JsonFilePersister<T>

Implements: IConfigurable, ILoader, ISaver

Description

The JsonFilePersister class allows you to create persistence components that load and save data from/to a flat file

Configuration parameters

• path: path to the file where the data is stored

Constructors

Creates a new instance of the JSON file persistence component.

public constructor(path?: string)

• path: string - (optional) path to the file where the data is stored.

Properties

path

Gets the file path where the data is stored.

public path(): string

• returns: string - file path where the data is stored.

Sets the file path where data is stored.

public path(value: string)

• value: string - file path where data is stored.

Instance methods

configure

Configures the component by passing its configuration parameters.

public configure(config: ConfigParams): void

• config: ConfigParams - configuration parameters to be set.

load

Loads data items from an external JSON file.

public load(context: IContext): Promise<T[]>

• context: IContext - (optional) a context to trace execution through a call chain.
• returns: Promise<T[]> - loaded items

save

Saves given data items to an external JSON file.

public save(context: IContext, items: T[]): Promise<void>

• context: IContext - (optional) a context to trace execution through a call chain.
• items: T[] - list if data items to save

Examples

let persister = new JsonFilePersister("./data/data.json");
   
await persister.save("123", ["A", "B", "C"]);
...
let items = await persister.load("123");
console.log(items);                      // Result: ["A", "B", "C"]