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From Stephen Connolly <stephen.alan.conno...@gmail.com>
Subject Re: Maven and JPA/EclipseLink Configuration...
Date Wed, 10 Jul 2013 15:45:24 GMT
On 10 July 2013 15:52, Ron Wheeler <rwheeler@artifact-software.com> wrote:

>  On 10/07/2013 10:06 AM, Stephen Connolly wrote:
>
> Well if it is an interactive installer then it can do the configuration
> for you...
>
>   It needs to be interactive in some way if you want to handle a variety
> of environments.
>
> ./configure
> make
> install
> (you hope that you don't end up with something this complex!!!)
>
> or  questions during msi or rpm installs.
>
>
>  But with a JavaEE application you don't know:
>
>  1. What application container they have
> 2. What database they have
> 3. Where the application container picks up deployed apps
> 4. How the user wants the app deployed in the application container
> ...
>
>
> These are all questions that can be asked and are somewhat limited by the
> configurations that your application supports.
> I would think that the answer to question 1 limits the possible responses
> to 3 and 4.
>
> The application designer  usually limits the supported configurations in
> some way so that they do not have to create and distribute a lot of
> configuration files if they are using Maven to build the final war file
> that has to handle the whole range of deployment environments.
>
>
Well getting back to the OP, they were saying that they are expanding the
supported list of platforms... so it looks like their designer is getting
more fast and loose with QA (because QA will only be doing touchstone
testing on the entire matrix of combinations)


> As a frequent deployer and a less frequent developer, I prefer an
> installer that encapsulates the developers supported tweaking rather than a
> complex process that requires me to manually modify configuration files
> based on my understanding of the developers documentation.
>

I am not saying you're wrong... I am saying that the JavaEE spec does not
share your point of view...

The ideal Maven way is one .ear that works for everyone without
modification. The JavaEE spec and the way application containers are
implemented makes that harder to achieve for some scopes (e.g.
persistence.xml)


> I generally have very little idea about the internal architecture since I
> might have to install 50 packages to get a server set up and don't have the
> time to learn each one and read the code and configuration file
> documentation to find the things to change.
>

Take it up with the JCP ;-)


> I want to get something that the programmer has tested and will install on
> the supported configuration with as few places for me  to make mistakes, as
> possible.
>
>
Which is why I recommended having Maven do the repacking for them... just
using one module for each target platform...

Note that this may mean that they have 20 or 30 repack modules... so be
it!!! Following the Maven way typically results in discovering pain at
things which are not best practice... the need to have NxM repack-ear
modules highlights the pain introduced by poor application server spec
design


>
>
>
>  I can go on.
>
>  The less Windows centric world has installers that basically are
> non-interactive, e.g. RPM, DEB, etc
>
>  This type of installer typically would be installing both the
> application and container... thus the question is moot.
>
>  An example of this is the various ways you can install Jenkins:
>
>  1. Jenkins.war (as self-executing war file)
> 2. Jenkins.war in your container of choice
> 3. RPM
> 4. DEB
> 5. PKG
> 6. Windows installer
> 7. Mac installer
>
>  All except the .WAR based distributions make assumptions about how to
> deploy the application.
>
>  If you want to install Jenkins on RedHat, you grab the RPM and install
> that... but if you don't like the way that configures Jenkins, then you can
> grab your container of choice, grab the .war and deploy that in your
> container using your container's deployment toolchain.
>
>  Installers are not the solution to this problem... in fact to my mind,
> other than windows, they are often an anti-pattern...
>
>  Though with puppet/chef what you typically do is wrap up the application
> you want in an installer that depends on an installer you created for your
> container of choice and then drops the application into the correct
> directory... that simplifies your puppet/chef scripts as they just interact
> with the platform's package management infrastructure... but you are still
> back to the Ops team creating the installer not the dev team
>
>
> On 10 July 2013 14:39, Ron Wheeler <rwheeler@artifact-software.com> wrote:
>
>> Where does an installer fit in this vision?
>>
>> It seems to me, having installed thousands of programs as a Windows user
>> and Linux system administrator, that a lot of the discussion about
>> deployment issues seem to ignore the role of installers (rpm, msi, izPack,
>> etc.).
>>
>> They are specifically designed to tweak packages during deployment.
>>
>> They can be set up very easily to be very smart about using input from
>> the Application Deployer and Administrator or from the environment
>> directly, to customize the installed application.
>>
>> Ron
>>
>>
>>
>> On 10/07/2013 4:23 AM, Stephen Connolly wrote:
>>
>>>  Well the first thing I would look towards is whether you can use an
>>> application server specific deployment descriptor to tweak the effective
>>> persistence.xml at deployment time.
>>>
>>> I am not saying that the above is possible, but if it is, then that is
>>> obviously "the way to go" as you then can just bundle all the application
>>> server specific deployment descriptors into the .ear and you have one
>>> .ear
>>> that works for everyone.
>>>
>>> I have a constant battle with people in work who feel that application
>>> server specific deployment descriptors are an anti-pattern... and if you
>>> think it is ok to follow the JavaEE spec's vision of the deployment
>>> process, then that may indeed be a valid view... but the real world does
>>> not work that way... and hence you need the application server specific
>>> deployment descriptors.
>>>
>>> Ok let's take a step back, and look at where I am coming from.
>>>
>>> The JavaEE spec lists a role of application deployer:
>>>
>>>  *# Application Deployer and Administrator
>>>
>>>> *The application deployer and administrator is the company or person
>>>> who
>>>>
>>>> configures and deploys application clients, web applications, Enterprise
>>>> JavaBeans components, and Java EE applications, administers the
>>>> computing
>>>> and networking infrastructure where Java EE components and applications
>>>> run, and oversees the runtime environment. Duties include setting
>>>> transaction controls and security attributes and specifying connections
>>>> to
>>>> databases.
>>>> During configuration, the deployer follows instructions supplied by the
>>>> application component provider to resolve external dependencies, specify
>>>> security settings, and assign transaction attributes. During
>>>> installation,
>>>> the deployer moves the application components to the server and
>>>> generates
>>>> the container-specific classes and interfaces.
>>>> A deployer or system administrator performs the following tasks to
>>>> install
>>>> and configure a Java EE application or components:
>>>> * Configures the Java EE application or components for the operational
>>>> environment
>>>> * Verifies that the contents of the EAR, JAR, and/or WAR files are well
>>>> formed and comply with the Java EE specification
>>>> * Deploys (installs) the Java EE application or components into the Java
>>>> EE server
>>>>
>>>
>>> *Source: http://docs.oracle.com/javaee/6/tutorial/doc/bnaca.html*
>>> *
>>>
>>> *
>>> Now the "vision" is thus that whoever is deploying the application will
>>> essentially "crack open" the .ear, tweak the deployment descriptors and
>>> then seal it back up again (that is meaning of the "Configures the Java
>>> EE
>>> application or components for the operational environment" step which
>>> comes
>>> *before* deploying to the JavaEE server)
>>>
>>> Of course where we hit issues is that we all view letting a human "crack
>>> open", "tweak", and "seal up again" a .ear as error prone, plus the
>>> people
>>> we are shipping the application to also view this as scary.
>>>
>>> Now if I were the admin for such an app, I would use something like
>>> puppet
>>> or chef, etc to automate the open-tweak-seal process... but the biggest
>>> issue is tracablility.
>>>
>>> If you have a .ear that is never the same as that shipped from the vendor
>>> (or from the release process) how do you know that it was the one that QA
>>> tested?
>>>
>>> Instead of being able to do
>>>
>>> sha1sum application.ear
>>>
>>> you now have to open up the ear and do a diff of the contents against the
>>> reference .ear and potentially resolve differences in files that are
>>> permitted to have differences.
>>>
>>> TL;DR the JavaEE spec vision is not something that you want
>>>
>>> So then you decide that you want to release the app pre-configured for
>>> each
>>> deployment environment and all the remaining configuration should be
>>> picked
>>> up via JNDI or via files deployed to the classpath of the container (or
>>> maybe system properties or environment variables)
>>>
>>> In an ideal world you can do it all from JNDI or system properties (JNDI
>>> being better as you do not pollute a global name space)
>>>
>>> In the non-ideal world what you do is have your build system take on some
>>> of the roles of application deployer.
>>>
>>> You have a module that produces the generic .ear
>>>
>>> And then you have modules that unpack-tweak-repack the .ear targetting
>>> each
>>> app server/database
>>>
>>> That is "the maven way" *but* it is not the way Maven wants you to
>>> work...
>>> Maven wants you to only have one .ear that works for all... the app
>>> servers
>>> are letting you down, and Maven is delivering pain for not following the
>>> best practice way of working.
>>>
>>>
>>> On 10 July 2013 08:33, John Patrick <nhoj.patrick@gmail.com> wrote:
>>>
>>>  On 10 Jul 2013, at 06:05, Baptiste MATHUS <bmathus@batmat.net> wrote:
>>>>
>>>>  If those properties are specific to eclipselink, then I think it's ok
>>>>> and
>>>>> simpler to just leave them in the persistence.xml even if they're
>>>>>
>>>> actually
>>>>
>>>>> not used when EclipseLink isn't the provider. Then package only one
>>>>> ear.
>>>>>
>>>>> Cheers
>>>>>
>>>>>
>>>>> 2013/7/9 John Patrick <nhoj.patrick@gmail.com>
>>>>>
>>>>>  I'm working on a project that uses JPA EclipseLink, everything started
>>>>>>
>>>>>  of
>>>>
>>>>>  fine with Jetty for developers development and WebLogic and Oracle
>>>>>>
>>>>>  proper
>>>>
>>>>>  ear deployments.
>>>>>>
>>>>>> EclipseLink has two values that need to be set in persistence.xml
>>>>>>
>>>>>  depending
>>>>
>>>>>  upon your Application Server and Database;
>>>>>> eclipselink.target-server
>>>>>> eclipselink.target-database
>>>>>>
>>>>>> This mean we have two profiles, Jetty and Release.
>>>>>>
>>>>>> Now we support WebSphere and DB2, so have gone to 5 profiles and
the
>>>>>>
>>>>>  need
>>>>
>>>>>  to rebuild the ear 4 times which each profile.
>>>>>>
>>>>>> Profiles
>>>>>> Jetty
>>>>>> WLSOracle
>>>>>> WLSDB2
>>>>>> WASOracle
>>>>>> WASDB2
>>>>>>
>>>>>> I feel I'm doing something wrong...
>>>>>>
>>>>>> Does someone have any suggestions on what to look at so i could
>>>>>>
>>>>>  potentially
>>>>
>>>>>  build it once and get all the 4 ears build in one command? I've
>>>>>> thought
>>>>>> about types or classifiers but unsure if that is just another hack...
>>>>>>
>>>>>> Thoughts? As we soon might also need to support MySQL and Glassfish
so
>>>>>> their is another 5 profiles and 5 more builds for a release.
>>>>>>
>>>>>> John
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Baptiste <Batmat> MATHUS - http://batmat.net
>>>>> Sauvez un arbre,
>>>>> Mangez un castor !
>>>>>
>>>> Mathus I think you miss understood my point. I need to build 4
>>>> different ears currently as eclipselink auto detections fails about
>>>> once a week and we can reproduce on demand.
>>>>
>>>> each ear has a different combination of values.
>>>>
>>>> ear 1 = WebLogic / Oracle
>>>> ear 2 = WebLogic / DB2
>>>> ear 3 = WebSphere / Oracle
>>>> ear 4 = WebSphere / DB2
>>>>
>>>> I can't build one ear, say ear 1 as the value for the database setting
>>>> would be wrong when DB2 is the backend. Also the value for the
>>>> application server would be wrong when deployed to WebSphere.
>>>>
>>>> If eclipselink auto detect worked 100% I could create one ear but a
>>>> few issues in production which we can't reproduce in test on demand
>>>> mean we need to explicitly define application server and database
>>>> server.
>>>>
>>>>  From the off list replies it looks like others are having similar
>>>> issues and doing similar things.
>>>>
>>>> cheers,
>>>> John
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscribe@maven.apache.org
>>>> For additional commands, e-mail: users-help@maven.apache.org
>>>>
>>>>
>>>>
>>
>> --
>> Ron Wheeler
>> President
>> Artifact Software Inc
>> email: rwheeler@artifact-software.com
>> skype: ronaldmwheeler
>> phone: 866-970-2435, ext 102
>>
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@maven.apache.org
>> For additional commands, e-mail: users-help@maven.apache.org
>>
>>
>
>
> --
> Ron Wheeler
> President
> Artifact Software Inc
> email: rwheeler@artifact-software.com
> skype: ronaldmwheeler
> phone: 866-970-2435, ext 102
>
>

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