That works for me, I'll make the necessary changes.

On Thu, Aug 1, 2019 at 10:08 AM Dave Neuman <[email protected]> wrote:

> Good summary Jeremy.
> I agree with Rawlin, I think it is reasonable to allow jobs to be changed
> up until they are active (using PUT) and also allow them to be DELETED at
> any time.
>
> On Thu, Aug 1, 2019 at 9:28 AM Rawlin Peters <[email protected]>
> wrote:
>
> > I think you summed that up pretty well, Jeremy. @ocket8888 did bring
> > up a good point about the fact that you can submit a job without it
> > becoming active right away, so in theory you could be able to update a
> > revalidation before it actually becomes active. Maybe we should allow
> > PUT only when the job is "active", but you can DELETE a job at any
> > time. I do like the idea of the UI warning about deleting a job that
> > has already been activated, but the PUT of an "active" job should be
> > prohibited by the API _and_ UI IMO.
> >
> > - Rawlin
> >
> > On Thu, Aug 1, 2019 at 8:20 AM Jeremy Mitchell <[email protected]>
> > wrote:
> > >
> > > My understanding (and someone better versed in ATS please correct me if
> > i'm
> > > wrong) is that when you create a "invalidate/revalidate job" for a
> > delivery
> > > service, the following things happen:
> > >
> > > 1. the job is inserted into the job table. duh.
> > > 2. the reval_pending flag on ALL servers that belong to the delivery
> > > service's CDN is set to true (seems like overkill tbh when a delivery
> > > service may only be assigned to a subset of a cdn's servers but that's
> > > another discussion)
> > > 3. every minute, a cache will check if their reval_pending flag = true,
> > if
> > > so that cache will pull a new regex_revalidate.config file that will
> > > contain all the jobs for the cache's cdn where TTL < now
> > >
> > > now a new "rule" exists in the regex_revalidate.config to represent
> that
> > > new job:
> > >
> > > http://my.origin.com/foo.png 1567346310 <-- september 1 (one month
> from
> > now)
> > >
> > > when a request comes in to the cache for foo.png, ATS consults
> > > regex_revalidate.config and notices the rule and therefore, revalidates
> > the
> > > content (ignores what's in cache and goes back upstream). This is the
> > only
> > > time ATS will do this. It will only exercise this rule ONCE. foo.png is
> > now
> > > cacheable again going forward.
> > >
> > > Now imagine this delivery services is assigned to 50 caches across the
> > > country and this is a very active delivery service. Within 10 minutes,
> a
> > > request for foo.png has come in to each of the 50 caches and the new
> > > regex_revalidate rule has been exercised on each cache. So basically
> that
> > > rule is "done". it has done the job it was intended to do.
> > Editing/deleting
> > > this job will not change what's already been done.
> > >
> > > However, because of the TTL that was set on the job, the following rule
> > > will remain in regex_revalidate.config for a month
> > >
> > > http://my.origin.com/foo.png 1567346310 <-- september 1 (one month
> from
> > now)
> > >
> > > and ATS still needs to consult the rule to determine if it has been
> > > exercised or not. So there is some processing that needs to be done
> even
> > on
> > > a rule that is already done. I think I heard that when regex_revalidate
> > > gets really long, it can cause performance issues.
> > >
> > > Long story short. Does providing edit/delete of a job potentially
> provide
> > > false hope to the user? But like you, I can see value in both. Edit
> would
> > > be great if you screw it up and notice right away. Delete would be
> great
> > > for those jobs we know are done but have this huge TTL on them that is
> > > sucking up ATS performance unnecessarily.  I know, I'm overthinking
> this.
> > > If others are good with edit/delete of jobs, I'm good. Maybe on
> > > edit/delete, the UI just needs some sort of warning "you realize you
> are
> > > editing/deleting a job that may have already been processed. continue?"
> > >
> > > Jeremy
> > >
> > >
> > >
> > > On Thu, Aug 1, 2019 at 7:38 AM ocket 8888 <[email protected]> wrote:
> > >
> > > > Do jobs not run constantly for their TTL? I guess I just assumed
> that a
> > > > revalidation would remain active until it's over, meaning that
> matching
> > > > content can't be cached in that duration. But I suppose that would be
> > > > unnecessary if content had just changed and wasn't constantly in that
> > > > window.
> > > > Still, though, that should just change what can be fixed in that
> > window.
> > > > You can't change the fact that cache servers might unnecessarily do a
> > lot
> > > > of work to revalidate content that hasn't changed, but if you forget
> to
> > > > e.g. make the TTL the same length as the Cache-Control-Max-Age header
> > then
> > > > you can still fix it.
> > > >
> > > > I'll take out the PATCH method immediately since there seems to be
> > > > consensus that it's not a good idea at the moment, but I'd still like
> > to
> > > > wait a bit to see if anyone else wants to chime in on PUT, since I'm
> > still
> > > > convinced editing jobs could be useful.
> > > >
> > > >
> > > > On Wed, Jul 31, 2019 at 10:49 AM Jeremy Mitchell <
> > [email protected]>
> > > > wrote:
> > > >
> > > > > > the most common runtime for a job is 178 hours, and the vast
> > majority
> > > > are
> > > > > at least 48. You effectively have the entire runtime of a job to
> > "fix" it
> > > > > if need be
> > > > >
> > > > > i believe it is common practice to set the TTL (runtime) of the
> > > > invalidate
> > > > > job to line up with the cache control max age value. that way they
> > can
> > > > > guarantee that the content is either revalidated OR expires from
> > cache.
> > > > >
> > > > > however, in practice, if the delivery service is very active (lots
> of
> > > > > requests), the content could be revalidated in minutes? across the
> > whole
> > > > > cdn so i don't think its true that you "effectively have the entire
> > > > runtime
> > > > > of a job to "fix" it if need be"
> > > > >
> > > > > i think that's why we've never had edit/delete because once the job
> > is
> > > > > created and deployed to the cache (used to be every 15 minutes but
> > now is
> > > > > every 1 minute), the job is out there running. not saying i don't
> > agree
> > > > > with the ability or the need to edit/delete. i'm just saying it's
> > tricky.
> > > > >
> > > > >
> > > > >
> > > > > On Wed, Jul 31, 2019 at 10:33 AM ocket8888 <[email protected]>
> > wrote:
> > > > >
> > > > > > I should also mention that in both PUT and PATCH, the only
> mutable
> > > > parts
> > > > > > of a job are the regular expression, the TTL and the start time.
> > Which
> > > > > > is another point I should make regarding 'you only have 60
> seconds
> > to
> > > > > > edit/delete a job', because actually the start time must be in
> the
> > > > > > future, and could be set up to (but using the user/current/jobs
> > > > > > endpoint, no more than) two days in advance.
> > > > > >
> > > > > > On 7/31/19 10:12 AM, Chris Lemmons wrote:
> > > > > > > While I see the value in PATCH, Rawlin is spot on: we need
> > defined
> > > > > > > behaviour around null and missing fields in the patches. (One
> > > > > > > alternative: jsonpatch. It's more verbose, but clearly defines
> > the
> > > > > > > edge cases.)
> > > > > > >
> > > > > > > PATCH is also very dangerous unless you support If-Match, which
> > we
> > > > > > > don't. But that's a problem we should also fix everywhere. It's
> > not
> > > > > > > unique to this endpoint.
> > > > > > >
> > > > > > > On Tue, Jul 30, 2019 at 4:49 PM Rawlin Peters <
> > > > [email protected]
> > > > > >
> > > > > > wrote:
> > > > > > >> In my opinion, introducing PATCH methods seems like
> unnecessary
> > > > > > >> complexity. We don't really have a good way in TO-Go to
> support
> > > > > > >> partial object updates in a holistic manner today, and there
> are
> > > > some
> > > > > > >> difficulties around determining which fields were actually
> sent
> > by a
> > > > > > >> client with a null value (e.g. `"foo": null`) vs fields that
> > were
> > > > > > >> entirely omitted by the client. It would also add to the
> burden
> > of
> > > > > > >> testing and maintenance (when a simple PUT implementation
> would
> > > > > > >> suffice), and I don't think there's a great way for the TO Go
> > client
> > > > > > >> to marshal a lib/go-tc struct into a PATCH request that only
> > > > contains
> > > > > > >> the fields you'd like to update (sometimes with null/empty
> > values).
> > > > > > >>
> > > > > > >> As for PUT, I think we could get by with a POST and a DELETE
> > > > without a
> > > > > > >> PUT for this particular endpoint, but I'm not sure I really
> feel
> > > > > > >> strongly about that. Providing the ability to PUT kind of
> > encourages
> > > > > > >> the idea that you don't really have to get your invalidations
> > right
> > > > > > >> the first time, or that you can just update an existing
> > invalidation
> > > > > > >> job to change the regex instead of creating a new invalidation
> > with
> > > > a
> > > > > > >> different regex (when really they should be created as
> separate
> > > > jobs).
> > > > > > >> If you have a bad revalidation deployed, your first priority
> > should
> > > > > > >> probably be to get rid of it as quickly as possible (via
> DELETE)
> > > > > > >> instead of trying to replace it with a different regex (via
> > PUT). In
> > > > > > >> that case, I'd think it would be advantageous to only provide
> > the
> > > > > > >> DELETE option instead of both DELETE and PUT. First delete the
> > bad
> > > > > > >> invalidation ASAP, then work on a better regex.
> > > > > > >>
> > > > > > >> - Rawlin
> > > > > > >>
> > > > > > >> On Tue, Jul 30, 2019 at 10:31 AM ocket8888 <
> [email protected]
> > >
> > > > > wrote:
> > > > > > >>> I have had this PR open for a while:
> > > > > > >>> https://github.com/apache/trafficcontrol/pull/3744
> > > > > > >>>
> > > > > > >>> I meant to bring this to the mailing list earlier, but I
> > forgot :P
> > > > > > >>>
> > > > > > >>> The reason this merits discussion is that the PR adds several
> > > > method
> > > > > > >>> handlers to the /jobs endpoint that didn't exist in Perl:
> > > > > > >>>
> > > > > > >>> - POST
> > > > > > >>>
> > > > > > >>>       lets users create new jobs directly at this endpoint.
> My
> > hope
> > > > > is
> > > > > > >>> that the /user/current/jobs endpoint will fall into disuse,
> > and we
> > > > > can
> > > > > > >>> consolidate some functionality in one place. Obviously, this
> > > > > > >>> necessitates a CDN-wide queue of reval updates.
> > > > > > >>>
> > > > > > >>> - PUT
> > > > > > >>>
> > > > > > >>>       allows jobs to be replaced. This queues reval updates
> > > > CDN-wide.
> > > > > > >>>
> > > > > > >>> - PATCH
> > > > > > >>>
> > > > > > >>>       allows jobs to be edited. This also queues reval
> updates
> > > > > CDN-wide
> > > > > > >>>
> > > > > > >>> - DELETE
> > > > > > >>>
> > > > > > >>>       deletes jobs. This, too, queues reval updates CDN-wide
> > > > > > >>>
> > > > > > >>>
> > > > > > >>> Which I think is a good idea. Without any way to mutate
> created
> > > > > jobs, a
> > > > > > >>> typo can have dire consequences that can't be taken back. But
> > since
> > > > > > >>> POST->DELETE->POST is really just editing with more steps, a
> > > > > PUT/PATCH
> > > > > > >>> seemed to make sense.
> > > > > > >>>
> > > > > > >>>
> > > > > > >>> thoughts?
> > > > > > >>>
> > > > > >
> > > > >
> > > >
> >
>

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