IdentifiableMySqlPersistence

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

Implements: MySqlPersistence, IIdentifiable

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 get_page_by_filter, get_list_by_filter or delete_by_filter 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 self._collection and self._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.

IdentifiableMySqlPersistence(table_name: str = None, schema_name: str = None)

  • table_name: str - (optional) collection name.
  • schema_name: str - (optional) a schema name

Fields

_auto_generate_id

Flag to turn on automated string ID generation

_auto_generate_id: bool = True

Instance methods

_convert_from_public_partial

Converts the given object from the public partial format.

_convert_from_public_partial(value: Any): Any

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

create

Creates a data item.

create(correlation_id: Optional[str], item: T): Optional[T]

  • correlation_id: Optional[str] - (optional) transaction id used to trace execution through the call chain.
  • item: T - item to be created.
  • returns: Optional[T] - created item

delete_by_id

Deletes a data item by it’s unique id.

delete_by_id(correlation_id: Optional[str], id: Any): T

  • correlation_id: Optional[str] - (optional) transaction id used to trace execution through the call chain.
  • id: Any - id of the item to be deleted
  • returns: T - deleted item

delete_by_ids

Deletes multiple data items by their unique ids.

delete_by_ids(correlation_id: Optional[str], ids: List[Any])

  • correlation_id: Optional[str] - (optional) transaction id used to trace execution through the call chain.
  • ids: List[Any] - ids of the data items to be deleted.

get_list_by_ids

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

get_list_by_ids(correlation_id: Optional[str], ids: List[Any]): List[T]

  • correlation_id: Optional[str] - (optional) transaction id used to trace execution through the call chain.
  • ids: List[Any] - ids of the data items to be retrieved
  • returns: List[T] - data list

get_one_by_id

Gets a data item by its unique id.

get_one_by_id(correlation_id: Optional[str], id: Any): T

  • correlation_id: Optional[str] - (optional) transaction id used to trace execution through the call chain.
  • id: Any - id of the data item to be retrieved.
  • returns: T - data item

set

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

set(correlation_id: Optional[str], item: T): Optional[T]

  • correlation_id: Optional[str] - (optional) transaction id used to trace execution through the call chain.
  • item: T - item to be set.
  • returns: Optional[T] - new or updated item

update

Updates a data item.

update(correlation_id: Optional[str], item: T): Optional[T]

  • correlation_id: Optional[str] - (optional) transaction id used to trace execution through the call chain.
  • item: T - item to be updated.
  • returns: Optional[T] - updated item

update_partially

Updates only a few selected fields in a data item.

update_partially(correlation_id: Optional[str], id: Any, data: AnyValueMap): Optional[T]

  • correlation_id: Optional[str] - (optional) transaction id used to trace execution through the call chain.
  • id: Any - id of data item to be updated.
  • data: AnyValueMap - map with fields to be updated.
  • returns: Optional[T] - updated item

Examples

class MyMySqlPersistence(IdentifiableMySqlPersistence):
    def __init__(self):
        super(MyMySqlPersistence, self).__init__("mydata", MyDataMySqlSchema())

    def __compose_filter(self, filter):
        filter = filter or FilterParams()
        criteria = []
        name = filter.get_as_nullable_string('name')
        if name:
            criteria.append({'name': name})
        return {'$and': criteria} if len(criteria) > 0 else None

    def get_page_by_filter(self, correlation_id, filter, paging):
        return super().get_page_by_filter(correlation_id, self.__compose_filter(filter), paging, None, None)

persistence = MyMySqlPersistence()
persistence.configure(ConfigParams.from_tuples(
    "host", "localhost",
    "port", 27017
))

persistence.open('123')
persistence.create('123', {'id': "1", 'name': "ABC"})

page = persistence.get_page_by_filter('123', FilterParams.from_tuples('name', 'ABC'), None)
print(page.data) # Result: { id: "1", name: "ABC" }
persistence.delete_by_id("123", "1")
# ...