Spring Integration for SFTP giving Private Key Error - spring-boot

Question

I am trying to do a file upload using Spring Integration and i am stuck at the below error. My Private keys are perfectly fine though. What can be the problem area in this case?
If I run the sftp -i .....command with the same private key it works
I have defined a rest controller which invokes the gateway
gateway.uploadFile(file);
The Upload Config is as simple as this
#Bean
public DefaultSftpSessionFactory gimmeFactory(){
DefaultSftpSessionFactory factory = new DefaultSftpSessionFactory(true);
factory.setHost(sftpHost);
factory.setPort(sftpPort);
factory.setUser(sftpUser);
if (sftpPrivateKey != null) {
factory.setPrivateKey(sftpPrivateKey);
// factory.setPrivateKeyPassphrase(sftpPrivateKeyPassphrase);
} else {
factory.setPassword(sftpPasword);
}
factory.setAllowUnknownKeys(true);
return (factory);
}
#Bean
#ServiceActivator(inputChannel = "uploadfile")
MessageHandler uploadHandler(DefaultSftpSessionFactory factory){
SftpMessageHandler messageHandler = new SftpMessageHandler(factory);
messageHandler.setRemoteDirectoryExpression(new LiteralExpression("/upload/topsecret"));
messageHandler.setFileNameGenerator(message -> String.format("mytextfile_%s.txt", LocalDateTime.now()));
return messageHandler;
}
The Exception i get is below
java.lang.IllegalStateException: failed to create SFTP Session
at org.springframework.integration.sftp.session.DefaultSftpSessionFactory.getSession(DefaultSftpSessionFactory.java:391)
at org.springframework.integration.sftp.session.DefaultSftpSessionFactory.getSession(DefaultSftpSessionFactory.java:60)
at org.springframework.integration.file.remote.RemoteFileTemplate.execute(RemoteFileTemplate.java:432)
at org.springframework.integration.file.remote.RemoteFileTemplate.send(RemoteFileTemplate.java:298)
at org.springframework.integration.file.remote.RemoteFileTemplate.send(RemoteFileTemplate.java:286)
at org.springframework.integration.file.remote.RemoteFileTemplate.send(RemoteFileTemplate.java:278)
at org.springframework.integration.file.remote.handler.FileTransferringMessageHandler.handleMessageInternal(FileTransferringMessageHandler.java:205)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:170)
at org.springframework.integration.handler.ReplyProducingMessageHandlerWrapper.handleRequestMessage(ReplyProducingMessageHandlerWrapper.java:49)
at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:127)
at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:170)
at org.springframework.integration.dispatcher.AbstractDispatcher.tryOptimizedDispatch(AbstractDispatcher.java:115)
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:133)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:106)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:73)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:453)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:403)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:187)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:166)
at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:47)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:109)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.convertAndSend(AbstractMessageSendingTemplate.java:151)
at org.springframework.messaging.core.AbstractMessageSendingTemplate.convertAndSend(AbstractMessageSendingTemplate.java:143)
at org.springframework.integration.gateway.MessagingGatewaySupport.send(MessagingGatewaySupport.java:429)
at org.springframework.integration.gateway.GatewayProxyFactoryBean.sendOrSendAndReceive(GatewayProxyFactoryBean.java:568)
at org.springframework.integration.gateway.GatewayProxyFactoryBean.invokeGatewayMethod(GatewayProxyFactoryBean.java:489)
at org.springframework.integration.gateway.GatewayProxyFactoryBean.doInvoke(GatewayProxyFactoryBean.java:464)
at org.springframework.integration.gateway.GatewayProxyFactoryBean.invoke(GatewayProxyFactoryBean.java:453)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212)
at com.sun.proxy.$Proxy72.uploadFile(Unknown Source)
at edu.aus.finance.hsbc.approach2.UploadRestController.uploadFile(UploadRestController.java:39)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:367)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1639)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)
Caused by: com.jcraft.jsch.JSchException: invalid privatekey: [B#635e925d
at com.jcraft.jsch.KeyPair.load(KeyPair.java:664)
at com.jcraft.jsch.IdentityFile.newInstance(IdentityFile.java:46)
at com.jcraft.jsch.JSch.addIdentity(JSch.java:441)
at org.springframework.integration.sftp.session.DefaultSftpSessionFactory.initJschSession(DefaultSftpSessionFactory.java:423)
at org.springframework.integration.sftp.session.DefaultSftpSessionFactory.getSession(DefaultSftpSessionFactory.java:379)
... 81 more

Answer 1

Yo need to load the resourse on the factory.setPrivateKey(privateKey);
Resource resource = resourceLoader.getResource("file:" + sftpPrivateKey);
factory.setPrivateKey(resource);