IdentifiableJsonSqlServerPersistence[T any, K any]

Implements: IdentifiableSqlServerPersistence[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

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

InheritIdentifiableJsonSqlServerPersistence

Creates a new instance of the persistence component.

InheritIdentifiableJsonSqlServerPersistence[T any, K any](overrides ISqlServerPersistenceOverrides[T], tableName string) [*IdentifiableJsonSqlServerPersistence]()

• overrides: ISqlServerPersistenceOverrides[T] - references to child class that overrides virtual methods
• tableName: string - (optional) a table name.

Methods

ConvertFromPublic

Converts an object value from public to internal format.

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

• ctx: context.Context - operation context.
• 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: (result T, err error) - updated item

Examples

type MySqlServerPersistence struct {
	*persist.IdentifiableJsonSqlServerPersistence[MyData, string]
}

func NewMySqlServerPersistence() *MySqlServerPersistence {
	c := &MySqlServerPersistence{}
	c.IdentifiableJsonSqlServerPersistence = persist.InheritIdentifiableJsonSqlServerPersistence[MyData, string](c, "mydata")
	return c
}

func (c *MySqlServerPersistence) DefineSchema() {
	c.ClearSchema()
	c.EnsureTable("", "")
	c.EnsureSchema("ALTER TABLE [" + c.TableName + "] ADD [data_key] AS JSON_VALUE([data],'$.key')")
	c.EnsureIndex(c.TableName+"_key", map[string]string{"data_key": "1"}, map[string]string{"unique": "true"})
}

func (c *MySqlServerPersistence) GetPageByFilter(ctx context.Context, context IContext,
	filter cdata.FilterParams, paging cdata.PagingParams) (page cdata.DataPage[MyData], err error) {

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

	return c.IdentifiableJsonSqlServerPersistence.GetPageByFilter(ctx, context,
		filterObj, paging,
		"", "",
	)
}

func main() {
	persistence := NewMySqlServerPersistence()
	persistence.Configure(context.Background(), cconf.NewConfigParamsFromTuples(
		"host", "localhost",
		"port", 1433,
	))
	err := persitence.Open(context.Background(), "123")

	item, err := persistence.Create(context.Background(), "123", Mydata{Id: "1", Name: "ABC"})
	page, err := persistence.GetPageByFilter("123", *NewFilterParamsFromTuples("name", "ABC"), nil)

	fmt.Println(page.data) // Result: { id: "1", name: "ABC" }

	res, err := persistence.DeleteById(context.Background(),"123", "1")
}