IdentifiableJsonSqlitePersistence[T any, K any]

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

Implements: IdentifiableSqlitePersistence[T,K]

Description

Important points

  • The data items must implement the IIdentifiable interface.
  • 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 c._collection and c._model properties.

Configuration parameters

  • collection: (optional) SQLite collection name
  • connection(s):
    • discovery_key: (optional) a 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) a key to retrieve the credentials from ICredentialStore
    • username: (optional) user name
    • password: (optional) user 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) ICredentialStore to resolve credentials

Constructors

InheritIdentifiableJsonSqlitePersistence

Creates a new instance of the persistence component.

InheritIdentifiableJsonSqlitePersistence[T any, K any](overrides ISqlitePersistenceOverrides[T], tableName string) [*IdentifiableJsonSqlitePersistence]()

Methods

ConvertFromPublic

Converts an object value from public to internal format.

(c *IdentifiableJsonSqlitePersistence[T,K]) ConvertFromPublic(value T) (map[string]any, error)

  • value: T - object in public format to convert.
  • returns: map[string]any - converted object in internal format.

ConvertToPublic

Converts an object value from internal to public format.

(c *IdentifiableJsonSqlitePersistence[T,K]) ConvertToPublic(item *sql.Rows) (T, error)

  • rows: *sql.Rows - object in internal format to convert.
  • returns: (T, error) - converted object in public format.

EnsureTable

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

(c *IdentifiableJsonSqlitePersistence[T,K]) EnsureTable(idType string, dataType string)

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

UpdatePartially

Updates only a few selected fields in a data item.

(c *IdentifiableJsonSqlitePersistence[T,K]) UpdatePartially(ctx context.Context, correlationId string, id K, data cdata.AnyValueMap) (result T, err error)

  • ctx: context.Context - operation context.
  • correlationId: string - (optional) transaction id used to trace execution through the call chain.
  • id: K - id of the data item to be updated.
  • data: AnyValueMap - map with fields to be updated.
  • return: (result T, err error) - updated item

Examples

type DummyJsonSqlitePersistence struct {
	*persist.IdentifiableJsonSqlitePersistence[fixtures.Dummy, string]
}

func NewDummyJsonSqlitePersistence() *DummyJsonSqlitePersistence {
	c := &DummyJsonSqlitePersistence{}
	c.IdentifiableJsonSqlitePersistence = persist.InheritIdentifiableJsonSqlitePersistence[fixtures.Dummy, string](c, "dummies_json")
	return c
}

func (c *DummyJsonSqlitePersistence) DefineSchema() {
	c.ClearSchema()
	c.IdentifiableJsonSqlitePersistence.DefineSchema()
	c.EnsureTable("", "")
	c.EnsureIndex(c.TableName+"_key", map[string]string{"(data->'key')": "1"}, map[string]string{"unique": "true"})
}

func (c *DummyJsonSqlitePersistence) GetPageByFilter(ctx context.Context, correlationId string,
	filter cdata.FilterParams, paging cdata.PagingParams) (page cdata.DataPage[fixtures.Dummy], err error) {

	key, ok := filter.GetAsNullableString("Key")
	filterObj := ""
	if ok && key != "" {
		filterObj += "JSON_EXTRACT(data, '$.key')='" + key + "'"
	}

	return c.IdentifiableJsonSqlitePersistence.GetPageByFilter(ctx, correlationId,
		filterObj, paging,
		"", "",
	)
}

func (c *DummyJsonSqlitePersistence) GetCountByFilter(ctx context.Context, correlationId string,
	filter cdata.FilterParams) (count int64, err error) {

	filterObj := ""
	if key, ok := filter.GetAsNullableString("Key"); ok && key != "" {
		filterObj += "JSON_EXTRACT(data, '$.key')='" + key + "'"
	}

	return c.IdentifiableJsonSqlitePersistence.GetCountByFilter(ctx, correlationId, filterObj)
}

func (c *DummyJsonSqlitePersistence) GetOneRandom(ctx context.Context, correlationId string) (item fixtures.Dummy, err error) {
	return c.IdentifiableJsonSqlitePersistence.GetOneRandom(ctx, correlationId, "")
}