Do not update the externalExecutionId if null when starting TaskExecution

resolves #271

spring-cloud-task-core/src/main/java/org/springframework/cloud/task/repository/dao/JdbcTaskExecutionDao.java

@@ -78,10 +78,13 @@ public class JdbcTaskExecutionDao implements TaskExecutionDao {
 	private static final String CREATE_TASK_ARGUMENT = "INSERT into "
 			+ "%PREFIX%EXECUTION_PARAMS(TASK_EXECUTION_ID, TASK_PARAM ) values (?, ?)";
 
-	private static final String START_TASK_EXECUTION = "UPDATE %PREFIX%EXECUTION set "
-			+ "START_TIME = ?, TASK_NAME = ?, LAST_UPDATED = ?, "
-			+ "EXTERNAL_EXECUTION_ID = ?, PARENT_EXECUTION_ID = ? "
-			+ "where TASK_EXECUTION_ID = ?";
+	private static final String START_TASK_EXECUTION_PREFIX = "UPDATE %PREFIX%EXECUTION set "
+			+ "START_TIME = ?, TASK_NAME = ?, LAST_UPDATED = ?";
+
+	private static final String START_TASK_EXECUTION_EXTERNAL_ID_SUFFIX = ", "
+			+ "EXTERNAL_EXECUTION_ID = ?, PARENT_EXECUTION_ID = ? where TASK_EXECUTION_ID = ?";
+
+	private static final String START_TASK_EXECUTION_SUFFIX = ", PARENT_EXECUTION_ID = ? where TASK_EXECUTION_ID = ?";
 
 	private static final String CHECK_TASK_EXECUTION_EXISTS = "SELECT COUNT(*) FROM "
 			+ "%PREFIX%EXECUTION WHERE TASK_EXECUTION_ID = ?";
@@ -180,7 +183,8 @@ public class JdbcTaskExecutionDao implements TaskExecutionDao {
 	}
 
 	@Override
-	public TaskExecution startTaskExecution(long executionId, String taskName, Date startTime, List<String> arguments,
+	public TaskExecution startTaskExecution(long executionId, String taskName,
+			Date startTime, List<String> arguments,
 			String externalExecutionId) {
 		return startTaskExecution(executionId, taskName, startTime, arguments,
 				externalExecutionId, null);
@@ -192,15 +196,25 @@ public class JdbcTaskExecutionDao implements TaskExecutionDao {
 			String externalExecutionId, Long parentExecutionId) {
 		TaskExecution taskExecution = new TaskExecution(executionId, null, taskName,
 				startTime, null, null, arguments,null, externalExecutionId, parentExecutionId);
+		Object[] queryParameters;
+		int[] argTypes;
+		String updateString = START_TASK_EXECUTION_PREFIX;
+		if(externalExecutionId == null) {
+			queryParameters = new Object[]{startTime, taskName,
+					new Date(), parentExecutionId, executionId};
+			updateString += START_TASK_EXECUTION_SUFFIX;
+			argTypes = new int[]{Types.TIMESTAMP, Types.VARCHAR,
+					Types.TIMESTAMP, Types.BIGINT, Types.BIGINT};
+		}
+		else {
+			queryParameters = new Object[]{ startTime, taskName,
+					new Date(), externalExecutionId, parentExecutionId, executionId};
+			argTypes = new int[]{ Types.TIMESTAMP, Types.VARCHAR,
+					Types.TIMESTAMP, Types.VARCHAR, Types.BIGINT, Types.BIGINT };
+			updateString += START_TASK_EXECUTION_EXTERNAL_ID_SUFFIX;
+		}
 
-		Object[] queryParameters = new Object[]{ startTime, taskName,
-				new Date(), externalExecutionId,
-				parentExecutionId, executionId};
-		jdbcTemplate.update(
-				getQuery(START_TASK_EXECUTION),
-				queryParameters,
-				new int[]{ Types.TIMESTAMP, Types.VARCHAR,  Types.TIMESTAMP,
-						Types.VARCHAR, Types.BIGINT, Types.BIGINT });
+		jdbcTemplate.update(getQuery(updateString), queryParameters, argTypes);
 		insertTaskArguments(executionId, arguments);
 		return taskExecution;
 	}

spring-cloud-task-core/src/main/java/org/springframework/cloud/task/repository/dao/MapTaskExecutionDao.java

@@ -83,9 +83,10 @@ public class MapTaskExecutionDao implements TaskExecutionDao {
 		taskExecution.setTaskName(taskName);
 		taskExecution.setStartTime(startTime);
 		taskExecution.setArguments(arguments);
-		taskExecution.setExternalExecutionId(externalExecutionid);
 		taskExecution.setParentExecutionId(parentExecutionId);
-
+		if(externalExecutionid != null) {
+			taskExecution.setExternalExecutionId(externalExecutionid);
+		}
 		return taskExecution;
 	}
 

spring-cloud-task-core/src/test/java/org/springframework/cloud/task/repository/dao/JdbcTaskExecutionDaoTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -166,6 +166,40 @@ public class JdbcTaskExecutionDaoTests {
 		assertEquals("FOO3", taskExecution.getTaskName());
 	}
 
+	@Test
+	@DirtiesContext
+	public void testStartExecutionWithNullExternalExecutionIdExisting() {
+		TaskExecution expectedTaskExecution =
+				initializeTaskExecutionWithExternalExecutionId();
+
+		dao.startTaskExecution(expectedTaskExecution.getExecutionId(), expectedTaskExecution.getTaskName(),
+				expectedTaskExecution.getStartTime(), expectedTaskExecution.getArguments(),
+				null);
+		TestVerifierUtils.verifyTaskExecution(expectedTaskExecution,
+				TestDBUtils.getTaskExecutionFromDB(dataSource, expectedTaskExecution.getExecutionId()));
+	}
+
+	@Test
+	@DirtiesContext
+	public void testStartExecutionWithNullExternalExecutionIdNonExisting() {
+		TaskExecution expectedTaskExecution =
+				initializeTaskExecutionWithExternalExecutionId();
+
+		dao.startTaskExecution(expectedTaskExecution.getExecutionId(), expectedTaskExecution.getTaskName(),
+				expectedTaskExecution.getStartTime(), expectedTaskExecution.getArguments(),
+				"BAR");
+		expectedTaskExecution.setExternalExecutionId("BAR");
+		TestVerifierUtils.verifyTaskExecution(expectedTaskExecution,
+				TestDBUtils.getTaskExecutionFromDB(dataSource, expectedTaskExecution.getExecutionId()));
+	}
+
+	private TaskExecution initializeTaskExecutionWithExternalExecutionId() {
+		TaskExecution expectedTaskExecution = TestVerifierUtils.createSampleTaskExecutionNoArg();
+		return this.dao.createTaskExecution(expectedTaskExecution.getTaskName(),
+				expectedTaskExecution.getStartTime(), expectedTaskExecution.getArguments(),
+				"FOO1");
+	}
+
 	private Iterator<TaskExecution> getPageIterator(int pageNum, int pageSize, Sort sort) {
 		Pageable pageable = (sort == null) ?
 				new PageRequest(pageNum, pageSize) :

spring-cloud-task-core/src/test/java/org/springframework/cloud/task/repository/dao/MapTaskExecutionDaoTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -137,4 +137,34 @@ public class MapTaskExecutionDaoTests {
 		assertNull(this.dao.getTaskExecutionIdByJobExecutionId(789L));
 	}
 
+	@Test
+	public void testStartExecutionWithNullExternalExecutionIdExisting(){
+		TaskExecution expectedTaskExecution =
+				initializeTaskExecutionWithExternalExecutionId();
+		Map<Long, TaskExecution> taskExecutionMap = this.dao.getTaskExecutions();
+		this.dao.startTaskExecution(expectedTaskExecution.getExecutionId(), expectedTaskExecution.getTaskName(),
+				expectedTaskExecution.getStartTime(), expectedTaskExecution.getArguments(),
+				null);
+		TestVerifierUtils.verifyTaskExecution(expectedTaskExecution,
+				taskExecutionMap.get(expectedTaskExecution.getExecutionId()));
+	}
+
+	@Test
+	public void testStartExecutionWithNullExternalExecutionIdNonExisting(){
+		TaskExecution expectedTaskExecution =
+				initializeTaskExecutionWithExternalExecutionId();
+		Map<Long, TaskExecution> taskExecutionMap = this.dao.getTaskExecutions();
+		this.dao.startTaskExecution(expectedTaskExecution.getExecutionId(), expectedTaskExecution.getTaskName(),
+				expectedTaskExecution.getStartTime(), expectedTaskExecution.getArguments(),
+				"BAR");
+		TestVerifierUtils.verifyTaskExecution(expectedTaskExecution,
+				taskExecutionMap.get(expectedTaskExecution.getExecutionId()));
+	}
+
+	private TaskExecution initializeTaskExecutionWithExternalExecutionId() {
+		TaskExecution expectedTaskExecution = TestVerifierUtils.createSampleTaskExecutionNoArg();
+		return this.dao.createTaskExecution(expectedTaskExecution.getTaskName(),
+				expectedTaskExecution.getStartTime(), expectedTaskExecution.getArguments(),
+				"FOO1");
+	}
 }