FilePersistence<T> class

Abstract persistence component that stores data in flat files and caches them in memory.

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 _items property and calling save method.

See MemoryPersistence See JsonFilePersister

Configuration parameters

path: path to the file where data is stored

References

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

Example

class MyJsonFilePersistence extends FilePersistence<MyData> {
    MyJsonFilePersistence([String path]): super(JsonPersister(path)) {
    }

     Future<MyData> getByName(String? correlationId, String name) async {
        var item = items.firstWhere((d) => d.name == name);
        return item;
    });

    Future<MyData> set(String correlatonId, MyData item) {
        items = List.from(item.where((d) => d.name != name));
        items.add(item);
        await save(correlationId);
        return item;
    }

}

Inheritance

Object
MemoryPersistence<T>
FilePersistence

Constructors

FilePersistence([JsonFilePersister<T>? persister]): Creates a new instance of the persistence.

Properties

hashCode → int: The hash code for this object.
no setterinherited
items ↔ List<T>: getter/setter pairinherited
loader ↔ ILoader<T>?: getter/setter pairinherited
logger ↔ CompositeLogger: getter/setter pairinherited
maxPageSize ↔ int: getter/setter pairinherited
opened ↔ bool: getter/setter pairinherited
persister ↔ JsonFilePersister<T>: getter/setter pair
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
saver ↔ ISaver<T>?: getter/setter pairinherited

Methods

clear(String? correlationId) → Future: Clears component state.
inherited
close(String? correlationId) → Future: Closes component and frees used resources.
inherited
configure(ConfigParams config) → void: Configures component by passing configuration parameters.
create(String? correlationId, T item) → Future<T?>: Creates a data item.
inherited
deleteByFilterEx(String? correlationId, Function filter) → Future: Deletes data items that match to a given filter.
inherited
getCountByFilterEx(String? correlationId, Function? filter) → Future<int>: Gets a count of data items retrieved by a given filter.
inherited
getListByFilterEx(String? correlationId, Function? filter, Function? sort, dynamic select) → Future<List<T>>: Gets a list of data items retrieved by a given filter and sorted according to sort parameters.
inherited
getOneRandom(String? correlationId, Function? filter) → Future<T?>: Gets a random item from items that match to a given filter.
inherited
getPageByFilterEx(String? correlationId, Function? filter, PagingParams? paging, Function? sort, [dynamic select]) → Future<DataPage<T>>: Gets a page of data items retrieved by a given filter and sorted according to sort parameters.
inherited
isOpen() → bool: Checks if the component is opened.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
open(String? correlationId) → Future: Opens the component.
inherited
save(String? correlationId) → Future: Saves items to external data source using configured saver component.
inherited
setReferences(IReferences references) → void: Sets references to dependent components.
inherited
toString() → String: A string representation of this object.
inherited

Operators

operator ==(Object other) → bool: The equality operator.
inherited