Hi Georg, As far as I know, the only new documentation for SLING-7764 was the paragraph that was added to the README.md file at [1]
1. https://github.com/apache/sling-org-apache-sling-starter-startup/commit/389e0cbb58f33346f97bf730ae795269abf64d03 I did see the configuration options for the ServiceUnavailableFilter component and see that I can provide an alternate configuration value for the responseTextFor503 attribute to use some other custom page. So just to be clear, the migration path from the SLING-7764 solution to the new solution would be something like: a) Change the custom bundle that contained the custom_index.html file to no longer be a fragment bundle attached to the org.apache.sling.starter.startup artifact that no longer exists. The fragment can become a regular non-fragment bundle or the custom_index.html file can be moved somewhere else and get rid of the fragment bundle entirely. b) Modify the org.apache.felix.hc.core.impl.filter.ServiceUnavailableFilter-startupandshutdown service configuration to provide the alternate path to the custom page. For example, in the starter project (or a fork of it), change the responseTextFor503 value in the org-apache-sling-starter/src/main/provisioning/healthcheck.txt file. I guess the "custom" solution above is also a way to solve a custom build that does not include the "org.apache.sling.starter.content" bundle in the distribution? Or did you have something else in mind to provide better default behavior when that bundle is missing and the classpath:org.apache.sling.starter.content:content/content/startup/index.html file does not exist in the runtime? Regards, Eric On Thu, May 23, 2019 at 1:01 AM Georg Henzler <[email protected]> wrote: > Hi Eric, > > so there is [1] which I will extend a bit to be more specific about the > way to configure it (see [2] for metatype description). Is the mechanism > from SLING-7764 somewhere documented on Sling side? I would fix that > documentation then as well.... > > -Georg > > [1] > "It is possible to configure a custom response text/html" > > https://github.com/apache/felix/blob/trunk/healthcheck/README.md#service-unavailable-filter > > [2] > > https://github.com/apache/felix/blob/trunk/healthcheck/core/src/main/java/org/apache/felix/hc/core/impl/filter/ServiceUnavailableFilter.java#L118 > > On 2019-05-23 04:00, Eric Norman wrote: > > Hi Georg, > > > > I'm trying to digest what has been done here. It looks like this makes > > the > > solution that was done for > > https://issues.apache.org/jira/browse/SLING-7764 > > obsolete and breaks compatibility for any customization done via a > > fragment > > attached to the previous o.a.sling.starter.startup snapshot bundle? > > > > Have you provided any documentation on the expected technique for > > customizing the content of the page that is displayed when starting up > > or > > some guidance on how people would migrate from the old way to the new > > solution? > > > > Also what should happen for custom builds that don't include > > the org.apache.sling.starter.content artifact and still want a default > > "starting up" page to be displayed? > > > > > > Regards, > > Eric > > > > > > On Wed, May 22, 2019 at 3:35 PM Georg Henzler <[email protected]> > > wrote: > > > >> Hi all, > >> > >> I finished this, mostly with commit [1]. I moved some bundles into > >> different start levels for better startup behaviour (that way I got > >> could finish this without fixing SLING-8355 first). > >> > >> -Georg > >> > >> [1] > >> > >> > https://github.com/apache/sling-org-apache-sling-starter/commit/a16fb43f1d0333f74b066844e0377d93ca1e1e08 > >> > >> On 2019-05-14 11:05, Georg Henzler wrote: > >> > So I'll move forward with this and I created [1] to track this change. > >> > > >> > -Georg > >> > > >> > [1] https://issues.apache.org/jira/browse/SLING-8418 > >> > > >> > On 2019-04-08 10:49, Jörg Hoh wrote: > >> >> Hi Georg, > >> >> > >> >> ok, wasn't aware of the "100% compatibility mode" :-) So +1 from my > >> >> side. > >> >> > >> >> Jörg > >> >> > >> >> Am Mo., 8. Apr. 2019 um 00:28 Uhr schrieb Georg Henzler > >> >> <[email protected] > >> >>> : > >> >> > >> >>> Hi Jörg, > >> >>> > >> >>> there is the option "autoDisableFilter" [1] in the > >> >>> ServiceUnavailableFilter - if true the filter automatically > >> >>> unregisters > >> >>> itself upon first non-503 result. Once unregistered it listens to > >> >>> FrameworkEvent.STARTLEVEL_CHANGED events to reregister once needed > >> >>> (the > >> >>> shutdown case). During normal operations (that includes deployments > >> >>> that > >> >>> might cause the selected "systemalive" checks to be temporarily > >> >>> unavailable) the filter is not active (which is also good from a > >> >>> performance perspective). > >> >>> > >> >>> So really, all that would be needed to replace oas-startupfilter + > >> >>> -disabler and oas-starter-startup is the simple config [2] in the > >> >>> oas-starter provisioning model. > >> >>> > >> >>> -Georg > >> >>> > >> >>> [1] > >> >>> > >> >>> > >> > https://github.com/apache/felix/blob/d5245ba3ba306b57b83c4d5c6cfe499d955b0acb/healthcheck/core/src/main/java/org/apache/felix/hc/core/impl/filter/ServiceUnavailableFilter.java#L98 > >> >>> > >> >>> [2] > >> >>> > >> >>> org.apache.felix.hc.core.impl.filter.ServiceUnavailableFilter > >> >>> tags=["systemalive] > >> >>> > >> >>> osgi.http.whiteboard.context.select="(&( > >> osgi.http.whiteboard.context.name > >> >>> \=*)(!(osgi.http.whiteboard.context.name\=org.osgi.service.http)))" > >> >>> osgi.http.whiteboard.filter.regex=".*" > >> >>> autoDisableFilter=B"true" > >> >>> > >> >>> > >> >>> On 2019-04-07 19:49, Jörg Hoh wrote: > >> >>> > Hi Georg, > >> >>> > > >> >>> > Merging the 2 implementations oas-startupfilter + -disabler and > >> >>> > oas-starter-startup makes fully sense to me, although I am bit > >> hesitant > >> >>> > by > >> >>> > replacing the basic approach. > >> >>> > > >> >>> > these 2 have a rather static assumption, when the application is > up, > >> >>> > and > >> >>> > their sole purpose is to indicate that. And once the system is up, > >> it's > >> >>> > up > >> >>> > and this state remains unchanged until the startupfilterDisabler > is > >> >>> > deactivated. A healthcheck based implementation can changed its > mind > >> >>> > based > >> >>> > on many factors, you already mentioned the fact that key services > >> >>> > should be > >> >>> > available. If these services go down during runtime, the status of > >> this > >> >>> > check changes. > >> >>> > > >> >>> > If I understand you correctly, then the semantic of the startup > >> itself > >> >>> > might not change, but it's more likely, that the unavailability of > >> such > >> >>> > a > >> >>> > key service would cause the Filter to kick again, changing > >> >>> > runtime-behavior; currently it does not. > >> >>> > > >> >>> > Is this intended? > >> >>> > > >> >>> > Jörg > >> >>> > > >> >>> > > >> >>> > Am Sa., 6. Apr. 2019 um 00:24 Uhr schrieb Georg Henzler > >> >>> > <[email protected] > >> >>> >> : > >> >>> > > >> >>> >> Hi all, > >> >>> >> > >> >>> >> we have currently two mechanisms in Sling to wait for startup: > >> >>> >> > >> >>> >> * sling-org-apache-sling-startupfilter + > >> >>> >> sling-org-apache-sling-startupfilter-disabler > >> >>> >> * sling-org-apache-sling-starter-startup (only used for the > starter > >> >>> >> application AFAIK) > >> >>> >> > >> >>> >> Now that systemready in Felix is fully migrated to Felix Health > >> Checks > >> >>> >> I > >> >>> >> would like to rely on ServiceUnavailableFilter [1] instead. The > >> >>> >> advantage is that this filter can be configured in a declarative > >> >>> >> fashion > >> >>> >> (what is required to be alive can be configured, e.g. for a > customer > >> >>> >> project it's easy to wait for additional custom services) and > 503 is > >> >>> >> also correctly sent upon shutdown. > >> >>> >> > >> >>> >> Is this approach something everyone is ok with? > >> >>> >> > >> >>> >> -Georg > >> >>> >> > >> >>> >> [1] > >> >>> >> > >> >>> >> > >> >>> > >> > https://github.com/apache/felix/blob/trunk/healthcheck/core/src/main/java/org/apache/felix/hc/core/impl/filter/ServiceUnavailableFilter.java > >> >>> >> > >> >>> > >> >
