |registration|. + 1. Let |resource| be null. + 1. If |newestWorker| is not null, set |resource| to |newestWorker|'s [=service worker/script resource map=][|request|'s [=request/url=]], or null if it does not [=map/exist=]. + 1. Set |serviceWorker|'s [=service worker/include updated resources flag=] if any of the following are true: + * |newestWorker| is null. + * |resource| is null. + * |resource|'s [=response/body=] is not byte-for-byte identical with |response|'s [=response/body=]. + 1. [=map/Set=] [=service worker/script resource map=][|request|'s [=request/url=]] to |response|. + 1. Set |serviceWorker|'s [=classic scripts imported flag=]. + 1. Return |response|. @@ -2069,7 +2077,7 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe

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- [=/Service workers=] introduce new persistent storage features including scope to registration map (for [=/service worker registrations=] and their [=/service workers=]), [=request response list=] and name to cache map (for caches), and script resource map (for script resources). In order to protect users from any potential unsanctioned tracking threat, these persistent storages *should* be cleared when users intend to clear them and *should* maintain and interoperate with existing user controls e.g. purging all existing persistent storages. + [=/Service workers=] introduce new persistent storage features including scope to registration map (for [=/service worker registrations=] and their [=/service workers=]), [=request response list=] and name to cache map (for caches), and [=service worker/script resource map=] (for script resources). In order to protect users from any potential unsanctioned tracking threat, these persistent storages *should* be cleared when users intend to clear them and *should* maintain and interoperate with existing user controls e.g. purging all existing persistent storages.
@@ -2147,8 +2155,12 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe A job has a worker type ("classic" or "module"). + A [=job=] has a script resource map which is an ordered map where the keys are [=/URLs=] and the values are [=/responses=]. + A job has an update via cache mode, which is "`imports`", "`all`", or "`none`". + A [=job=] has a potentially include updated resources flag. It is initially unset. + A job has a client (a [=/service worker client=]). It is initially null. A job has a referrer (a [=/URL=] or null). @@ -2418,6 +2430,11 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe 1. Else: 1. Invoke [=Reject Job Promise=] with |job| and "{{SecurityError}}" {{DOMException}}. 1. Asynchronously complete these steps with a network error. + 1. Set |job|'s [=job/potentially include updated resources flag=] if any of the following are true: + * |newestWorker| is null. + * |newestWorker|'s [=classic scripts imported flag=] is set. + * |newestWorker|'s [=service worker/script resource map=][|request|'s [=request/url=]]'s [=response/body=] is not byte-for-byte identical with |response|'s [=response/body=]. + 1. Set |job|'s [=job/script resource map=][|request|'s [=request/url=]] to |response|. 1. If |response|'s cache state is not "local", set |registration|'s last update check time to the current time. Issue: The response's cache state concept had been removed from fetch. The fetch issue #376 tracks the request to restore the concept or add some similar way to check this state. @@ -2434,20 +2451,23 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe 1. Invoke Finish Job with |job| and abort these steps. Else, continue the rest of these steps after the algorithm's asynchronous completion, with |script| being the asynchronous completion value. - - 1. If |newestWorker| is not null, |newestWorker|'s [=service worker/script url=] [=url/equals=] |job|'s [=job/script url=], and |script|'s [=source text=] is a byte-for-byte match with |newestWorker|'s [=script resource=]'s [=source text=], if |script| is a [=classic script=], and |script|'s [=module script/module record=]'s \[[ECMAScriptCode]] is a byte-for-byte match with |newestWorker|'s [=script resource=]'s [=module script/module record=]'s \[[ECMAScriptCode]] otherwise, then: + 1. If |job|'s [=job/potentially include updated resources flag=] is unset, then: 1. Invoke [=Resolve Job Promise=] with |job| and |registration|. + 1. Invoke [=Finish Job=] with |job| and abort these steps. + 1. Let |worker| be a new [=/service worker=]. + 1. Set |worker|'s [=service worker/script url=] to |job|'s [=job/script url=], |worker|'s script resource to |script|, and |worker|'s [=service worker/type=] to |job|'s worker type. + 1. [=map/For each=] |url| → |response| of |job|'s [=job/script resource map=]: + 1. Set |worker|'s [=service worker/script resource map=][|url|] to |response|. + 1. Set |worker|'s script resource's HTTPS state to |httpsState|. + 1. Set |worker|'s script resource's [=script resource/referrer policy=] to |referrerPolicy|. + 1. Invoke Run Service Worker algorithm given |worker|, and with the *force bypass cache for importscripts flag* set if |job|'s [=job/force bypass cache flag=] is set. + 1. If an uncaught runtime script error occurs during the above step, then: + 1. Invoke [=Reject Job Promise=] with |job| and `TypeError`. + 1. If |newestWorker| is null, invoke Clear Registration algorithm passing |registration| as its argument. 1. Invoke Finish Job with |job| and abort these steps. - 1. Else: - 1. Let |worker| be a new [=/service worker=]. - 1. Set |worker|'s [=service worker/script url=] to |job|'s [=job/script url=], |worker|'s script resource to |script|, and |worker|'s [=service worker/type=] to |job|'s worker type. - 1. Set |worker|'s script resource's HTTPS state to |httpsState|. - 1. Set |worker|'s script resource's [=script resource/referrer policy=] to |referrerPolicy|. - 1. Invoke Run Service Worker algorithm given |worker|, and with the *force bypass cache for importscripts flag* set if |job|'s [=job/force bypass cache flag=] is set. - 1. If an uncaught runtime script error occurs during the above step, then: - 1. Invoke [=Reject Job Promise=] with |job| and `TypeError`. - 1. If |newestWorker| is null, invoke Clear Registration algorithm passing |registration| as its argument. - 1. Invoke Finish Job with |job| and abort these steps. + 1. If |worker|'s [=classic scripts imported flag=] is set, and |worker|'s [=service worker/include updated resources flag=] is unset, then: + 1. Invoke [=Resolve Job Promise=] with |job| and |registration|. + 1. Invoke [=Finish Job=] with |job| and abort these steps. 1. Invoke Install algorithm with |job|, |worker|, and |registration| as its arguments. @@ -2509,7 +2529,6 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe 1. Run the Update Registration State algorithm passing |registration|, "installing" and null as the arguments. 1. If |newestWorker| is null, invoke Clear Registration algorithm passing |registration| as its argument. 1. Invoke Finish Job with |job| and abort these steps. - 1. Set |registration|'s installing worker's imported scripts updated flag. 1. If |registration|'s waiting worker is not null, then: 1. [=Terminate Service Worker|Terminate=] |registration|'s [=waiting worker=]. 1. Run the [=Update Worker State=] algorithm passing |registration|'s [=waiting worker=] and *redundant* as the arguments.