HHH-11886 - Elaborate Envers documentation and switch to actual source code examples

Move code snippets to actual test cases for queries using modified flags
This commit is contained in:
Vlad Mihalcea 2017-08-31 17:12:49 +03:00
parent e7c239d57f
commit c25a859ade
5 changed files with 400 additions and 30 deletions

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@ -619,7 +619,7 @@ Sometimes it is useful to store additional metadata for each revision, when you
The feature described in <<envers-tracking-modified-entities-revchanges>> makes it possible to tell which entities were modified in a given revision.
The feature described here takes it one step further.
"Modification Flags" enable Envers to track which properties of audited entities were modified in a given revision.
_Modification Flags_ enable Envers to track which properties of audited entities were modified in a given revision.
Tracking entity changes at property level can be enabled by:
@ -854,48 +854,77 @@ in which the entity was deleted should be included in the results.
If yes, such entities will have the revision type `DEL` and all attributes, except the `id`, will be set to `null`.
[[envers-tracking-properties-changes-queries]]
=== Querying for revisions of entity that modified given property
=== Querying for revisions of entity that modified a given property
For the two types of queries described above it's possible to use special `Audit` criteria called `hasChanged()` and `hasNotChanged()`
that makes use of the functionality described in <<envers-tracking-properties-changes>>.
They're best suited for vertical queries, however existing API doesn't restrict their usage for horizontal ones.
Let's have a look at following examples:
Let's have a look at various queries that can benefit from these two criteria.
[source,java]
First, you must make sure that your entity can track _modification flags_:
[[envers-tracking-properties-changes-queries-entity-example]]
.Valid only when audit logging tracks entity attribute modification flags
====
[source, JAVA, indent=0]
----
AuditQuery query = getAuditReader().createQuery()
.forRevisionsOfEntity( MyEntity.class, false, true )
.add( AuditEntity.id().eq( id ) );
.add( AuditEntity.property( "actualDate" ).hasChanged() );
include::{sourcedir}/QueryAuditWithModifiedFlagTest.java[tags=envers-tracking-properties-changes-queries-entity-example]
----
====
The following query will return all revisions of the `Customer` entity with the given `id`,
for which the `lastName` property has changed.
[[envers-tracking-properties-changes-queries-hasChanged-example]]
.Getting all `Customer` revisions for which the `lastName` attribute has changed
====
[source, JAVA, indent=0]
----
include::{sourcedir}/QueryAuditWithModifiedFlagTest.java[tags=envers-tracking-properties-changes-queries-hasChanged-example]
----
This query will return all revisions of `MyEntity` with given `id`, where the `actualDate` property has been changed.
Using this query we won't get all other revisions in which `actualDate` wasn't touched.
Of course, nothing prevents user from combining `hasChanged` condition with some additional criteria - add method can be used here in a normal way.
[source,java]
[source, SQL, indent=0]
----
AuditQuery query = getAuditReader().createQuery()
.forEntitiesAtRevision( MyEntity.class, revisionNumber )
.add( AuditEntity.property( "prop1" ).hasChanged() )
.add( AuditEntity.property( "prop2" ).hasNotChanged() );
include::{extrasdir}/envers-tracking-properties-changes-queries-hasChanged-example.sql[]
----
====
Using this query we won't get all other revisions in which `lastName` wasn't touched.
From the SQL query you can see that the `lastName_MOD` column is being used in the WHERE clause,
hence the aforementioned requirement for tracking modification flags.
Of course, nothing prevents user from combining `hasChanged` condition with some additional criteria.
[[envers-tracking-properties-changes-queries-hasChanged-and-hasNotChanged-example]]
.Getting all `Customer` revisions for which the `lastName` attribute has changed and the `firstName` attribute has not changed
====
[source, JAVA, indent=0]
----
include::{sourcedir}/QueryAuditWithModifiedFlagTest.java[tags=envers-tracking-properties-changes-queries-hasChanged-and-hasNotChanged-example]
----
This query will return horizontal slice for `MyEntity` at the time `revisionNumber` was generated.
It will be limited to revisions that modified `prop1` but not `prop2`.
Note that the result set will usually also contain revisions with numbers lower than the `revisionNumber`,
so wem cannot read this query as "Give me all MyEntities changed in `revisionNumber` with `prop1` modified and `prop2` untouched".
To get such result we have to use the `forEntitiesModifiedAtRevision` query:
[source,java]
[source, SQL, indent=0]
----
AuditQuery query = getAuditReader().createQuery()
.forEntitiesModifiedAtRevision( MyEntity.class, revisionNumber )
.add( AuditEntity.property( "prop1" ).hasChanged() )
.add( AuditEntity.property( "prop2" ).hasNotChanged() );
include::{extrasdir}/envers-tracking-properties-changes-queries-hasChanged-and-hasNotChanged-example.sql[]
----
====
To get the `Customer` entities changed at a given `revisionNumber` with `lastName` modified and `firstName` untouched,
we have to use the `forEntitiesModifiedAtRevision` query:
[[envers-tracking-properties-changes-queries-at-revision-example]]
.Getting the `Customer` entity for a given revision if the `lastName` attribute has changed and the `firstName` attribute has not changed
====
[source, JAVA, indent=0]
----
include::{sourcedir}/QueryAuditWithModifiedFlagTest.java[tags=envers-tracking-properties-changes-queries-at-revision-example]
----
[source, SQL, indent=0]
----
include::{extrasdir}/envers-tracking-properties-changes-queries-at-revision-example.sql[]
----
====
[[envers-tracking-modified-entities-queries]]
=== Querying for entities modified in a given revision

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@ -0,0 +1,25 @@
select
queryaudit0_.id as id1_3_,
queryaudit0_.REV as REV2_3_,
queryaudit0_.REVTYPE as REVTYPE3_3_,
queryaudit0_.REVEND as REVEND4_3_,
queryaudit0_.created_on as created_5_3_,
queryaudit0_.createdOn_MOD as createdO6_3_,
queryaudit0_.firstName as firstNam7_3_,
queryaudit0_.firstName_MOD as firstNam8_3_,
queryaudit0_.lastName as lastName9_3_,
queryaudit0_.lastName_MOD as lastNam10_3_,
queryaudit0_.address_id as address11_3_,
queryaudit0_.address_MOD as address12_3_
from
Customer_AUD queryaudit0_
where
queryaudit0_.REV=?
and queryaudit0_.id=?
and queryaudit0_.lastName_MOD=?
and queryaudit0_.firstName_MOD=?
-- binding parameter [1] as [INTEGER] - [2]
-- binding parameter [2] as [BIGINT] - [1]
-- binding parameter [3] as [BOOLEAN] - [true]
-- binding parameter [4] as [BOOLEAN] - [false]

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@ -0,0 +1,30 @@
select
queryaudit0_.id as id1_3_0_,
queryaudit0_.REV as REV2_3_0_,
defaultrev1_.REV as REV1_4_1_,
queryaudit0_.REVTYPE as REVTYPE3_3_0_,
queryaudit0_.REVEND as REVEND4_3_0_,
queryaudit0_.created_on as created_5_3_0_,
queryaudit0_.createdOn_MOD as createdO6_3_0_,
queryaudit0_.firstName as firstNam7_3_0_,
queryaudit0_.firstName_MOD as firstNam8_3_0_,
queryaudit0_.lastName as lastName9_3_0_,
queryaudit0_.lastName_MOD as lastNam10_3_0_,
queryaudit0_.address_id as address11_3_0_,
queryaudit0_.address_MOD as address12_3_0_,
defaultrev1_.REVTSTMP as REVTSTMP2_4_1_
from
Customer_AUD queryaudit0_ cross
join
REVINFO defaultrev1_
where
queryaudit0_.id=?
and queryaudit0_.lastName_MOD=?
and queryaudit0_.firstName_MOD=?
and queryaudit0_.REV=defaultrev1_.REV
order by
queryaudit0_.REV asc
-- binding parameter [1] as [BIGINT] - [1]
-- binding parameter [2] as [BOOLEAN] - [true]
-- binding parameter [3] as [BOOLEAN] - [false]

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@ -0,0 +1,28 @@
select
queryaudit0_.id as id1_3_0_,
queryaudit0_.REV as REV2_3_0_,
defaultrev1_.REV as REV1_4_1_,
queryaudit0_.REVTYPE as REVTYPE3_3_0_,
queryaudit0_.REVEND as REVEND4_3_0_,
queryaudit0_.created_on as created_5_3_0_,
queryaudit0_.createdOn_MOD as createdO6_3_0_,
queryaudit0_.firstName as firstNam7_3_0_,
queryaudit0_.firstName_MOD as firstNam8_3_0_,
queryaudit0_.lastName as lastName9_3_0_,
queryaudit0_.lastName_MOD as lastNam10_3_0_,
queryaudit0_.address_id as address11_3_0_,
queryaudit0_.address_MOD as address12_3_0_,
defaultrev1_.REVTSTMP as REVTSTMP2_4_1_
from
Customer_AUD queryaudit0_ cross
join
REVINFO defaultrev1_
where
queryaudit0_.id = ?
and queryaudit0_.lastName_MOD = ?
and queryaudit0_.REV=defaultrev1_.REV
order by
queryaudit0_.REV asc
-- binding parameter [1] as [BIGINT] - [1]
-- binding parameter [2] as [BOOLEAN] - [true]

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@ -0,0 +1,258 @@
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
*/
package org.hibernate.userguide.envers;
import java.sql.Timestamp;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.util.Date;
import java.util.List;
import java.util.Map;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import org.hibernate.annotations.CreationTimestamp;
import org.hibernate.envers.AuditReaderFactory;
import org.hibernate.envers.Audited;
import org.hibernate.envers.configuration.EnversSettings;
import org.hibernate.envers.query.AuditEntity;
import org.hibernate.envers.query.AuditQuery;
import org.hibernate.envers.strategy.ValidityAuditStrategy;
import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase;
import org.junit.Test;
import static org.hibernate.testing.transaction.TransactionUtil.doInJPA;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
/**
* @author Vlad Mihalcea
*/
public class QueryAuditWithModifiedFlagTest extends BaseEntityManagerFunctionalTestCase {
@Override
protected Class<?>[] getAnnotatedClasses() {
return new Class<?>[] {
Customer.class,
Address.class
};
}
@Override
protected void addConfigOptions(Map options) {
options.put(
EnversSettings.AUDIT_STRATEGY,
ValidityAuditStrategy.class.getName()
);
}
@Test
public void test() {
doInJPA( this::entityManagerFactory, entityManager -> {
Address address = new Address();
address.setId( 1L );
address.setCountry( "România" );
address.setCity( "Cluj-Napoca" );
address.setStreet( "Bulevardul Eroilor" );
address.setStreetNumber( "1 A" );
entityManager.persist( address );
Customer customer = new Customer();
customer.setId( 1L );
customer.setFirstName( "John" );
customer.setLastName( "Doe" );
customer.setAddress( address );
entityManager.persist( customer );
} );
doInJPA( this::entityManagerFactory, entityManager -> {
Customer customer = entityManager.find( Customer.class, 1L );
customer.setLastName( "Doe Jr." );
} );
doInJPA( this::entityManagerFactory, entityManager -> {
Customer customer = entityManager.getReference( Customer.class, 1L );
entityManager.remove( customer );
} );
List<Number> revisions = doInJPA( this::entityManagerFactory, entityManager -> {
return AuditReaderFactory.get( entityManager ).getRevisions(
Customer.class,
1L
);
} );
doInJPA( this::entityManagerFactory, entityManager -> {
//tag::envers-tracking-properties-changes-queries-hasChanged-example[]
List<Customer> customers = AuditReaderFactory
.get( entityManager )
.createQuery()
.forRevisionsOfEntity( Customer.class, false, true )
.add( AuditEntity.id().eq( 1L ) )
.add( AuditEntity.property( "lastName" ).hasChanged() )
.getResultList();
//end::envers-tracking-properties-changes-queries-hasChanged-example[]
assertEquals( 3, customers.size() );
} );
doInJPA( this::entityManagerFactory, entityManager -> {
//tag::envers-tracking-properties-changes-queries-hasChanged-and-hasNotChanged-example[]
List<Customer> customers = AuditReaderFactory
.get( entityManager )
.createQuery()
.forRevisionsOfEntity( Customer.class, false, true )
.add( AuditEntity.id().eq( 1L ) )
.add( AuditEntity.property( "lastName" ).hasChanged() )
.add( AuditEntity.property( "firstName" ).hasNotChanged() )
.getResultList();
//end::envers-tracking-properties-changes-queries-hasChanged-and-hasNotChanged-example[]
assertEquals( 1, customers.size() );
} );
doInJPA( this::entityManagerFactory, entityManager -> {
//tag::envers-tracking-properties-changes-queries-at-revision-example[]
Customer customer = (Customer) AuditReaderFactory
.get( entityManager )
.createQuery()
.forEntitiesModifiedAtRevision( Customer.class, 2 )
.add( AuditEntity.id().eq( 1L ) )
.add( AuditEntity.property( "lastName" ).hasChanged() )
.add( AuditEntity.property( "firstName" ).hasNotChanged() )
.getSingleResult();
//end::envers-tracking-properties-changes-queries-at-revision-example[]
assertNotNull( customer );
} );
}
//tag::envers-tracking-properties-changes-queries-entity-example[]
@Audited( withModifiedFlag = true )
//end::envers-tracking-properties-changes-queries-entity-example[]
@Entity(name = "Customer")
public static class Customer {
@Id
private Long id;
private String firstName;
private String lastName;
@Temporal( TemporalType.TIMESTAMP )
@Column(name = "created_on")
@CreationTimestamp
private Date createdOn;
@ManyToOne(fetch = FetchType.LAZY)
private Address address;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public Date getCreatedOn() {
return createdOn;
}
public void setCreatedOn(Date createdOn) {
this.createdOn = createdOn;
}
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
}
@Audited
@Entity(name = "Address")
public static class Address {
@Id
private Long id;
private String country;
private String city;
private String street;
private String streetNumber;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getStreet() {
return street;
}
public void setStreet(String street) {
this.street = street;
}
public String getStreetNumber() {
return streetNumber;
}
public void setStreetNumber(String streetNumber) {
this.streetNumber = streetNumber;
}
}
}