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.

JsonFilePersister([String path])

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

Properties

path

Gets the file path where the data is stored.

String get path

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

Sets the file path where data is stored.

set path(String value)

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

Instance methods

configure

Configures the component by passing its configuration parameters.

@override

void configure(ConfigParams config)

• config: ConfigParams - configuration parameters to be set.

load

Loads data items from an external JSON file.

@override

Future<List<T>> load(String correlation_id)

• correlationId: String? - (optional) transaction id used to trace execution through the call chain.
• returns: Future<List<T>> - loaded items

save

Saves given data items to an external JSON file.

@override

Future save(String correlation_id, List<T?> items)

• correlationId: String? - (optional) transaction id used to trace execution through the call chain.
• items: List<T?> - list if data items to save

Examples

var persister = JsonFilePersister("./data/data.json");
await persister.save("123", ["A", "B", "C"]);

    ...

var items = await persister.load("123");
print(items);  // Result: ["A", "B", "C"]