IdentifiableMySqlPersistence[T, K]

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

Implements: MySqlPersistence[T]

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

InheritIdentifiableMySqlPersistence

Creates a new instance of the persistence component.

InheritIdentifiableMySqlPersistence[T any, K any](overrides IMySqlPersistenceOverrides[T], tableName string) *IdentifiableMySqlPersistence[T, K]

Instance methods

Create

Creates a data item.

(c *IdentifiableMySqlPersistence[T, K]) Create(ctx context.Context, context IContext, item T) (result T, err error)

  • ctx: context.Context - operation context.
  • context: IContext - (optional) a context to trace execution through a call chain.
  • item: T - item to be created.
  • returns: (result T, err error) - created item

DeleteById

Deletes a data item by it’s unique id.

(c *IdentifiableMySqlPersistence[T, K]) DeleteById(ctx context.Context, context IContext, id K) (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 item to be deleted
  • returns: (result T, err error) - deleted item

DeleteByIds

Deletes multiple data items by their unique ids.

(c *IdentifiableMySqlPersistence[T, K]) DeleteByIds(ctx context.Context, context IContext, ids []K) error

  • ctx: context.Context - operation context.
  • context: IContext - (optional) a context to trace execution through a call chain.
  • ids: K[] - ids of the data items to be deleted.
  • returns: error - deleted item.

GetListByIds

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

(c *IdentifiableMySqlPersistence[T, K]) GetListByIds(ctx context.Context, context IContext, ids []K) (items []T, err error)

  • ctx: context.Context - operation context.
  • context: IContext - (optional) a context to trace execution through a call chain.
  • ids: K[] - ids of the data items to be retrieved
  • returns: (items []T, err error) - data list

GetOneById

Gets a data item by its unique id.

(c *IdentifiableMySqlPersistence[T, K]) GetOneById(ctx context.Context, context IContext, id K) (item 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 retrieved.
  • returns: (item T, err error) - data item

Set

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

(c *IdentifiableMySqlPersistence[T, K]) Set(ctx context.Context, context IContext, item T) (result T, err error)

  • ctx: context.Context - operation context.
  • context: string - (optional) a context to trace execution through a call chain.
  • item: T - item to be set.
  • returns: (result T, err error) - new or updated item

Update

Updates a data item.

(c *IdentifiableMySqlPersistence[T, K]) Update(ctx context.Context, context IContext, item T) (result T, err error)

  • ctx: context.Context - operation context.
  • context: IContext - (optional) a context to trace execution through a call chain.
  • item: T - item to be updated.
  • returns: (result T, err error) - updated item

UpdatePartially

Updates only a few selected fields in a data item.

(c *IdentifiableMySqlPersistence[T, K]) UpdatePartially(ctx context.Context, context IContext, id K, data 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 data item to be updated.
  • data: AnyValueMap - map with fields to be updated.
  • returns: (result T, err error) - updated item

Examples

type MyMySqlPersistence struct {
	*persist.IdentifiableMySqlPersistence[MyData, string]
}

func NewMyMySqlPersistence() *MyMySqlPersistence {
	c := &MyMySqlPersistence{}
	c.IdentifiableMySqlPersistence = persist.InheritIdentifiableMySqlPersistence[MyData, string](c, "mydata")
	return c
}

func (c *MyMySqlPersistence) DefineSchema() {
	c.ClearSchema()
	c.IdentifiableMySqlPersistence.DefineSchema()
	// Row name must be in double quotes for properly case!!!
	c.EnsureSchema("CREATE TABLE `" + c.TableName + "` (id VARCHAR(32) PRIMARY KEY, `key` VARCHAR(50), `content` TEXT)")
	c.EnsureIndex(c.IdentifiableMySqlPersistence.TableName+"_key", map[string]string{"key": "1"}, map[string]string{"unique": "true"})
}

func (c *MyMySqlPersistence) 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 += "`key`='" + key + "'"
	}
	sorting := ""

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

func main() {
	persistence := NewMyMySqlPersistence()

	persistence.Configure(context.Background(), NewConfigParamsFromTuples(
		"host", "localhost",
		"port", 27017,
	))

	err := persistence.Open(context.Background(), "123")

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

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