Looking for some help handling the error conditions that may occur during camel route(s) startup in a context. We are using java dsl to create routes after reading a configuration. when one of the configuration is wrong (e.g. missing host name in sftp uri. runtime discovery of error in this case), all subsequent routes are not even started by camel. What we are trying to achieve is, log an error for faulty case and proceed with subsequent route.
Is there any interceptor for same?
I would need more information to provide you with a more exact answer; however, it looks like you should be able to use the onException clause as part of RouteBuilder configuration. Here is an excerpt from the JBoss Camel guide:
Scopes
The onException clauses can be effective in either of the following scopes:
RouteBuilder scope—onException clauses defined as standalone statements inside a RouteBuilder.configure() method affect all of the routes defined in that RouteBuilder instance. On the other hand, these onException clauses have no effect whatsoever on routes defined inside any other RouteBuilder instance. The onException clauses must appear before the route definitions.
All of the examples up to this point are defined using the RouteBuilder scope.
Route scope—onException clauses can also be embedded directly within a route. These onException clauses affect only the route in which they are defined.
https://access.redhat.com/documentation/en-US/Red_Hat_JBoss_Fuse/6.1/html-single/Apache_Camel_Development_Guide/#BasicPrinciples-ExceptionHandling
Related
I have an application where I have custom lifecycle strategy for camel context start. This strategy has some logic which checked onCamelStart "event". Let's say it checks if cluster formed or not. If not, VetoCamelContextStartException thrown and thus context not started.
But I got warning with message like "clash of names for camel context" and name with prefix -n is used to register camel context into mbean server. Camel handle duplication in such a way As result I see couple of beans in jmx console.
DefaultManagementLifecycleStrategy is used to register mbeans (added in ManagmentStrategyFactory) and it can unmanage mbeans during onCamelStop.
As result I have next sequence of events which manifest into duplication of mbeans:
Start of Camel Context.
DefaultManagementLifecycleStrategy register all mbeans
CustomLifecycleStrategy puts the veto for start.
DefaultManagementLifecycleStrategy uregister all mbeans when onStop invoked.
Camel context marked as stopped.
Camel context is starting and registration of mbeans repeats.
Start of Camel context is vetoed again
Camel doesn't stop context due to it is already stopped (marked as stopped) and as result all mbeans are still in place.
Camel starts again and duplication of mbeans occurs.
We haven't seen such warning and duplication of mbeans in 2.17.7. Is it some bug in Camel? Or are we doing something wrong conceptually?
I have migrated Camel from 2.17.7 to 2.25.4. I am using Spring Boot and my camel context is defined in xml.
I have a couple of Apache Camel routes created using the Java DSL and Spring.
#Bean
public CamelContext camelContext() throws Exception {
CamelContext camelContext = new DefaultCamelContext();
camelContext.addRoutes(route1bean());
...
camelContext.start();
return camelContext;
}
These routes use quartz2 component for scheduling and everything works as expected.
The jobs can however have errors when running and there is a requirement to retry them manually. I'm looking for a way to make adhoc manual execution of the route using hawtio or in Java code.
Yes , use jconsole. There are many mbeans exposed by camel. You can use them to start and stop. Of course you can do the same using Hawtio as well.
Updated based on your comment:
I get what you mean, This is the approach I will take. Create 3 routes. 2 light weight routes - Route A with Simple File From endpoint, Route B with Cron and Route C with direct:bla From endpoint, which contains the actual business logic. This way, you can trigger Route A whenever you want, Route C is common, Irrespective of when Route B is triggered by the cron.
I'm new to Camel and bit confused between CamelContext and Registry.
As far as I know that CamelContext is the base object like ApplicationContext in Spring that is used for add routes and maintains the camel life cycle.
Also we got the Registry object from CamelContext but not sure what is the main purpose of this registry.
My intention is to add the component in the context/registry so that JNDIBind can look up the components.
CamelContext: Kind of Camel Runtime that keeps everything in Camel together, e.g.: Endpoints, TypeConverter, Routes, Components and Registry(!).
Registry: allows you to lookup beans, which by default will be JNDI beans. If you use the spring integration it will be Spring's ApplicationContext.
Generally camel when used with spring makes use of the ApplicationContextRegistry to lookup components, endpoints etc with the name of the bean defined in spring-bean.xml file. In places where we need to use JNDIRegistry we would have to add that registry when creating the CamelContext. This is used in places where JNDI objects are shared accross multiple JVMs where JNDI is the best solution.
Please see different types of registry implementation for camel: camel registries
I have two web-service call in my fuse service. I need to implement retry when time out occurs in only one of the web service call.how can i achieve that in fuse.
A redelivery policy can be specified for an Exception Clause (onException) or an Error Handler. Both of them can be applied to either global (per RouteBuilder instance) or route scope. So you'll have to put your web service calls into two separate routes.
First of all thanks to folks who are currently involved in the development of Camel, I am grateful for all the hard work they have put in.
I am looking for some design advice.
The architecture is something like this:
I have a bunch of Java classes which when instantiated are required to connect to each other and send messages using Apache Camel. The design constraints require me to create a framework such that all routing information, producers, consumers, endpoints etc should be a part of the camel-context.xml.
An individual should have the capability to modify such a file and completely change the existing route without having the Java code available to him.(The Java code would not be provided, only the compiled Jar would be)
For example in One setup,
Bean A ->Bean B->Bean C->file->email.
in another
Bean B->Bean A->Bean C->ftp->file->email
We have tried various approached, but if the originating bean is not implemented as a Java DSL, the messages rate is very high because camel constantly invokes Bean A in the first example and Bean B in the second(they being the source).
Bean A and Bean B originate messages and are event driven. In case the required event occurs, the beans send out a notification message.
My transformations are very simple and I do not require the power of Java DSL at all.
To summarize, I have the following questions:
1) Considering the above constraints, I do I ensure all routing information, including destination addresses, everything is a part of the camel context file?
2) Are there example I can look at for keeping the routing information completely independent of the java code?
3) How do I ensure Camel does not constantly invoke the originating bean?
4) Does Camel constantly invoke just the originating bean or any bean it sends & messages to irrespective of the position of the bean in the entire messaging queue?
I have run out of options trying various ways to set this up. Any help would be appreciated.
Read about hiding the middleware on the Camel wiki pages. This allows you to let clients use an interface to send/receive messages but totally unaware of Camel (no Camel API used at all).
Even better consider buying the Camel in Action book and read chapter 14 which talks about this.
http://www.manning.com/ibsen/
Save 41% on Manning books: Camel in Action or ActiveMQ in Action. Use code s2941. Expires 6th oct. http://www.manning.com/ibsen/
If you consider using ServiceMix of FuseESB, you might want to separate your routes in two parts.
First part would be the Event-driver bean that trigger the route. It could push messages to the ServiceNMR (see http://camel.apache.org/nmr.html).
The other part would be left to the framework users, using Spring DSL. It would just listen to message on the NMR (push by the other route) and do whatever they want with it.
Of course endpoint definition could be propertized using servicemix configuration service (see http://camel.apache.org/properties.html#Properties-UsingBlueprintpropertyplaceholderwithCamelroutes)