FilePersistence<T> class Null safety

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
Implemented types

Constructors

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

Properties

hashCode int
The hash code for this object.
read-onlyinherited
items List<T>
read / writeinherited
loader ILoader<T>?
read / writeinherited
logger CompositeLogger
read / writeinherited
maxPageSize int
read / writeinherited
opened bool
read / writeinherited
persister JsonFilePersister<T>
read / write
runtimeType Type
A representation of the runtime type of the object.
read-onlyinherited
saver ISaver<T>?
read / writeinherited

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.
override
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 non-existent 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