Persistence component that loads and saves data from/to a flat file.
It is used by FilePersistence, but can be useful on its own.
Implements: IConfigurable, ILoader
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(correlationId: string): Promise<T[]>
- correlationId: string - (optional) transaction id used to trace execution through the call chain.
- returns: Promise<T[]> - loaded items
save
Saves given data items to an external JSON file.
public
save(correlationId: string, items: T[]): Promise<void>
- correlationId: string - (optional) transaction id used to trace execution through the 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"]