- From: Ben Kelly <bkelly@mozilla.com>
- Date: Fri, 10 Mar 2017 11:19:37 -0500
- To: Mike Pennisi <mike@bocoup.com>
- Cc: Webapps WG <public-webapps@w3.org>
- Message-ID: <CA+1UsbSb-UM1GJezpWf5GHaw5hbyfk2ASKY1n7L0BDSf1nujiQ@mail.gmail.com>
On Fri, Mar 10, 2017 at 11:10 AM, Mike Pennisi <mike@bocoup.com> wrote: > > The user agent may call this as often as it likes to check for updates. > > And further: > > > Note: Implementers may use the force bypass cache flag to aid debugging > (e.g. > > invocations from developer tools), and other specifications that extend > > service workers may also use the flag on their own needs. > > If I'm interpreting them correctly, these two details mean that any of a > Service Worker's lifecycle events (as well as a registration's > `updatefound` > event) may fire at any time. > Well, the lifecycle events would only fire in the *new* updated service worker. Once a service worker has activated, for example, its install event better never fire again. You are correct, though, these kind of weasel-words in the spec make testing harder > But to be able to test the implementation and validate that browsers are > working as per spec (and again, assuming my assessment is correct), this is > problematic. It makes it impossible to make any assertions about lifecycle > events observed over a given time frame. Any test for "normal" operation > (e.g. > call `registration.update()` and observe `updatefound` followed by > `install`, > followed finally by `active`) could be interrupted by an independent > invocation > of Soft Update. Would you agree? Or have I tripped myself up somewhere > along > the way? > In theory this is correct, but in practice its not a problem today AFAIK. If a browser implementation decided to randomly update service workers then they might start failing this kind of test. That browser, however, could also add an implementation-specific setting to disable this "random update" feature. I think we should test the spec'd update points and not worry about the "update at any time" non-normative text for now. Just my opinion. Ben
Received on Friday, 10 March 2017 16:20:16 UTC