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]

overrides: IMySqlPersistenceOverrides[T] - References to override virtual methods.
tableName: string - (optional) table name.

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")
}