Rather than using a relatively low level api such as ManagedServiceFactory I’d 
suggest considering a ds component with configuration required and supplying it 
with factory configurations to get multiple instances. By using a configuration 
annotation you can have the configuration injected in a typed form and you can 
supply default values for any keys not present in the factory configuration.

David Jencks 

Sent from my iPhone

> On Feb 23, 2018, at 6:32 AM, Leschke, Scott <slesc...@medline.com> wrote:
> 
> OK, that sounds like it may be a good approach.  Could you point me to the 
> Decanter code as a reference?
> 
> Thanks,
> 
> Scott
> 
> -----Original Message-----
> From: Jean-Baptiste Onofré [mailto:j...@nanthrax.net] 
> Sent: Thursday, February 22, 2018 9:53 PM
> To: user@karaf.apache.org
> Subject: Re: On another topic: Creating services programatically again
> 
> Hi Scott,
> 
> Service Managed Factory is the other way around: you start from the cfg file, 
> then the service is created. The content of the file can be default or 
> whatever, it doesn't matter.
> 
> Basically, you would have:
> 
> etc/org.scott.foo-one.cfg
> etc/org.scott.foo-two.cfg
> etc/org.scott.foo-three.cfg
> 
> with the corresponding service for each cfg file. If you create 
> etc/org.scott.foo-four.cfg, then, automatically,  you will have a new 
> corresponding service created.
> 
> For instance, it's what we are using in Decanter for the JMX collector: you 
> can create a new JMX collector "on the fly", just adding a new 
> etc/org.apache.karaf.decanter.collector.jmx-foobar.cfg file.
> 
> Regards
> JB
> 
>> On 02/23/2018 04:47 AM, Leschke, Scott wrote:
>> Thanks JB,
>> 
>> Initially, the .cfg would be populated almost entirely with the defaults  
>> the service receives using a configuration type so the idea is that the 
>> service creation needs to come first so that the service can be used to get 
>> the values to write the .cfg.
>> 
>> Is there a way to get those value without actually having a service instance 
>> or hard-coding them? 
>> 
>> Scott
>> 
>> -----Original Message-----
>> From: Jean-Baptiste Onofré [mailto:j...@nanthrax.net]
>> Sent: Thursday, February 22, 2018 9:38 PM
>> To: user@karaf.apache.org
>> Subject: Re: On another topic: Creating services programatically again
>> 
>> Hi Scott,
>> 
>> why don't use a managed service factory ?
>> 
>> It would automatically create a service based on a cfg. So for your user, he 
>> creates the cfg file, and then, automatically, the corresponding service is 
>> created.
>> 
>> Thoughts ?
>> 
>> Regards
>> JB
>> 
>>> On 02/22/2018 09:18 PM, Leschke, Scott wrote:
>>> As I mentioned a few weeks ago, I'm trying to create a service 
>>> instance programmatically and write the associated .cfg file for it.
>>> Based on feedback I got, I create the following method.
>>> 
>>>  
>>> 
>>> The goal is to create the service instance and then get its 
>>> configuration which at this point will mostly be the defaults that it 
>>> receives in its configuration type (hence my previous post). It 
>>> /appears/ to work, except what is really happening is that I get two 
>>> services. One is created by createFactoryConfguration call and the 
>>> other by Felix FileInstall after the .cfg file is written.
>>> 
>>>  
>>> 
>>> Actually I'm a bit surprised that placeholder .cfg file isn't created 
>>> if property /felix.fileinstall.filename/is defined, as I think that 
>>> would solve this problem, but perhaps there's another way?
>>> 
>>>  
>>> 
>>> Thoughts?
>>> 
>>> * *
>>> 
>>> * *
>>> 
>>> *private**void* createConfig(String cpid, String dir, String name, 
>>> Map<String,Object> props)
>>> 
>>>        *throws* Exception
>>> 
>>> {
>>> 
>>>        Configuration conf =
>>> parent.cfgAdmin.createFactoryConfiguration(cpid, "?");
>>> 
>>>  
>>> 
>>>        dir  = (dir.endsWith("/") ? dir : dir + '/');
>>> 
>>>        name = name.replaceAll(" ", "_").toLowerCase();
>>> 
>>>        File cfg = *new* File(dir + cpid + '-' + name + ".cfg");
>>> 
>>>  
>>> 
>>>        Dictionary<String,Object> confProps = toDictionary(props);
>>> 
>>>        confProps.put("felix.fileinstall.filename",
>>> cfg.toURI().toString());
>>> 
>>>  
>>> 
>>>        *try*
>>> 
>>>        {
>>> 
>>>               conf.update(confProps);
>>> 
>>>  
>>> 
>>>               // Get the properties for the new service object
>>> 
>>>               props = getProps(conf.getPid());
>>> 
>>>  
>>> 
>>>               // Create .cfg file with initial property set
>>> 
>>>               ITemplate tmp = parent.templateMgr.getTemplate(
>>> configTemplates.get(cpid) );
>>> 
>>>               tmp.bind("cfg", props);
>>> 
>>>  
>>> 
>>>               *try* (FileLineWriter w = *new* FileLineWriter(cfg))
>>> 
>>>               {
>>> 
>>>                      w.putLine(tmp.render());
>>> 
>>>               }
>>> 
>>>        }
>>> 
>>>        *catch* (Exception e)
>>> 
>>>        {
>>> 
>>>               cfg.delete();
>>> 
>>>               conf.delete();
>>> 
>>>               *throw* e;
>>> 
>>>        }
>>> 
>>> }
>>> 
>>>  
>>> 
>> 
>> --
>> Jean-Baptiste Onofré
>> jbono...@apache.org
>> http://blog.nanthrax.net
>> Talend - http://www.talend.com
>> 
> 
> --
> Jean-Baptiste Onofré
> jbono...@apache.org
> http://blog.nanthrax.net
> Talend - http://www.talend.com

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