The goal of this document is to show implications for tosca model template to move from Eclipse-Link to Hibernate. Primary focus is to show the database compatibility and eventually schema changes where is necessary.
In all these tests I am using some strategies to make sure that tables and fields name generated by Hibernate will be the same as Eclipse-Link.
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Definitions
- ElementCollection: Specifies a collection of instances of a basic type or embeddable class. Must be specified if the collection is to be mapped by means of a collection table.
- OneToMany: Specifies a many-valued association with one-to-many multiplicity. If the collection is defined using generics to specify the element type, the associated target entity type need not be specified; otherwise the target entity class must be specified. If the relationship is bidirectional, the
mappedBy
element must be used to specify the relationship field or property of the entity that is the owner of the relationship. TheOneToMany
annotation may be used within an embeddable class contained within an entity class to specify a relationship to a collection of entities. If the relationship is bidirectional, themappedBy
element must be used to specify the relationship field or property of the entity that is the owner of the relationship. When the collection is ajava.util.Map
, thecascade
element and theorphanRemoval
element apply to the map value.
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Control Loop runtime uses persistence.xml
file: is the deployment descriptor file for persistence using JPA. It specifies the persistence units and declares the managed persistence classes, the object/relation mapping, and the database connection details.
Hibernate
SpringBoot auto-configuration can automatically scan entity classes. In Control Loop Runtime we can use @EntityScan annotation because entity classes are not placed in the main application package or its sub-packages. In this situation, we need declare the package or list of packages in the main configuration class within @EntityScan annotation.
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Note about precision in DATETIME (https://mariadb.com/kb/en/datetime/): MariaDB can store microseconds with a precision between 0 and 6. If no microsecond precision is specified, then 0 is used by default.
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@Embeddable @Data public class ExampleKey implements Serializable { private static final long serialVersionUID = 1L; @Column(name = "name", length = 120) private String name; @Column(name = "version", length = 20) private String version; } @Entity @Table(name = "Example") @Data public class JpaExample implements Serializable { private static final long serialVersionUID = 1L; @EmbeddedId @VerifyKey @NotNull private ExampleKey key; @Column private Boolean primed; @Column(name = "timeStamp", precision = 3) @Temporal(TemporalType.TIMESTAMP) @NotNull private Date timeStamp; } |
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ElementCollection should be used with basic type or embeddable class, this example shows side effects using it with entity.
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@Entity @Table(name = "ExampleObjMapEc") @Data public class JpaExampleObjMapEc implements Serializable { private static final long serialVersionUID = 1L; @EmbeddedId @VerifyKey @NotNull private ExampleKey key; @ElementCollection @Lob private Map<@NotNull String, @NotNull JpaExample> examples; } |
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ElementCollection should be used with basic type or embeddable class, this example shows side effects using it with entity.
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@Entity @Table(name = "ExampleObjListEc") @Data public class JpaExampleObjListEc implements Serializable { private static final long serialVersionUID = 1L; @EmbeddedId @VerifyKey @NotNull private ExampleKey key; @ElementCollection @Lob private List<@NotNull JpaExample> examples; } |
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MariaDB [controlloop]> select * from ExampleObjMap;
+---------------+---------+
| name | version |
+---------------+---------+
| ExampleObjMap | 1.0.0 |
+---------------+---------+
MariaDB [controlloop]> select * from Example;
+----------+---------+--------+-----------+
| name | version | primed | timeStamp |
+----------+---------+--------+-----------+
| example1 | 1.0.0 | NULL | NULL |
| example2 | 1.0.0 | NULL | NULL |
+----------+---------+--------+-----------+
MariaDB [controlloop]> select * from ExampleObjMap_Example;
+---------------+----------------+------------+---------------+--------------+
| parent_name | parent_version | child_name | child_version | examples_KEY |
+---------------+----------------+------------+---------------+--------------+
| ExampleObjMap | 1.0.0 | example1 | 1.0.0 | MyKey1 |
| ExampleObjMap | 1.0.0 | example2 | 1.0.0 | MyKey2 |
+---------------+----------------+------------+---------------+--------------+
Performance issue
Using current version, for each operation save/read/delete of the service template below, control-loop runtime application makes 51 access to database14 tables and handles 51 rows.
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name: ToscaServiceTemplateSimple version: 1.0.1 tosca_definitions_version: tosca_simple_yaml_1_3 data_types: onap.datatypes.ToscaConceptIdentifier: derived_from: tosca.datatypes.Root properties: name: type: string required: true version: type: string required: true node_types: org.onap.policy.clamp.controlloop.Participant: version: 1.0.1 derived_from: tosca.nodetypes.Root properties: provider: type: string requred: false org.onap.policy.clamp.controlloop.ControlLoopElement: version: 1.0.1 derived_from: tosca.nodetypes.Root properties: provider: type: string requred: false participantType: type: onap.datatypes.ToscaConceptIdentifier requred: true startPhase: type: integer required: false constraints: - greater_or_equal: 0 metadata: common: true description: check wiki documentation about start phase stopped simultaneously org.onap.policy.clamp.controlloop.ControlLoop: version: 1.0.1 derived_from: tosca.nodetypes.Root properties: provider: type: string requred: false elements: type: list required: true entry_schema: type: onap.datatypes.ToscaConceptIdentifier org.onap.policy.clamp.controlloop.K8SMicroserviceControlLoopElement: version: 1.0.1 derived_from: org.onap.policy.clamp.controlloop.ControlLoopElement properties: chart: type: string required: true configs: type: list required: false requirements: type: string requred: false templates: type: list required: false entry_schema: values: type: string requred: true topology_template: node_templates: org.onap.k8s.controlloop.K8SControlLoopParticipant: version: 2.3.4 type: org.onap.policy.clamp.controlloop.Participant type_version: 1.0.1 description: Participant for K8S properties: provider: ONAP org.onap.domain.database.HelloWorld_K8SMicroserviceControlLoopElement: # Chart from any chart repository configured on helm client. version: 1.2.3 type: org.onap.policy.clamp.controlloop.K8SMicroserviceControlLoopElement type_version: 1.0.0 description: Control loop element for the K8S microservice for Hello World properties: provider: ONAP participantType: name: org.onap.k8s.controlloop.K8SControlLoopParticipant1 version: 2.3.4 chart: chartId: name: dummy version: 0.1.0 releaseName: test namespace: test org.onap.domain.database.PMSH_K8SMicroserviceControlLoopElement: # Chart from local file system version: 1.2.3 type: org.onap.policy.clamp.controlloop.K8SMicroserviceControlLoopElement type_version: 1.0.0 description: Control loop element for the K8S microservice for PMSH properties: provider: ONAP participantType: name: org.onap.k8s.controlloop.K8SControlLoopParticipant2 version: 2.3.4 startPhase: 1 chart: chartId: name: dcae-pmsh version: 8.0.0 namespace: onap releaseName: pmshms repository: repoName: chartmuseum protocol: http address: 10.152.183.120 port: 80 userName: onapinitializer password: demo123456! overrideParams: global.masterPassword: test org.onap.domain.database.Local_K8SMicroserviceControlLoopElement: # Chart installation without passing repository name version: 1.2.3 type: org.onap.policy.clamp.controlloop.K8SMicroserviceControlLoopElement type_version: 1.0.0 description: Control loop element for the K8S microservice for local chart properties: provider: ONAP participantType: name: org.onap.k8s.controlloop.K8SControlLoopParticipant version: 2.3.4 chart: chartId: name: nginx-ingress version: 0.9.1 releaseName: nginxms namespace: test repository: repoName: nginx-stable org.onap.domain.sample.GenericK8s_ControlLoopDefinition: version: 1.2.3 type: org.onap.policy.clamp.controlloop.ControlLoop type_version: 1.0.0 description: Control loop for Hello World properties: provider: ONAP elements: - name: org.onap.domain.database.HelloWorld_K8SMicroserviceControlLoopElement version: 1.2.3 - name: org.onap.domain.database.PMSH_K8SMicroserviceControlLoopElement version: 1.2.3 - name: org.onap.domain.database.Local_K8SMicroserviceControlLoopElement version: 1.2.3 |
Multi templates
Right now using Spring repositories it is possible to create more than one service template, as service templates in policy-models/tosca.
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- Move to Hibernate with EclipseLink tables is probably possible.
- The presence of longblob types used to store whole objects is an issues, it is readable only by Java language or by any other language compatible with Java binary code. I am not sure if a db-migrator can handle that.
- Document databases store all information for a given object in a single instance in the database, and every stored object can be different from every other. Each operation save/read/delete of a service template, could be done using one access to a document. So, using Cassandra/MongoDB will solve all issues.
JpaRepository
and CassandraRepository
/MongoRepository
extendCrudRepository
and expose the capabilities of the underlying persistence technology in addition to the rather generic persistence technology-agnostic interfaces like e.g.CrudRepository
.