FilePersistence

Implements: MemoryPersistence

Description

The FilePersistence class allows you to create persistence components that store data in flat files and chache them in memory.

Important points

• This is the most basic persistence component that is only able to store data items of any type.
• Specific CRUD operations over the data items must be implemented in child classes by accessing the self._items property and calling the save method.

Configuration parameters

• path: path to the file where data is stored

References

• *:logger:*:*:1.0 - (optional) ILogger components to pass log messages

Constructors

NewFilePersistence

Creates a new instance of the file persistence component. T data.ICloneable[T] any type that implemented ICloneable interface of getting element.

NewFilePersistence[T data.ICloneable[T]](persister *JsonFilePersister) *FilePersistence[T]

• persister: *JsonFilePersister - (optional) persister component that loads and saves data from/to a flat file.

Fields

Methods

Configure

Configures the component by passing its configuration parameters.

(c *FilePersistence[T]) Configure(ctx context.Context, conf *config.ConfigParams)

• ctx: context.Context - operation context.
• config: *config.ConfigParams - configuration parameters to be set.

Examples

type MyJsonFilePersistence struct {
	*FilePersistence[*MyData]
}

func NewMyJsonFilePersistence(path string) *MyJsonFilePersistence {
	return &MyJsonFilePersistence{
		FilePersistence: NewFilePersistence(NewJsonFilePersister[*MyData](path)),
	}
}

func (c *MyJsonFilePersistence) GetByName(ctx context.Context, correlationId string,
	name string) (*MyData, error) {
	for _, v := range c.Items {
		if v.Name == name {
			return v, nil
		}
	}

	var defaultValue *MyData
	return defaultValue, nil
}

func (c *MyData) Clone() *MyData {
	return &MyData{Id: c.Id, Name: c.Name}
}

type MyData struct {
	Id   string
	Name string
}

See also

• MemoryPersistence

• JsonFilePersister