io.mongock.api.annotations

Annotation Type ChangeUnit

@Target(value=TYPE)
 @Retention(value=RUNTIME)
public @interface ChangeUnit

This annotation replaces the old annotation @ChangeLog(and changeSet).

The main difference is that classes annotated with @ChangeUnit can only have one changeSet method, annotated with @Execution and optionally another changeSet annotated with @BeforeExecution, which is run before the actual change is executed, this means, for example, that the method annotated with @BeforeExecution will be out of the native transaction linked to the changeLog, however, Mongock will try to revert the changes applied by the method @BeforeExecution by executing the method annotated with @RollbackBeforeExecution

The concept is basically the same, a class that wraps the logic of the migration

Classes annotated with @ChangeUnit must have the following: - One(and only one) one valid constructor annotated with @ChangeUnitConstructor(mandatory if more than one constructor exist after version 6) - One(and only one) method annotated with @Execution(mandatory) - One(and only one) method annotated with @RollbackExecution(mandatory) - At most, one method annotated with @BeforeExecution(optional) - If contains a method annotated with @BeforeExecution, one(and only one) method annotated with @RollbackBeforeExecution(mandatory if @BeforeExecution present)

Please follow one of the recommended approaches depending on your use case: - For existing changeLogs/changeSets created prior version 5: leave them untouched (use with the deprecated annotation)

- For new changeLogs/changeSets created from version 5: Annotated you class migration class with the annotation @ChangeUnit

See Also:

ChangeUnitConstructor, Execution, BeforeExecution, RollbackExecution, RollbackBeforeExecution

Required Element Summary

Required Elements

Modifier and Type	Required Element and Description
String	id Change unit's id.
String	order Sequence that provide correct order for change unit execution.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
String	author Author of the changeset.
boolean	failFast If true, will make the entire migration to break if the change unit produce an exception or the validation doesn't success.
boolean	runAlways Executes the change set on every Mongock's execution, even if it has been run before.
String	systemVersion Specifies the software systemVersion on which the change unit is to be applied.
boolean	transactional If true, Mongock will try to run the changeUnit in a native transaction, if possible.

Element Detail

id

public abstract String id

Change unit's id. It will be used to identify both change entries, the one linked to @Execution and @BeforeExecution(this one with the suffix `_before`) Obligatory.

Equivalent to field `id` in ChangeSet annotation

Returns:

Change unit's id

See Also:

ChangeSet

order

public abstract String order

Sequence that provide correct order for change unit execution. Sorted alphabetically, ascending. Obligatory.

Equivalent to field `order` in ChangeSet annotation and ChangeLog, as now there is only one "changeSet", annotated with @Execution

Returns:

Change unit's execution order

See Also:

ChangeSet

author

public abstract String author

Author of the changeset.

Equivalent to field `author` in ChangeSet annotation

Returns:

Change unit's author

See Also:

ChangeSet

Default:

""

failFast

public abstract boolean failFast

If true, will make the entire migration to break if the change unit produce an exception or the validation doesn't success. Migration will continue otherwise.

Equivalent to field `failFast` in ChangeSet annotation

Returns:

failFast

See Also:

ChangeSet

Default:

true

runAlways

public abstract boolean runAlways

Executes the change set on every Mongock's execution, even if it has been run before. Optional (default is false)

Equivalent to field `runAlways` in ChangeSet annotation

Returns:

should run always?

See Also:

ChangeSet

Default:

false

systemVersion

public abstract String systemVersion

Specifies the software systemVersion on which the change unit is to be applied. Optional (default is 0 and means all)

Equivalent to field `systemVersion` in ChangeSet annotation

Returns:

systemVersion

See Also:

ChangeSet

Default:

"0"

transactional

public abstract boolean transactional

If true, Mongock will try to run the changeUnit in a native transaction, if possible.

Returns:

If the changeUnit should be run in a native transaction.

Default:

true