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From Martin Nielsen <mny...@gmail.com>
Subject Re: Configurator R7 example
Date Thu, 12 Jul 2018 20:39:40 GMT
Hi David

I started managedproperties before tjat specification was finished and i
havent really used it, as ManagedProperties has been my goto configadmin
communication method. I will highlight the main functions of it, but i cant
say if DS can do it too now. But the advantages are:

The configuration is just an interface, so it can be easily replaced for
testing purposes.
You can use any class you want for config items, not just primitives. URL,
file, Datetime, Instant or whatever you can parse to a string os fair game.
You can write validation logic to check any configuration item before it is
changed. For example if you have a string that must be valid regex, or an
URL that needs to actually resolve, or a filepath where the file must
exist. If the validation code fails, the config is not updated. With this,
a silly spelling mistake will be caught, and you wont stop your production
server because pf sausage fingers:)
You can implement a configuration interface to supply easy and versitile
defaults. If you want to do random generatio, get defaults from a database,
initiate a new selfsigned certificate or whatever, practically anything is
possible.
You can register callbacks so you can take action when the configuration is
changed, for example if you have a Soap Server that has to reboot to take
in  new configuration.
You can use the configuration interface to save new configurations simply
by adding a matching setter. That means that you can have an application
admin change configurations for that specific bundle without letting them
loose in the entire app server. Saving in this way is also subject to
validation.
When a configuration is registered, it will also be availableaa a service,
so although a specific bundne owns it, other bundles can also read it.
Of cause we use MetaType as well, so it is possible to supply defaults,
suggested values, cardinalities and so on.


I am sorry that i dont really have a good grip on the new standard, so i
can't tell you exactly where each one falæs short. But i can say that
ManagedProperties can do the things it can because we found out we needed
it, especially the validation. You can only kill a production server
because you mistyped a file name so many times before do something to fix
it:)



On 12 Jul 2018 20:11, "Philipp Höfler" <Philipp.Hoefler@pernexas.com> wrote:

Thanks for your very detailed explanation.
If I got you right, with ManagedProperties I am not bound to the primitives
the default osgi implementation provides, but I can use any Java type.

Up to now, I think I am fine with factory configuration, but probably I
come back to you in a few weeks, when I realize that the scenario is more
complex as I thought

Anyhow, thanks for your help.
I am quite new to all the osgi stuff, but slowly but surely I am getting a
picture of it.

-----Ursprüngliche Nachricht-----
Von: Martin Nielsen <mnybon@gmail.com>
Gesendet: Donnerstag, 12. Juli 2018 19:53

An: users@felix.apache.org
Betreff: Re: Configurator R7 example

Hello everyone

I saw ManagedProperties mentioned so now I appear!

@Philipp.Hoefler if what you mean by complex types is that you want the
configuration admin to return some more advanced types like URLs Files or
Dates, then ManagedProperties will handle that for you. If not then stop
reading:)

If you want to use ManagedProperties and have questions, you can write me.
I am very talkative:)

ManagedProperties is made to handle mapping and propper handling of
advanced or complex types to the Configuration Admin. It works through the
java util Proxy as a middle layer, allowing an application to request
complex types like Dates or URLs while storing them as primitives and
Strings in the Configuration Admin.

In order to use a ManagedProperties, you register an annotated interface
with the ManagedProperties service, like so:

First you create the interface which will serve as your configuration

package my.package.config;
import dk.netdesign.common.osgi.config.annotation.Property;
import dk.netdesign.common.osgi.config.annotation.PropertyDefinition;
import dk.netdesign.common.osgi.config.exception.UnknownValueException;

@PropertyDefinition
public interface MyConfiguration {
@Property(type = String.class, typeMapper = ExistingFileFilter.class)
throws UnknownValueException public File getExistingFile();

@Property(type = String.class, typeMapper = URLMapper.class) throws
UnknownValueException public File getURL(); @Property public String
getUsername(); }

Then you register it with a bundle, either through an activator or through
Declarative Services

@Component
public class MyComponent {
ManagedPropertiesService mpRegistration; MyConfiguration config; @Activate
    public void register(BundleContext context) throws
InstantiationException, IllegalAccessException, InvalidSyntaxException {
     config = mpRegistration.register(MyConfiguration.class, context); }
@Reference(cardinality = ReferenceCardinality.MANDATORY) public void
setManagedPropertiesService(ManagedPropertiesService
managedPropertiesService) throws Exception {
     mpRegistration = managedPropertiesService; } }

This will create a configuration in the ConfigurationAdmin with 3
configurations, ExistingFile, URL and Username. Calling the getter methods
in the interface will return the current configuration, which means that it
will update if it gets changed in the WebConsole or anywhere else.

If you want you can pass a number of defaults with the config registration
like this:
config = mpRegistration.register(MyConfiguration.class, new
MyConfigurationDefaults(), context);

MyConfigurationDefaults is simply a class that implements the
MyConfiguration interface. The defaults come into play if no configuration
is found, for example if no configuration has been set yet, or if a single
configuration item was not set.
The Defaults class can do anything basically, if you want configuration
from a database or a webservice, it is possible.

This setup has the following advantages:
1. Since the Configuration is simply an interface it is easily tested
outside OSGi, by creating a setter or extra constructor for the interface.
Then you can simply pass whatever you want to the test, no need for
configuration admin or anything.
2. The defaults can be a powerful fallback for missing configuration.
3. When handling complex types, ManagedProperties can test the input and
fail the configuration update if something doesn't add up. This is very
useful for handling complex types, as you don't want to acidentally write
something that won't parse to what you want. For example, say you only want
to be able to specify files which actually exist.

public class ExistingFileFilter extends TypeFilter<String, File> {

    @Override
    public File parse(String input) throws TypeFilterException {
        File f = new File(input);
        try {
            f.getCanonicalPath();

        } catch (IOException ex) {
            throw new TypeFilterException("Could not read the file '" +
input + "'. Could not resolve path: " + ex.getMessage(), ex);
        }
        return f;
    }
    @Override
    public String revert(File input) throws TypeFilterException {
        try {
            return input.getCanonicalPath();
        } catch (IOException ex) {
            throw new TypeFilterException("Could not parse file", ex);
        }
    }
    @Override
    public void validate(File toValidate) throws TypeFilterException {
        try {
            String path = toValidate.getCanonicalPath();
            if (!toValidate.exists()) {
                throw new TypeFilterException("Could not parse file. The
file " + path + " did not exist");
            }
        } catch (IOException ex) {
            throw new TypeFilterException("Could not read the file '" +
toValidate + "'. Could not resolve path: " + ex.getMessage(), ex);
        }
    }
}

If the configuration is updated with a filename that is either not a proper
filename, or the file does not exist on the system, the entire
configuration update will throw a ConfigurationUpdate and fail. Other use
cases could be propper URLS, or defining username/password combinations
which are actually valid.


ManagedProperties cannot currently create one return type based of several
configuration items. For example, say you have 3 configuration items:
Protocol, Host and Port, and you want that converted to single "getURL"
method. That is not CURRENTLY possible.


ManagedProperties has a few other cool features:

Callbacks:
You can register callback classes which are triggered when the
configuration is updated. This is very useful if you have something like a
Database connection, which only takes its configuration at construction
time.

Setters:
You can define matching setters on the interface getter methods. This will
allow you to change the configuration in the ConfigAdmin directly though
the application. This can be really useful if you want to give an
applcation admin power over the configuration for that application, but
aren't interested in allowing him full admin access to the container.

Wicket Integration:
A special page has been created for Wicket which can present the
configuration of a select configuration PID, which will make an
application-specific configuration page that much easier to implement.

On Thu, Jul 12, 2018 at 6:22 PM, Raymond Auge <raymond.auge@liferay.com>
wrote:

> On Thu, Jul 12, 2018 at 11:58 AM, Philipp Höfler <
> Philipp.Hoefler@pernexas.com> wrote:
>
> > Right, this is missing.
> > I added the @RquireConfigurator annotation to the GoGo Command
> > class. Is that a suitable place for it?
> > The json is now being loaded. The value is set to false.
> >
> > Could you please explain, how this is working?
> >
> It's not completely clear to me, why the @interface MyConfig is
> > automatically used to hold the configuration.
> >
>
> DS is merely creating a proxy of the annotation type which fronts (or
> is backed by) the configuration dictionary, using the default values
> as well, default values if that particular property is not defined or
> if no configuration is available.
>
>
> > In each class, that needs access to the config I've a activate and
> > modified method with this signature: public void modified(MyConfig
> config)
> >
> > Is the type resolved based on the pid and the param type of the method?
> >
>
> The Component Property Type will be backed by whatever configuration
> is associated with the component. so if you use the same Component
> Property Types on two different components which refer to two
> different pids, the proxies will show different values (based on the
> backing configuration dictionary of the component).
>
>
>
> >
> > ---
> > Back to my root problem:
> > Is it now possible to have the following configuration?
> > {
> >         // Resource Format Version
> >     ":configurator:resource-version" : 1,
> >
> >         // First Configuration
> >    "my.config":
> >    {
> >                 "system1":
> >         {
> >                         "test.securityEnabled": false,
> >                         "test.test": false
> >                 },
> >                 "system2":
> >         {
> >                         "test.securityEnabled": false,
> >                         "test.test": false
> >                 }
> >         }
> > }
> >
>
> Sure in this case the configuration dictionary will hold values:
>
> system1 = {"test.securityEnabled": false, "test.test": false}
> system2 = {"test.securityEnabled": false, "test.test": false}
>
> which is probably not what you intended.
>
> IF what you want is to create N instances of the component, one per
> set of configuration properties, you'd want to use Factory Configurations
like so:
>
> {
> >         // Resource Format Version
> >     ":configurator:resource-version" : 1,
> >
> >         // First Configuration
> >    "my.config~system1":
> >    {
> >                         "test.securityEnabled": false,
> >                         "test.test": false
> >                 },
> >         // Second Configuration
> >    "my.config~system2":
> >    {
> >                         "test.securityEnabled": true,
> >                         "test.test": false
> >                 }
> >         }
> > }
> >
>
> Then you will have 2 component activations; one for each system1,
> system2, each with a MyConfig instance backing a different factory
> configuration instance.
>
> HTH
> - Ray
>
>
> >
> > Is it possible to have such a config with n systems?
> > Meaning, I do not know the amount of systems at compile time.
> >
> > Further, how would the @interface MyConfig annotation look like?
> > Is it possible to expect an array of MyConfig for the
> > modified(MyConfig[]
> > configs) method?
> >
> > Thanks for your help,
> > Philipp
> >
> > -----Ursprüngliche Nachricht-----
> > Von: Raymond Auge <raymond.auge@liferay.com>
> > Gesendet: Donnerstag, 12. Juli 2018 16:43
> > An: felix users <users@felix.apache.org>
> > Betreff: Re: Configurator R7 example
> >
> > Did you add the requirement to your configuration bundle?
> >
> > Require-Capability: osgi.extender; \
> >      filter:="(&(osgi.extender=osgi.configurator) \
> >              (version>=1.0
> > <https://osgi.org/specification/osgi.cmpn/7.0.0/
> > service.configurator.html#org.osgi.service.configurator>)(!(
> > version>=2.0)))"
> >
> > That or on some bit of code in the configuration bundle add the
> annotation:
> >
> > @org.osgi.service.configurator.annotations.RequireConfigurator
> >
> > - Ray
> >
> >
> > On Thu, Jul 12, 2018 at 10:23 AM, Philipp Höfler <
> > Philipp.Hoefler@pernexas.com> wrote:
> >
> > > Hallo David,
> > >
> > > thanks for the explanation.
> > > So, the configurator is just a "wrapper" for the
> > > ConfigAdminService to read json and transfer it into a key value
format, right?
> > >
> > > I still have problems to use the
> > > I put a test.json file in the OSGI-INF/configurator folder of a
> > > bundle with the following content:
> > > {
> > >   // Resource Format Version
> > >   ":configurator:resource-version" : 1,
> > >
> > >   // First Configuration
> > >   "my.config":
> > >   {
> > >     "test.securityEnabled": false,
> > >     "test.test": false
> > >   }
> > > }
> > >
> > > In addition, I have an annotation for holding the values:
> > > public @interface MyConfig
> > > {
> > >     boolean test_securityEnabled () default true;
> > >     boolean test_test() default true; }
> > >
> > > Besides that, I've a custom GoGo command for configuration. But I
> > > am not sure, if this is really needed for loading the json?
> > >
> > > Unfortunately, the json is obviously not loaded.
> > > Both values are set to true, according to the default value.
> > >
> > > Do I have to do something in addition to load the json file?
> > >
> > > Thanks,
> > > Philipp
> > >
> > > -----Ursprüngliche Nachricht-----
> > > Von: David Bosschaert <david.bosschaert@gmail.com>
> > > Gesendet: Donnerstag, 12. Juli 2018 11:15
> > > An: users@felix.apache.org
> > > Betreff: Re: Configurator R7 example
> > >
> > > Hi Philipp,
> > >
> > > In the end the configuration specified with the Configurator will
> > > end up in OSGi Configuration Admin, so the Configurator is limited
> > > to the same types as ConfigAdmin. The Configurator allows complex
> > > JSON values to be specified, they will end up as JSON text in
> > > Configuration Admin if they go beyond what ConfigAdmin supports
natively.
> > >
> > > So to use the Configurator you need the Configurator bundle plus
> > > the ConfigAdmin bundle.
> > >
> > > The Configurator handles configuration resources in
> > > OSGI-INF/configurator inside bundles but can also be provided with
> > > external configuration via the configurator.initial
> > > framework/system property. This is described in sections 150.4 and
> > > 150.5 in [1]. To provide Configurator configuration into the
> > > system you don't need to write any classes, but depending on how
> > > you use the configuration you may have to add classes that consume
> > > it. But again, the consumption can be done by anything that
> > > understands ConfigAdmin configs, so there
> > are a lot of options for this.
> > >
> > > I'm not aware of a complete tutorial on this topic yet. I agree it
> > > would be nice to have that.
> > >
> > > Hope this helps,
> > >
> > > David
> > >
> > > [1] https://osgi.org/specification/osgi.cmpn/7.0.0/
> > > service.configurator.html
> > >
> > > On Thu, 12 Jul 2018 at 10:55, Philipp Höfler
> > > <Philipp.Hoefler@pernexas.com
> > > >
> > > wrote:
> > >
> > > > Hi,
> > > >
> > > > I am searching for a possibility to load complex configurations.
> > > > I tried the ConfigurationAdminService, but key value pairs are
> > > > not sufficient as I need complex types.
> > > >
> > > > Raymond pointed out that I should have a look at the
> > > > Configurator Specification.
> > > > https://osgi.org/specification/osgi.cmpn/7.0.0/service.configurator.
> > > > ht
> > > > ml
> > > >
> > > > I read the specification and it sounds promising.
> > > > But I am stuck how to use the Configuration in my project.
> > > > I understand that I've to add the following dependency.
> > > > org.apache.felix.configurator
> > > >
> > > > But I don't understand if I've to add some classes, where the
> > > > json file has to be placed and if it's possible to place it
> > > > outside of the
> > > bundle?
> > > >
> > > > Is there any tutorial or sample project out there?
> > > >
> > > > Thanks,
> > > > Philipp
> > > >
> > >
> > > ------------------------------------------------------------------
> > > --- To unsubscribe, e-mail: users-unsubscribe@felix.apache.org

> > > For additional commands, e-mail: users-help@felix.apache.org
> > >
> >
> >
> >
> > --
> > *Raymond Augé* <http://www.liferay.com/web/raymond.auge/profile>
> >  (@rotty3000)
> > Senior Software Architect *Liferay, Inc.* <http://www.liferay.com>
> >  (@Liferay)
> > Board Member & EEG Co-Chair, OSGi Alliance <http://osgi.org>
> > (@OSGiAlliance)
> >
> > --------------------------------------------------------------------
> > - To unsubscribe, e-mail: users-unsubscribe@felix.apache.org

> > For additional commands, e-mail: users-help@felix.apache.org
> >
>
>
>
> --
> *Raymond Augé* <http://www.liferay.com/web/raymond.auge/profile>
>  (@rotty3000)
> Senior Software Architect *Liferay, Inc.* <http://www.liferay.com>
>  (@Liferay)
> Board Member & EEG Co-Chair, OSGi Alliance <http://osgi.org>
> (@OSGiAlliance)
>

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