topic Re: [resolved] How to retrieve datasource with it's JNDI name in Talend Route? in Talend Studio

[resolved] How to retrieve datasource with it's JNDI name in Talend Route?

Anonymous — Sat, 16 Nov 2024 10:47:21 GMT

Hi Team,
I am trying to retrieve all available data sources and their JNDI names in Talend Runtime. However, I only can get either all data sources or all JNDIs, but cannot map JNDIs to relavent data source instances.
For example, I managed to get all JNDIs and then try to get data sources with below code:

Registry reg = camelContext.getRegistry();
Set<org.apache.karaf.jndi.JndiService> s = reg.findByType(org.apache.karaf.jndi.JndiService.class);
if(s == null)
	System.out.println("JndiService is null");
else{
	for(org.apache.karaf.jndi.JndiService js : s)
	{
		try{
			Map<String, String> jndis = js.names();
			for(Map.Entry<String, String> row_jndi : jndis.entrySet() )
			{
				String key = row_jndi.getKey();
				String value = row_jndi.getValue();
				System.out.println("Key = " + key + "; Value = " + value);
				Object obj =  reg.lookupByName(key);
				if(obj != null)
					System.out.println("Obj is " + obj.toString());
				else
					System.out.println("Obj is null" ); 
			}
			
		}catch(Exception e)
		{
                   ....................
		}
	}
}

However, the reg.lookupByName(key) failed to get objects and log shows:

Key = osgi:service/WeChatDS; Value = org.apache.commons.dbcp2.managed.ManagedDataSource
Obj is null
Key = osgi:service/jndi; Value = org.apache.karaf.jndi.internal.JndiServiceImpl
Obj is null
Key = osgi:service/MobileCRMDS; Value = org.apache.commons.dbcp2.managed.ManagedDataSource
Obj is null
Key = osgi:service/jdbc/WeChat2; Value = org.postgresql.ds.PGPoolingDataSource
Obj is null

When I try to use code of: "Set<javax.sql.DataSource> o = reg.findByType(javax.sql.DataSource.class);", it only gives me instances of data sources, but I cannot use data source instance to fetch JNDI name.
Anyone could advice me how to get JNDI and relevant data source instance? BTW, I am working on TOS 6.0

Re: [resolved] How to retrieve datasource with it's JNDI name in Talend Route?

Anonymous — Fri, 19 Feb 2016 12:55:37 GMT

You could try to use plain jndi like:
Context context = new InitialContext();
and then use the context to look up and retrieve the DataSources.
Another option is to get hold of the OSGi BundleContext and lookup the DataSources as OSGi services.

Re: [resolved] How to retrieve datasource with it's JNDI name in Talend Route?

Anonymous — Fri, 19 Feb 2016 14:32:52 GMT

Hi Schneider,
Thank you for your reply. However, it throws exceptions as such:

javax.naming.NoInitialContextException: Need to specify class name in environment or system property, or as an applet parameter, or in an application resource file:  java.naming.factory.initial
        at javax.naming.spi.NamingManager.getInitialContext(Unknown Source)
        at javax.naming.InitialContext.getDefaultInitCtx(Unknown Source)
        at javax.naming.InitialContext.getURLOrDefaultInitCtx(Unknown Source)
        at javax.naming.InitialContext.lookup(Unknown Source)
        at test_datasource.mysqljob_0_1.mysqljob.tJava_1Process(mysqljob.java:737)
        at test_datasource.mysqljob_0_1.mysqljob.tPostgresqlConnection_1Process(mysqljob.java:663)
        at test_datasource.mysqljob_0_1.mysqljob.tPrejob_1Process(mysqljob.java:528)
        at test_datasource.mysqljob_0_1.mysqljob.runJobInTOS(mysqljob.java:2152)
        at org.talend.camel.TalendProducer.invokeTalendJob(TalendProducer.java:109)
        at org.talend.camel.TalendProducer.process(TalendProducer.java:65)
        at org.apache.camel.util.AsyncProcessorConverterHelper$ProcessorToAsyncProcessorBridge.process(AsyncProcessorConverterHelper.java:61)
        at org.apache.camel.processor.SendProcessor.process(SendProcessor.java:129)
        at org.apache.camel.management.InstrumentationProcessor.process(InstrumentationProcessor.java:77)
        at org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:448)
        at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:191)
        at org.apache.camel.processor.Pipeline.process(Pipeline.java:118)
        at org.apache.camel.processor.Pipeline.process(Pipeline.java:80)
        at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:191)
        at org.apache.camel.component.jetty.CamelContinuationServlet.service(CamelContinuationServlet.java:162)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:808)
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1669)
        at org.eclipse.jetty.servlets.MultiPartFilter.doFilter(MultiPartFilter.java:146)
        at org.apache.camel.component.jetty.CamelFilterWrapper.doFilter(CamelFilterWrapper.java:43)
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:221)
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
        at org.eclipse.jetty.server.Server.handle(Server.java:497)
        at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310)
        at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
        at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
        at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
        at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
        at java.lang.Thread.run(Unknown Source)

The codes are:

javax.naming.Context ctx = new javax.naming.InitialContext();
Object o = ctx.lookup("somename");

Am I using a wrong Context class? Context is unknown class in Talend....

Re: [resolved] How to retrieve datasource with it's JNDI name in Talend Route?

Anonymous — Fri, 19 Feb 2016 15:59:44 GMT

Finally, I managed to achieve my requirements using bundleContext...here are my codes in cConfig in Talend Route:

import org.osgi.framework.Bundle;
import org.osgi.framework.Constants;
import org.osgi.framework.ServiceReference;

Bundle[] bundles = bundleContext.getBundles();
for (Bundle bundle : bundles) {
	
	ServiceReference[] services = bundle.getRegisteredServices();
	if (services != null) {
		for (ServiceReference serviceReference : services) {
			String[] objectClasses = (String[])serviceReference.getProperty(Constants.OBJECTCLASS);
			boolean t = false;
			for(String s : objectClasses){
				if(s.equals("javax.sql.DataSource"))
				{
					t = true;
					break;
				}
			}
			if(t){
				Object actualService = bundleContext.getService(serviceReference);
				System.out.println("actualService is " + actualService);
				String jndiProperty = (String)serviceReference.getProperty("osgi.jndi.service.name");
				System.out.println("actualService JNDI is " + jndiProperty);				
			}
			
		}
	}
}

So actualService here refers to real data source and jndiProperty is its JNDI name.

Re: [resolved] How to retrieve datasource with it's JNDI name in Talend Route?

Anonymous — Sat, 20 Feb 2016 05:25:15 GMT

Resolved with walk around approach https://www.talendforge.org/forum/viewtopic.php?pid=178256#p178256