IdentifiableMySqlPersistence<T extends IIdentifiable<K>, K>

Extends: MySqlPersistence

Description

The IdentifiableMySqlPersistence class allows you to create persistence components that store data in MySQL databases and implement a number of CRUD operations over data items with unique ids.

Important points

• The data items must implement the IIdentifiable interface.
• In basic scenarios, child classes shall only override getPageByFilter, getListByFilter or deleteByFilter operations with the specific filter function.
• All other operations can be used out of the box.
• In complex scenarios child classes can implement additional operations by accessing the this._collection and this._model properties.

Configuration parameters

• table: (optional) MySQL table name
• schema: (optional) MySQL schema name

connection(s):

• discovery_key: (optional) key to retrieve the connection from IDiscovery
• host: host name or IP address
• port: port number (default: 27017)
• uri: resource URI or connection string with all parameters in it

credential(s):

• store_key: (optional) key to retrieve the credentials from ICredentialStore
• username: (optional) username
• password: (optional) user’s password

options:

• connect_timeout: (optional) number of milliseconds to wait before timing out when connecting a new client (default: 0)
• idle_timeout: (optional) number of milliseconds a client must sit idle in the pool and not be checked out (default: 10000)
• max_pool_size: (optional) maximum number of clients the pool should contain (default: 10)

References

• *:logger:*:*:1.0 - (optional) ILogger components to pass log messages
• *:discovery:*:*:1.0 - (optional) IDiscovery services
• *:credential-store:*:*:1.0 - (optional) Credential stores to resolve credentials (ICredentialStore)

Constructors

Creates a new instance of the persistence component.

public IdentifiableMySqlPersistence(Class documentClass, String tableName, String schemaName)

• tableName: String - (optional) collection name.
• schemaName: String - (optional) a schema name

Fields

Instance methods

convertFromPublicPartial

Converts the given object from the public partial format.

protected Map<String, Object> convertFromPublicPartial(Object value)

• value: Object - the object to convert from the public partial format.
• returns: Object - the initial object.

create

Creates a data item.

public T create(IContext context, T item)

• context: IContext - (optional) a context to trace execution through a call chain.
• item: T - item to be created.
• returns: T - created item

deleteById

Deletes a data item by it’s unique id.

public T deleteById(IContext context, K id)

• context: IContext - (optional) a context to trace execution through a call chain.
• id: K - id of the item to be deleted
• returns: T - deleted item

deleteByIds

Deletes multiple data items by their unique ids.

public void deleteByIds(IContext context, List ids)

• context: IContext - (optional) a context to trace execution through a call chain.
• ids: List - ids of the data items to be deleted.

getListByIds

Gets a list of data items retrieved by given unique ids.

public List getListByIds(IContext context, List ids)

• context: IContext - (optional) a context to trace execution through a call chain.
• ids: List - ids of the data items to be retrieved
• returns: List - data list

getOneById

Gets a data item by its unique id.

public T getOneById(IContext context, K id)

• context: IContext - (optional) a context to trace execution through a call chain.
• id: K - id of the data item to be retrieved.
• returns: - data item

set

Sets a data item. If the data item exists it updates it, otherwise it creates a new data item.

public T set(IContext context, T item)

• context: IContext - (optional) a context to trace execution through a call chain.
• item: T - item to be set.
• returns: T - new or updated item

update

Updates a data item.

public T update(IContext context, T item)

• context: IContext - (optional) a context to trace execution through a call chain.
• item: T - item to be updated.
• returns: T - updated item

updatePartially

Updates only a few selected fields in a data item.

public T updatePartially(IContext context, K id, AnyValueMap data)

• context: IContext - (optional) a context to trace execution through a call chain.
• id: K - id of data item to be updated.
• data: AnyValueMap - map with fields to be updated.
• returns: T - updated item

Examples

{@code
  public class MyMySqlPersistence extends IdentifiableMySqlPersistence<MyData, String> {

     public MyMySqlPersistence() {
         super(MyData.class, "dummies", null);
     }

     @Override
     protected void defineSchema() {
         this.clearSchema();
         this.ensureSchema("CREATE TABLE `" + this._tableName + "` (id VARCHAR(32) PRIMARY KEY, `key` VARCHAR(50), `content` TEXT)");
         this.ensureIndex(this._tableName + "_key", Map.of("key", 1), Map.of("unique", true));
     }

     private String composeFilter(FilterParams filter) {
         filter = filter != null ? filter : new FilterParams();
         String filterCondition = null;

         var key = filter.getAsNullableString("key");

         if (key != null)
             filterCondition = "`key`='" + key + "'";

         return filterCondition;

     }

     public DataPage<MyData> getPageByFilter(IContext context, FilterParams filter, PagingParams paging) {
         return super.getPageByFilter(context, composeFilter(filter), paging, null, null);
     }
 }
 }