JDBC Protocol Handler (jdbc://)

Owned by Bharath kumar A (Unlicensed)
Last updated: Feb 12, 2019

A-Stack supports JDBC protocol Handler, that can be used to retrieve records from various relational databases using JDBC interface. 

JDBC Protocol Handler Flow:

JDBC Protocol Handler Installation: 


DateDownload LocationVersion
1/30/2019

sff.bundle.ext.jdbc-1.0.0.zip

1.0.0


JDBC  Setup Instructions

  1. Unzip the downloaded zip file
  2. Copy the following jar files from this location to the sff.auto.launch folder which is present in your A-Stack Prime folder.
    1. org.osgi.service.jdbc-1.0.0.jar
    2. sff.bundle.ext.jdbc-1.0.0.jar
  3. In addition to the above bundles, we need to copy the JDBC driver jar file (OSGI bundle) for the selected database. You can refer the below repository to get OSGi version of database server.


Change Log

  • Version 1.0.0
  1. All CRUD operations can be executed on Relational database using JDBC handler
  2. Connection pooling support using HikariCP connection pool library.


JDBC Protocol Parameters:

  1. The table below lists all the parameters of Mqtt protocol handler and their description

Parameter Name

Parameter Description

QueryString


Select query to retrieve records from the database.


Usage of JDBC protocol handler:

Invoke JDBC handler with selection query

Trigger JDBC Invoke Action
<ThingModel Name="User">
					<Sid name="sysId" />
					<String Name="userId" KnownBy="JDBCInvokeAction" />
					<String Name="password" />
					<Action Name="JDBCInvokeAction" Documentation="Invooke JDBC Protocol Handler">
						<Workflow Limit="1" Live="1" Timeout="-1">
							<Task name="Main" while="true">
								<Event name="Argument" as="ActionArgument" />
								<Log Level="INFO" Message="***** Before Invoke *****"  waitFor="Argument"/>
								<Invoke name="InvokeJDBC" waitFor="Argument" Post="jdbc://?JdbcDriverClass=org.h2.Driver;url=jdbc:h2:tcp://localhost/~/employee;user=sa;password=;" scope="Local">
									<Message type="text" xmlns="foo">
										<Value>
											<QueryString operation="Select" limit="2">
												select * from emp
											</QueryString>
										</Value>
									</Message>
								</Invoke>							
								<Log Level="INFO" Message="Total [:Invoke.InvokeJDBC.Message.Value:]" />

								<Output name="Result" as="ActionResult">
									<Value>										
										<userId>[:Event.Argument.userId.Value:]
										</userId>
									</Value>
								</Output>
							</Task>
						</Workflow>
					</Action>
				</ThingModel>
Trigger JDBC Invoke Action
<Query>
	<Create>
		<User>
			<userId>userid123</userId>
			<password>pwd123</password>
		</User>
	</Create>
</Query>
JDBC Successful output format - Select Operation: The output message of jdbc handler is an xml structure that has fields of database columns which are retrieved using Select operation.
JDBC Handler successful response
<Result StatusCode="200" Description="Successful.">
  <Records>
    <Record>
      <EMPNO>7839</EMPNO>
      <ENAME>King</ENAME>
      <JOB>President</JOB>
      <MGR/>
      <HIREDATE>1981-11-17</HIREDATE>
      <SAL>7698</SAL>
      <COMM/>
      <DEPTNO>10</DEPTNO>
    </Record>
    <Record>
      <EMPNO>7698</EMPNO>
      <ENAME>Blake</ENAME>
      <JOB>Manager</JOB>
      <MGR>7839</MGR>
      <HIREDATE>1981-05-01</HIREDATE>
      <SAL>7782</SAL>
      <COMM/>
      <DEPTNO>20</DEPTNO>
    </Record>
    
  </Records>
</Result>


JDBC Successful response format - Inserrt, Update,Delete operations: The output message of jdbc handler is an xml structure that has fields of database columns which are retrieved using Insert,Update,Delete query operations.

Response for update operaton
<Result StatusCode="200" Description="Successful.">
<Records>
<RowsAffected>1</RowsAffected>
</Records>
</Result>

JDBC handler failure/error response

JDBC Failure Response
<Result StatusCode="502" Description="Exception occured during JDBC Invocation.">
<Error>Error while executing the jdbc query org.h2.jdbc.JdbcSQLException: Connection is broken: "java.net.ConnectException: Connection refused: connect: localhost" [90067-197]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:357)
at org.h2.message.DbException.get(DbException.java:168)
at org.h2.engine.SessionRemote.connectServer(SessionRemote.java:451)
at org.h2.engine.SessionRemote.connectEmbeddedOrServer(SessionRemote.java:332)
at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:124)
at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:103)
at org.h2.Driver.connect(Driver.java:69)
at org.h2.jdbcx.JdbcDataSource.getJdbcConnection(JdbcDataSource.java:189)
at org.h2.jdbcx.JdbcDataSource.getConnection(JdbcDataSource.java:178)
at com.atomiton.sff.imp.jdbc.QueryExecutor.executeSelectStatment(QueryExecutor.java:80)
at com.atomiton.sff.imp.netty.jdbc.DatabaseInvocationHandler.messageReceived(DatabaseInvocationHandler.java:59)
at org.jboss.netty.channel.SimpleChannelHandler.handleUpstream(SimpleChannelHandler.java:88)
at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
at org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791)
at org.jboss.netty.handler.execution.ChannelUpstreamEventRunnable.doRun(ChannelUpstreamEventRunnable.java:43)
at org.jboss.netty.handler.execution.ChannelEventRunnable.run(ChannelEventRunnable.java:67)
at org.jboss.netty.handler.execution.OrderedMemoryAwareThreadPoolExecutor$ChildExecutor.run(OrderedMemoryAwareThreadPoolExecutor.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at org.h2.util.NetUtils.createSocket(NetUtils.java:103)
at org.h2.util.NetUtils.createSocket(NetUtils.java:83)
at org.h2.engine.SessionRemote.initTransfer(SessionRemote.java:114)
at org.h2.engine.SessionRemote.connectServer(SessionRemote.java:447)
... 17 more
</Error>
</Result>