IdentifiableJsonMySqlPersistence<T extends IIdentifiable<K>, K>

Abstract persistence component that stores data in MySQL in JSON or JSONB fields and implements a number of CRUD operations over data items with unique ids.

Extends: IdentifiableMySqlPersistence<T, K>

Description

The IdentifiableJsonMySqlPersistence class allows you to create persistence components that store data in JSON or JSONB fields and implement a number of CRUD operations over data items with unique ids.

Important points

  • The JSON table has only two fields: id and data.
  • In basic scenarios child classes shall only override getPageByFilter, getListByFilter or deleteByFilter operations with a specific filter function.
  • All other operations can be used out of the box.
  • In complex scenarios child classes can implement additional operations by accessing 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 can 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) ICredentialStore to resolve credentials

Constructors

Creates a new instance of the persistence component.

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

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

Instance methods

convertFromPublic

Converts object value from public to internal format.

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

  • value: Object - object in public format to convert.
  • returns: Map<String, Object> - converted object in internal format.

convertToPublic

Converts object value from internal to public format.

protected T convertToPublic(Map<String, Object> value)

  • value: Map<String, Object> - object in internal format to convert.
  • returns: T - converted object in public format.

ensureTable

Adds DML statement to automatically create a JSON(B) table

protected void ensureTable(String idType, String dataType)

  • idType: String - type of the id column (default: VARCHAR(32))
  • dataType: String - type of the data column (default: JSON)

updatePartially

Updates only 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 the data item to be updated.
  • data: AnyValueMap - map with fields to be updated.
  • return: Promise<T> - updated item

Examples