Spring-Boot Configuration for suppressing BatchDataInitializer - spring-batch

Question

I am using Spring-boot 0.5.0.M6 with Spring-Batch. Configuration has by using #EnableBatchProcessing with datasource etc configured in application.properties.
During first run of the application, everything works fine but after I stop the application and restart application, following error is seen
org.springframework.dao.DuplicateKeyException: PreparedStatementCallback; SQL [INSERT into BATCH_JOB_INSTANCE(JOB_INSTANCE_ID, JOB_NAME, JOB_KEY, VERSION) values (?, ?, ?, ?)]; Duplicate entry '1' for key 'PRIMARY'; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry '1' for key 'PRIMARY'
at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:239)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73)
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:659)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:908)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:969)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:974)
When digging down, i had observed following lines in logs
2013-12-06 12:12:37 INFO ResourceDatabasePopulator:162 - Executing SQL script from class path resource [org/springframework/batch/core/schema-mysql.sql]
2013-12-06 12:12:37 INFO ResourceDatabasePopulator:217 - Done executing SQL script from class path resource [org/springframework/batch/core/schema-mysql.sql] in 13 ms.
Root problem over here was schema-drop-mysql.sql was not triggered by schema-mysql.sql was triggered, thereby creating two entries in BATCH_JOB_SEQ.
For resolution of the same, I have added
#EnableAutoConfiguration(exclude={BatchAutoConfiguration.class})
However due to this I need to execute schema-mysql.sql explicitly, which as of now is ok, but would be problem when spring-batch version would be updated with updates in schema
Hence have couple of questions:
1. How to autoconfigure batch for even executing schema-drop-mysql.sql before schema-mysql.sql?
2. is there way to configure this BatchDatabaseInitializer to run kind of "update" mode?
Regards

Answer 1

With the current version of Spring Batch autoconfiguration that isn't possible with the upcoming version it is possible to disable the automatic creation of the database tables by specifying the spring.batch.initializer.enabled property and setting it to false.
IMHO you shouldn't use the automatic creation/update features to create schema's either do it yourself or use tools like LiquiBase or FlyWay to do it more controlled.
Also see https://stackoverflow.com/questions/8418814/db-migration-tool-liquibase-or-flyway
You can always execute the schema-drop-mysql.sql yourself, as a work around you could add a #PreDestroy method to your #Configuration class which executes this script. (Maybe you could even add this to an #Configuration class which is enabled only in dev mode/profile).