[ovirt-devel] commons-collections v4.0
Alon Bar-Lev
alonbl at redhat.com
Thu May 8 06:43:38 UTC 2014
----- Original Message -----
> From: "Mike Kolesnik" <mkolesni at redhat.com>
> To: "Alon Bar-Lev" <alonbl at redhat.com>
> Cc: "yzaspits" <yzaspits at redhat.com>, devel at ovirt.org
> Sent: Thursday, May 8, 2014 7:18:51 AM
> Subject: Re: [ovirt-devel] commons-collections v4.0
>
> ----- Original Message -----
> >
> >
> > ----- Original Message -----
> > > From: "Yevgeny Zaspitsky" <yzaspits at redhat.com>
> > > To: "Alon Bar-Lev" <alonbl at redhat.com>, "Mike Kolesnik"
> > > <mkolesni at redhat.com>
> > > Cc: devel at ovirt.org
> > > Sent: Thursday, May 8, 2014 1:11:41 AM
> > > Subject: Re: [ovirt-devel] commons-collections v4.0
> > >
> > > On the other hand, changing a jar in the runtime environment without
> > > compiling and running test with the new jar could lead an application to
> > > stop functioning in a customer environment.
> > > Also not every bug found in a dependency jar would cause a problem in the
> > > application. (An application might not use the problematic part of the
> > > dependency.)
> > > I'd better trust the test suite (automatic and manual) that we run on the
> > > compiled application with all the dependencies that the developers choose
> > > at
> > > the development time and then deliver that (with its dependencies as a
> > > single package) to the customers.
> > > Every bug in a dependency should be evaluated within the given
> > > application
> > > scope and only if proven as the given application problem only then the
> > > application should be released.
> >
> > So what you basically claim is that java developers and technology is not
> > mature enough to keep backward compatibility, so each java developer should
> > freeze a snapshot in time for his application to work.
> >
> > I truly hope this is not the case.
>
> There can always be regressions as you're well aware, and I don't know but
> usually people who develop the libraries are not Einstein so yes, they do
> break
> backwards compatibility on occasions, sometimes even on purpose
> (deprecation).
>
> >
> > And for addressing your claim explicitly, what you can test at single point
> > in time, does not mean that it is definite as well, at customer site bugs
> > may be found also in the packages that you do test.
>
> Well, when you test on site by dev & qa you make sure you send something to
> the
> customer - X. When the dependencies are updated out of band, the customer
> actually is using X'.
> I can see at least 2 things wrong here:
> 1. You're putting the customer in a position of a tester for the X'
> application.
> 2. If customer finds a bug he actually found it on X', whereas the developer
> who
> would be assigned to the bug could be using X'' by now.
>
> If you're so keen on packaging a jar outside WAR file, we need to specify
> explicit version and not >=.
Explicit version is at if you pack it within your application, there is no point in that.
Think of how RHEL is provided, think of Fedora, in all cases there are components working together and each can be updated independently, and amazingly - it works. You can think of Windows with all of its libraries and interfaces (Microsoft or 3rd party), that application use, and it does work without every [sane] application pulls the entire dependencies.
For some reason only people with Java background (including the J2EE designers) assume that Java developers cannot be trusted for not breaking backward compatibility in minor versions. This is not technical assumption but human assumption, as there is no technical reason for Java library to break backward compatibility within minor releases, so what does it tells us about what Java developers thinks of them-selves?
Java will be ready for enterprise only when this is resolved. I hope all the dependencies we are using are at the quality level that enables us to to trust their developers.
>
> >
> > >
> > >
> > > Sent from Samsung Mobile
> > >
> > > -------- Original message --------
> > > From: Alon Bar-Lev <alonbl at redhat.com>
> > > Date: 07/05/2014 21:41 (GMT+02:00)
> > > To: Mike Kolesnik <mkolesni at redhat.com>
> > > Cc: Yevgeny Zaspitsky <yzaspits at redhat.com>,devel at ovirt.org
> > > Subject: Re: [ovirt-devel] commons-collections v4.0
> > >
> > >
> > >
> > > ----- Original Message -----
> > > > From: "Mike Kolesnik" <mkolesni at redhat.com>
> > > > To: "Alon Bar-Lev" <alonbl at redhat.com>
> > > > Cc: "Yevgeny Zaspitsky" <yzaspits at redhat.com>, devel at ovirt.org
> > > > Sent: Wednesday, May 7, 2014 9:34:03 PM
> > > > Subject: Re: [ovirt-devel] commons-collections v4.0
> > > >
> > > > ----- Original Message -----
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > > From: "Yevgeny Zaspitsky" <yzaspits at redhat.com>
> > > > > > To: "Alon Bar-Lev" <alonbl at redhat.com>
> > > > > > Cc: devel at ovirt.org
> > > > > > Sent: Tuesday, April 22, 2014 11:39:11 AM
> > > > > > Subject: Re: [ovirt-devel] commons-collections v4.0
> > > > > >
> > > > > > That means that we manage 2 separate environments:
> > > > > > 1. Development - relies on pom files. E.g. unit tests run with
> > > > > > commons-collections v3.1 (and when I add v4.0) and succeed.
> > > > >
> > > > > devenv will use runtime option.
> > > > > you are right about the unit tests, these relays on the poms.
> > > >
> > > > I use devenv and it always uses the dev option not the runtime.
> > > > So basically developers are using the pom specified versions and not
> > > > what
> > > > used in runtime.
> > > >
> > > > Even more so, in runtime it highly depends on what OS you're using, so
> > > > someone
> > > > developing on F19 might not be using same versions as a developer on
> > > > F20
> > > > and
> > > > both are probably very different versions than on RHEL/CentOS.
> > > > I won't even mention other OS`s.
> > > >
> > > > >
> > > > > > 2. Run-time - relies on JBoss own dependencies that bring
> > > > > > commons-collection
> > > > > > v3.2.1-redhat-2.
> > > > >
> > > > > in rhel case, yes.
> > > > >
> > > > > > This kind of discrepancies might be found in other libraries as we
> > > > > > do
> > > > > > not
> > > > > > synchronize our pom files with the JBoss current version
> > > > > > dependencies.
> > > > > > IMHO that could lead to some very difficult bugs that we won't be
> > > > > > able
> > > > > > to
> > > > > > simulate in our unit tests.
> > > > >
> > > > > correct, but the java way to pull dependencies at will without being
> > > > > able
> > > > > to
> > > > > fix z-stream using central package management tools is more severe
> > > > > than
> > > > > unit
> > > > > tests not working/not working.
> > > > >
> > > > > for example, your application uses x.jar and actually delivers
> > > > > x.jar...
> > > > > so
> > > > > from release to eternity it is your responsibility to track x.jar for
> > > > > severe
> > > > > stability bugs and security bugs, and release your entire application
> > > > > each
> > > > > time found, now multiple it with the # of components application is
> > > > > using
> > > > > and see how much effort you have just to maintain stability and
> > > > > security
> > > > > if
> > > > > you embed 3rd party components without your application.
> > > >
> > > > Yes, if you use package X then you're using that specific version with
> > > > it's
> > > > behaviour and API, this is why dependencies aren't updated light
> > > > headedly
> > > > but
> > > > with testing to see that nothing broke (since stuff does break, even in
> > > > minor
> > > > version, as we leave in a not so perfect world).
> > > >
> > > > >
> > > > > > Why do we avoid "to maintain our own packaging"? IMHO Ovirt own
> > > > > > dependencies
> > > > > > could be packed in the war, can't they?
> > > > >
> > > > > yes they could, but this is not suitable for enterprise grade
> > > > > implementations, mainly per what I described above.
> > > >
> > > > Sorry but AFAIK enterprise grade software release fixes for their
> > > > software
> > > > on a timely basis and have processes in place to manage upgrades of
> > > > functionality.
> > > >
> > > > What currently is done is relying on courtesy of other people to
> > > > release
> > > > a
> > > > "fix" that already exists a long time.
> > > > And of course, as I mentioned, the application needs to be tested with
> > > > the
> > > > updated library.
> > > > IMO neglecting this and leaving this out of band for "enterprise grade"
> > > > software is much worse than actually testing to see that it is working
> > > > and
> > > > just leaving it all to chance.
> > >
> > > Well, take the recent example of openssl issue that was found.
> > > Now, imagine that all products that use openssl should have been
> > > re-released.
> > > I think this is enough to understand how wrong this is.
> > >
> > > >
> > > > >
> > > > > Regards,
> > > > > Alon
> > > > >
> > > > > > Best regards,
> > > > > > ____________________
> > > > > > Yevgeny Zaspitsky
> > > > > > Senior Software Engineer
> > > > > > Red Hat Israel
> > > > > >
> > > > > >
> > > > > > ----- Original Message -----
> > > > > > From: "Alon Bar-Lev" <alonbl at redhat.com>
> > > > > > To: "Yevgeny Zaspitsky" <yzaspits at redhat.com>
> > > > > > Cc: devel at ovirt.org
> > > > > > Sent: Sunday, April 13, 2014 7:22:18 PM
> > > > > > Subject: Re: [ovirt-devel] commons-collections v4.0
> > > > > >
> > > > > >
> > > > > >
> > > > > > ----- Original Message -----
> > > > > > > From: "Yevgeny Zaspitsky" <yzaspits at redhat.com>
> > > > > > > To: devel at ovirt.org
> > > > > > > Sent: Sunday, April 13, 2014 7:13:10 PM
> > > > > > > Subject: [ovirt-devel] commons-collections v4.0
> > > > > > >
> > > > > > > Hi All,
> > > > > > >
> > > > > > > I'd like to add the new version (4.0) of Apache
> > > > > > > commons-collections
> > > > > > > library
> > > > > > > to the dependencies of the project (we use 3.1 currently).
> > > > > > > The new version uses the generics features of Java 5 so that make
> > > > > > > the
> > > > > > > code
> > > > > > > more type safe. You can find the full list of changes on
> > > > > > > https://commons.apache.org/proper/commons-collections/release_4_0.html.
> > > > > > > The new API is based on the original but it isn't fully
> > > > > > > compatible
> > > > > > > with
> > > > > > > it.
> > > > > > > So in order to make the migration to the new API easier, the
> > > > > > > package
> > > > > > > has
> > > > > > > been changed to org.apache.commons.collections4. That allows
> > > > > > > having
> > > > > > > both
> > > > > > > version of the library in the classpath at the starting point and
> > > > > > > move
> > > > > > > (refactor) towards the new version gradually.
> > > > > > >
> > > > > > > I have couple of questions regarding the new dependency:
> > > > > > > 1. Is there anything that could prevent adding the new
> > > > > > > dependency?
> > > > > >
> > > > > > We try to avoid introducing our own dependencies, in this case we
> > > > > > use
> > > > > > whatever jboss provides which is very comfortable as we do not need
> > > > > > to
> > > > > > maintain our own packaging.
> > > > > >
> > > > > > Currently the jbeap does not provide 4.0, it does support
> > > > > > 3.2.1-redhat-2,
> > > > > > so
> > > > > > better to avoid this until we switch to more recent version of
> > > > > > jboss.
> > > > > >
> > > > > > Alternatively we could enjoy standalone rpm within rhel/centos if
> > > > > > available,
> > > > > > however non exist.
> > > > > >
> > > > > > > 2. I did the change (http://gerrit.ovirt.org/26745).
> > > > > > > The unit tests that use the new dependency pass locally and in
> > > > > > > Jenkins
> > > > > > > environments.
> > > > > > > However when I try to run a code that is dependent on the
> > > > > > > newly
> > > > > > > added
> > > > > > > library NoClassDefFoundError being thrown.
> > > > > > > Also I can't find commons-collections4 jar under the
> > > > > > > installation
> > > > > > > directory. I use "make clean install-dev" command for
> > > > > > > building.
> > > > > > >
> > > > > > > Please advise.
> > > > >
> > > >
> > >
> >
>
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