topic Re: Close anSSH tunnel connection in Talend Studio

Close anSSH tunnel connection

Anonymous — Sat, 16 Nov 2024 10:44:24 GMT

Hi,
currently we work on the exchange component tSshTunnel to open a tunnel with a forwarding port (L string) to secure a non secure data base.(SSL solution is not possible).
It works fine one shot but the tunnel keep open during a few minutes (15-30) and I can't reopen the same ssh tunnel forwarding: I can't serialize job execution, and more not paralyze.
The tSshTunnel use the librairy Jsch. It creates a connection session. It applies connect() to open the tunnel but don't close them at the end of component use with disconnect().
I'm not java developer but how can I use the disconnect() method to the session object creates in the component ?
Other method to close is to identify the process ID and kill them.
Regards
Jeremie

---------------------------------------------------------------------
JAVA code component bloc in the job

public void tSshTunnel_1Process(
			final java.util.Map<String, Object> globalMap)
			throws TalendException {
		globalMap.put("tSshTunnel_1_SUBPROCESS_STATE", 0);
		final boolean execStat = this.execStat;
		String iterateId = "";
		String currentComponent = "";
		java.util.Map<String, Object> resourceMap = new java.util.HashMap<String, Object>();
		try {
			String currentMethodName = new java.lang.Exception()
					.getStackTrace().getMethodName();
			boolean resumeIt = currentMethodName.equals(resumeEntryMethodName);
			if (resumeEntryMethodName == null || resumeIt || globalResumeTicket) {// start
																					// the
																					// resume
				globalResumeTicket = true;
				/**
				 *  start
				 */
				ok_Hash.put("tSshTunnel_1", false);
				start_Hash.put("tSshTunnel_1", System.currentTimeMillis());
				currentComponent = "tSshTunnel_1";
				int tos_count_tSshTunnel_1 = 0;
				java.util.Hashtable<String, com.jcraft.jsch.Session> tunnels_tSshTunnel_1 = new java.util.Hashtable<String, com.jcraft.jsch.Session>();
				boolean useKey_tSshTunnel_1_0 = false;
				if (!((String) globalMap.get("tCreateTemporaryFile_1_FILEPATH"))
						.equals(""))
					useKey_tSshTunnel_1_0 = true;
				if (!tunnels_tSshTunnel_1
						.containsKey(context.connection_sshtunnel_username
								+ "@" + context.connection_sshtunnel_hostname
								+ ":" + context.connection_sshtunnel_port)) {
					com.jcraft.jsch.JSch j = new com.jcraft.jsch.JSch();
					if (useKey_tSshTunnel_1_0)
						j.addIdentity(((String) globalMap
								.get("tCreateTemporaryFile_1_FILEPATH")));
					com.jcraft.jsch.Session session = j
							.getSession(
									context.connection_sshtunnel_username,
									context.connection_sshtunnel_hostname,
									Integer.parseInt(context.connection_sshtunnel_port));
					java.util.Hashtable<String, String> config = new java.util.Hashtable<String, String>();
					config.put("StrictHostKeyChecking", "no");
					session.setConfig(config);
					if (!useKey_tSshTunnel_1_0) {
						session.setPassword(context.connection_sshtunnel_password);
					}
					session.connect();
					String[] credentials = context.connection_sshtunnel_ltunnelstring
							.split(":");
					session.setPortForwardingL(
							Integer.parseInt(credentials), credentials,
							Integer.parseInt(credentials));
					tunnels_tSshTunnel_1.put(
							context.connection_sshtunnel_username + "@"
									+ context.connection_sshtunnel_hostname
									+ ":" + context.connection_sshtunnel_port,
							session);
				} else {
					com.jcraft.jsch.Session session = tunnels_tSshTunnel_1
							.get(context.connection_sshtunnel_username + "@"
									+ context.connection_sshtunnel_hostname
									+ ":" + context.connection_sshtunnel_port);
					String[] credentials = context.connection_sshtunnel_ltunnelstring
							.split(":");
					session.setPortForwardingL(
							Integer.parseInt(credentials), credentials,
							Integer.parseInt(credentials));
				}
				globalMap.put("tunnels_tSshTunnel_1", tunnels_tSshTunnel_1);
				/**
				 *  stop
				 */
				/**
				 *  start
				 */
				currentComponent = "tSshTunnel_1";
				tos_count_tSshTunnel_1++;
				/**
				 *  stop
				 */
				/**
				 *  start
				 */
				currentComponent = "tSshTunnel_1";
				ok_Hash.put("tSshTunnel_1", true);
				end_Hash.put("tSshTunnel_1", System.currentTimeMillis());
				tSystem_1Process(globalMap);
				/**
				 *  stop
				 */
			}// end the resume
		} catch (java.lang.Exception e) {
			if (!(e instanceof TalendException)) {
				log.fatal(currentComponent + " " + e.getMessage());
			}
			TalendException te = new TalendException(e, currentComponent,
					globalMap);
			throw te;
		} catch (java.lang.Error error) {
			throw error;
		} finally {
			try {
				/**
				 *  start
				 */
				currentComponent = "tSshTunnel_1";
				/**
				 *  stop
				 */
			} catch (java.lang.Exception e) {
				// ignore
			} catch (java.lang.Error error) {
				// ignore
			}
			resourceMap = null;
		}
		globalMap.put("tSshTunnel_1_SUBPROCESS_STATE", 1);
	}

Re: Close anSSH tunnel connection

Anonymous — Tue, 15 Mar 2016 05:39:47 GMT

Are you using the component from exchange:
https://exchange.talend.com/#marketplaceproductoverview:gallery=marketplace%252F1&pi=marketplace%252F1%252Fproducts%252F678%252Fitems%252F987
Thomas

Re: Close anSSH tunnel connection

Anonymous — Tue, 15 Mar 2016 08:40:15 GMT

Hi Jeremie
I think you should close the session after the component, for example:
tSSHTunnel
|
onsubjobok
|
do your business
|
tJava
on tJava, close the session.


com.jcraft.jsch.Session session=(com.jcraft.jsch.Session)globalMap.get("session");
session.disconnect();

In order to get the session on another component, you need to modify the source file of component, open the tSshTunnel_begin.javajet file and edit it as below:

<%@ jet 
imports="
    	org.talend.core.model.process.INode    
		org.talend.designer.codegen.config.CodeGeneratorArgument
		org.talend.core.model.process.ElementParameterParser 
		java.util.List
		java.util.Map
		" 
%>
<%
	CodeGeneratorArgument codeGenArgument = (CodeGeneratorArgument) argument;
	INode node = (INode)codeGenArgument.getArgument();
	String cid = node.getUniqueName();
	List<Map<String, String>> lines = (List<Map<String, String>>)ElementParameterParser.getObjectValue(node, "__TUNNELS__");
	
%> 
    com.jcraft.jsch.Session session;
	java.util.Hashtable<String,com.jcraft.jsch.Session> tunnels_<%=cid %> = new java.util.Hashtable<String,com.jcraft.jsch.Session>();
<%
  for (int i=0; i<lines.size(); i++) {
    Map<String, String> line = lines.get(i);
    
%>
	boolean useKey_<%=cid %>_<%=i%>=false;
	if (!<%=line.get("KEYFILE")%>.equals(""))
		useKey_<%=cid %>_<%=i%>=true;
		
	if (!tunnels_<%=cid %>.containsKey(<%=line.get("USERNAME")%>+"@"+<%=line.get("HOST")%>+":"+<%=line.get("PORT")%>)) {
		com.jcraft.jsch.JSch j=new com.jcraft.jsch.JSch();
		if(useKey_<%=cid %>_<%=i%>)
			j.addIdentity(<%=line.get("KEYFILE")%>);
	   session=j.getSession(<%=line.get("USERNAME")%>,<%=line.get("HOST")%>,Integer.parseInt(<%=line.get("PORT")%>));
		java.util.Hashtable<String, String> config = new java.util.Hashtable<String, String>();
		config.put("StrictHostKeyChecking", "no");
		session.setConfig(config);
		if (!useKey_<%=cid %>_<%=i%>) {
			session.setPassword(<%=line.get("PASSWORD")%>);
		}
		session.connect();
		String[] credentials = <%=line.get("L_TUNNEL_STRING")%>.split(":");
		session.setPortForwardingL(Integer.parseInt(credentials), credentials, Integer.parseInt(credentials));
		tunnels_<%=cid %>.put(<%=line.get("USERNAME")%>+"@"+<%=line.get("HOST")%>+":"+<%=line.get("PORT")%>,session);
		
	} else {
	    session = tunnels_<%=cid %>.get(<%=line.get("USERNAME")%>+"@"+<%=line.get("HOST")%>+":"+<%=line.get("PORT")%>);
		String[] credentials = <%=line.get("L_TUNNEL_STRING")%>.split(":");
		session.setPortForwardingL(Integer.parseInt(credentials), credentials, Integer.parseInt(credentials));
	}
	globalMap.put("session",session);
	globalMap.put("tunnels_<%=cid %>",tunnels_<%=cid %>);
<%
  }
%>

Regards
Shong

Re: Close anSSH tunnel connection

Anonymous — Tue, 15 Mar 2016 13:43:50 GMT

Hi,
I use the component on Talend Exchange
thanks for all information and code, I have test them with succeed.
I think I can include the java code in the tSshTunnel_end.javajet ?
Best regards
Jeremie

Re: Close anSSH tunnel connection

Anonymous — Tue, 15 Mar 2016 14:35:30 GMT

Hi
The session should be closed after your business processing, so you can create a new component such as tSSHClose to close the session, such as tMysqlClose.

Re: Close anSSH tunnel connection

Anonymous — Tue, 15 Mar 2016 17:49:32 GMT

Thanks
Jeremie