[ 
https://issues.apache.org/jira/browse/CAMEL-11810?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Grzegorz Grzybek updated CAMEL-11810:
-------------------------------------
    Description: 
I have a case where one bundle/blueprint-container defines:
{code:xml}
    <bean id="messageIdRepositoryImpl" 
class="org.apache.camel.processor.idempotent.MemoryIdempotentRepository"/>

    <service id="messageIdRepository" 
interface="org.apache.camel.spi.IdempotentRepository" 
ref="messageIdRepositoryImpl" />
{code}

and another one defines Camel context with:
{code:xml}
    <reference id="messageIdRepository" 
interface="org.apache.camel.spi.IdempotentRepository"/>
    <camelContext xmlns="http://camel.apache.org/schema/blueprint";>

        <route id="xx">

            <from 
uri="file://xxx?y=z&amp;readLock=idempotent&amp;idempotent=true&amp;idempotentRepository=#messageIdRepository&amp;other.properties[...]"
 />
{code}

The problem is that when bundle defining {{messageIdRepositoryImpl}} is 
stopped, stopping bundle/blueprint-container with camel context that references 
{{messageIdRepositoryImpl}} leads to wait on Proxy/ReferenceRecipe:
{noformat}
org.osgi.service.blueprint.container.ServiceUnavailableException: Timeout 
expired when waiting for mandatory OSGi service reference: 
(objectClass=org.apache.camel.spi.IdempotentRepository)
        at 
org.apache.aries.blueprint.container.ReferenceRecipe.getService(ReferenceRecipe.java:234)
        at 
org.apache.aries.blueprint.container.ReferenceRecipe.access$000(ReferenceRecipe.java:56)
        at 
org.apache.aries.blueprint.container.ReferenceRecipe$ServiceDispatcher.call(ReferenceRecipe.java:306)
        at Proxy28f0d520_9465_4682_9ec1_02ae44e9fa4a.toString(Unknown Source)
        at java.lang.String.valueOf(String.java:2994)[:1.8.0_144]
        at java.lang.StringBuilder.append(StringBuilder.java:131)[:1.8.0_144]
        at 
org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3214)
        at 
org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3234)
        at 
org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3222)
        at 
org.apache.camel.impl.DefaultCamelContext.doStop(DefaultCamelContext.java:3101)
        at org.apache.camel.support.ServiceSupport.stop(ServiceSupport.java:102)
        at 
org.apache.camel.blueprint.BlueprintCamelContext.destroy(BlueprintCamelContext.java:129)
...
{noformat}

There are few problems here. First - {{GenericFileEndpoint.doStart()}} does 
this:
{code:java}
if (idempotentRepository != null) {
    getCamelContext().addService(idempotentRepository, true);
}
{code}

which adds the blueprint recipe (proxy) to 
{{org.apache.camel.impl.DefaultCamelContext#servicesToStop}} without a way to 
specify {{stopOnShutdown=false}}.

IMO services obtained from OSGi registry should not be tied to lifecycle of 
single context with route having {{#referenceToOsgiOrBlueprintService}} in 
endpoint URI.

Also - the above stack trace is not retrieved when stopping an osgi service, 
but when log.warning an exception!:
{code:xml}
log.warn("Error occurred while shutting down service: " + service + ". This 
exception will be ignored.", e);
{code}
In the above code we have implicit {{toString()}} call on service which leads 
to another proxy call which calls 
{{org.apache.aries.blueprint.container.ReferenceRecipe.ServiceDispatcher#call()}}
 → {{org.apache.aries.blueprint.container.ReferenceRecipe#getService()}} → 
{{org.apache.aries.blueprint.container.ReferenceRecipe#monitor.wait(metadata.getTimeout()}}.

The most obvious fix is to move idempotent repository to a blueprint file where 
file endpoint is used.

But as OSGi devil's advocate, I suggest more generic solution: when looking up 
objects inside {{org.apache.camel.blueprint.BlueprintContainerRegistry}}, in 
addition to calling 
{{org.osgi.service.blueprint.container.BlueprintContainer#getComponentInstance()}}
 we may check if {{blueprintContainer.getComponentMetadata(name) instanceof 
ReferenceMetadata}} and in such case return a proxied proxy that would prevent 
waiting for blueprint reference when we're stopping the context - we'd have to 
check if the target service is available anyway (why ReferenceRecipe doesn't 
have a method like "tryGetService()"?)...

Less generic fix could be to add a flag used instead of default:
{code:java}
// idempotent repository may be used by others, so add it as a service so its 
stopped when CamelContext stops
if (idempotentRepository != null) {
    getCamelContext().addService(idempotentRepository, true);
}
{code}

so user could decide whether idempotent repository is or isn't "external" 
("shared").

  was:
I have a case where one bundle/blueprint-container defines:
{code:xml}
    <bean id="messageIdRepositoryImpl" 
class="org.apache.camel.processor.idempotent.MemoryIdempotentRepository"/>

    <service id="messageIdRepository" 
interface="org.apache.camel.spi.IdempotentRepository" 
ref="messageIdRepositoryImpl" />
{code}

and another one defines Camel context with:
{code:xml}
    <reference id="messageIdRepository" 
interface="org.apache.camel.spi.IdempotentRepository"/>
    <camelContext xmlns="http://camel.apache.org/schema/blueprint";>

        <route id="xx">

            <from 
uri="file://xxx?y=z&amp;readLock=idempotent&amp;idempotent=true&amp;idempotentRepository=#messageIdRepository&amp;other.properties[...]"
 />
{code}

The problem is that when bundle defining {{messageIdRepositoryImpl}} is 
stopped, stopping bundle/blueprint-container leads to wait on 
Proxy/ReferenceRecipe:
{noformat}
org.osgi.service.blueprint.container.ServiceUnavailableException: Timeout 
expired when waiting for mandatory OSGi service reference: 
(objectClass=org.apache.camel.spi.IdempotentRepository)
        at 
org.apache.aries.blueprint.container.ReferenceRecipe.getService(ReferenceRecipe.java:234)
        at 
org.apache.aries.blueprint.container.ReferenceRecipe.access$000(ReferenceRecipe.java:56)
        at 
org.apache.aries.blueprint.container.ReferenceRecipe$ServiceDispatcher.call(ReferenceRecipe.java:306)
        at Proxy28f0d520_9465_4682_9ec1_02ae44e9fa4a.toString(Unknown Source)
        at java.lang.String.valueOf(String.java:2994)[:1.8.0_144]
        at java.lang.StringBuilder.append(StringBuilder.java:131)[:1.8.0_144]
        at 
org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3214)
        at 
org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3234)
        at 
org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3222)
        at 
org.apache.camel.impl.DefaultCamelContext.doStop(DefaultCamelContext.java:3101)
        at org.apache.camel.support.ServiceSupport.stop(ServiceSupport.java:102)
        at 
org.apache.camel.blueprint.BlueprintCamelContext.destroy(BlueprintCamelContext.java:129)
...
{noformat}

There are few problems here. First - {{GenericFileEndpoint.doStart()}} does 
this:
{code:java}
if (idempotentRepository != null) {
    getCamelContext().addService(idempotentRepository, true);
}
{code}

which adds the blueprint recipe (proxy) to 
{{org.apache.camel.impl.DefaultCamelContext#servicesToStop}} without a way to 
specify {{stopOnShutdown=false}}.

IMO services obtained from OSGi registry should not be tied to lifecycle of 
single context with route having {{#referenceToOsgiOrBlueprintService}} in 
endpoint URI.

Also - the above stack trace is not retrieved when stopping an osgi service, 
but when log.warning an exception!:
{code:xml}
log.warn("Error occurred while shutting down service: " + service + ". This 
exception will be ignored.", e);
{code}
In the above code we have implicit {{toString()}} call on service which leads 
to another proxy call which calls 
{{org.apache.aries.blueprint.container.ReferenceRecipe.ServiceDispatcher#call()}}
 → {{org.apache.aries.blueprint.container.ReferenceRecipe#getService()}} → 
{{org.apache.aries.blueprint.container.ReferenceRecipe#monitor.wait(metadata.getTimeout()}}.

The most obvious fix is to move idempotent repository to a blueprint file where 
file endpoint is used.

But as OSGi devil's advocate, I suggest more generic solution: when looking up 
objects inside {{org.apache.camel.blueprint.BlueprintContainerRegistry}}, in 
addition to calling 
{{org.osgi.service.blueprint.container.BlueprintContainer#getComponentInstance()}}
 we may check if {{blueprintContainer.getComponentMetadata(name) instanceof 
ReferenceMetadata}} and in such case return a proxied proxy that would prevent 
waiting for blueprint reference when we're stopping the context - we'd have to 
check if the target service is available anyway (why ReferenceRecipe doesn't 
have a method like "tryGetService()"?)...

Less generic fix could be to add a flag used instead of default:
{code:java}
// idempotent repository may be used by others, so add it as a service so its 
stopped when CamelContext stops
if (idempotentRepository != null) {
    getCamelContext().addService(idempotentRepository, true);
}
{code}

so user could decide whether idempotent repository is or isn't "external" 
("shared").


> Lifecycle problems for services retrieved from Blueprint container
> ------------------------------------------------------------------
>
>                 Key: CAMEL-11810
>                 URL: https://issues.apache.org/jira/browse/CAMEL-11810
>             Project: Camel
>          Issue Type: Bug
>          Components: camel-blueprint
>            Reporter: Grzegorz Grzybek
>            Assignee: Grzegorz Grzybek
>
> I have a case where one bundle/blueprint-container defines:
> {code:xml}
>     <bean id="messageIdRepositoryImpl" 
> class="org.apache.camel.processor.idempotent.MemoryIdempotentRepository"/>
>     <service id="messageIdRepository" 
> interface="org.apache.camel.spi.IdempotentRepository" 
> ref="messageIdRepositoryImpl" />
> {code}
> and another one defines Camel context with:
> {code:xml}
>     <reference id="messageIdRepository" 
> interface="org.apache.camel.spi.IdempotentRepository"/>
>     <camelContext xmlns="http://camel.apache.org/schema/blueprint";>
>         <route id="xx">
>             <from 
> uri="file://xxx?y=z&amp;readLock=idempotent&amp;idempotent=true&amp;idempotentRepository=#messageIdRepository&amp;other.properties[...]"
>  />
> {code}
> The problem is that when bundle defining {{messageIdRepositoryImpl}} is 
> stopped, stopping bundle/blueprint-container with camel context that 
> references {{messageIdRepositoryImpl}} leads to wait on Proxy/ReferenceRecipe:
> {noformat}
> org.osgi.service.blueprint.container.ServiceUnavailableException: Timeout 
> expired when waiting for mandatory OSGi service reference: 
> (objectClass=org.apache.camel.spi.IdempotentRepository)
>       at 
> org.apache.aries.blueprint.container.ReferenceRecipe.getService(ReferenceRecipe.java:234)
>       at 
> org.apache.aries.blueprint.container.ReferenceRecipe.access$000(ReferenceRecipe.java:56)
>       at 
> org.apache.aries.blueprint.container.ReferenceRecipe$ServiceDispatcher.call(ReferenceRecipe.java:306)
>       at Proxy28f0d520_9465_4682_9ec1_02ae44e9fa4a.toString(Unknown Source)
>       at java.lang.String.valueOf(String.java:2994)[:1.8.0_144]
>       at java.lang.StringBuilder.append(StringBuilder.java:131)[:1.8.0_144]
>       at 
> org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3214)
>       at 
> org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3234)
>       at 
> org.apache.camel.impl.DefaultCamelContext.shutdownServices(DefaultCamelContext.java:3222)
>       at 
> org.apache.camel.impl.DefaultCamelContext.doStop(DefaultCamelContext.java:3101)
>       at org.apache.camel.support.ServiceSupport.stop(ServiceSupport.java:102)
>       at 
> org.apache.camel.blueprint.BlueprintCamelContext.destroy(BlueprintCamelContext.java:129)
> ...
> {noformat}
> There are few problems here. First - {{GenericFileEndpoint.doStart()}} does 
> this:
> {code:java}
> if (idempotentRepository != null) {
>     getCamelContext().addService(idempotentRepository, true);
> }
> {code}
> which adds the blueprint recipe (proxy) to 
> {{org.apache.camel.impl.DefaultCamelContext#servicesToStop}} without a way to 
> specify {{stopOnShutdown=false}}.
> IMO services obtained from OSGi registry should not be tied to lifecycle of 
> single context with route having {{#referenceToOsgiOrBlueprintService}} in 
> endpoint URI.
> Also - the above stack trace is not retrieved when stopping an osgi service, 
> but when log.warning an exception!:
> {code:xml}
> log.warn("Error occurred while shutting down service: " + service + ". This 
> exception will be ignored.", e);
> {code}
> In the above code we have implicit {{toString()}} call on service which leads 
> to another proxy call which calls 
> {{org.apache.aries.blueprint.container.ReferenceRecipe.ServiceDispatcher#call()}}
>  → {{org.apache.aries.blueprint.container.ReferenceRecipe#getService()}} → 
> {{org.apache.aries.blueprint.container.ReferenceRecipe#monitor.wait(metadata.getTimeout()}}.
> The most obvious fix is to move idempotent repository to a blueprint file 
> where file endpoint is used.
> But as OSGi devil's advocate, I suggest more generic solution: when looking 
> up objects inside {{org.apache.camel.blueprint.BlueprintContainerRegistry}}, 
> in addition to calling 
> {{org.osgi.service.blueprint.container.BlueprintContainer#getComponentInstance()}}
>  we may check if {{blueprintContainer.getComponentMetadata(name) instanceof 
> ReferenceMetadata}} and in such case return a proxied proxy that would 
> prevent waiting for blueprint reference when we're stopping the context - 
> we'd have to check if the target service is available anyway (why 
> ReferenceRecipe doesn't have a method like "tryGetService()"?)...
> Less generic fix could be to add a flag used instead of default:
> {code:java}
> // idempotent repository may be used by others, so add it as a service so its 
> stopped when CamelContext stops
> if (idempotentRepository != null) {
>     getCamelContext().addService(idempotentRepository, true);
> }
> {code}
> so user could decide whether idempotent repository is or isn't "external" 
> ("shared").



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