FilePersistence<T>

Extends: MemoryPersistence

Implements: IConfigurable

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

Creates a new instance of the file persistence component.

public constructor(persister?: JsonFilePersister)

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

Fields

Instance methods

configure

Configures the component by passing its configuration parameters.

public configure(config: ConfigParams): void

• config: ConfigParams - configuration parameters to be set.

Examples

class MyJsonFilePersistence extends FilePersistence<MyData> {
    public constructor(path?: string) {
        super(new JsonPersister(path));
    }
    
    public async getByName(context: IContext, name: string): Promise<MyData> {
        let item = this._items.find((d) => d.name == name);
        retur item;
    }); 
     
    public async set(context: IContext, item: MyData): Promise<MyData> {
        this._items = this._items.filter((d) => d.name != name);
        this._items.push(item);
        await this.save(context);
        return item;
    }
  
}

See also

• MemoryPersistence

• JsonFilePersister