ngx-webstorage-service
Version:
Angular service wrappers for the webstorage API
62 lines (61 loc) • 3.55 kB
TypeScript
import { StorageService } from './storage.service';
import { StorageTranscoder, StorageDecoder, StorageEncoder } from './storage-transcoder';
/**
* A storage service implementation that is used as a proxy for another storage service. This is used to create storage services with a
* different default transcoder.
*/
export declare class ProxyStorageService<T> implements StorageService<T> {
private readonly defaultTranscoder;
private readonly subject;
/**
* Creates a new `ProxyStorageService` instance that uses the specified transcoder by default for read and write operations. Actual
* read and writes are delegated to given storage service.
*
* @param defaultTranscoder Transcoder which is to be used by default for storage read and write operations.
* @param subject Storage service which should handle to actual storage of data.
*/
constructor(defaultTranscoder: StorageTranscoder<T>, subject: StorageService);
/**
* Checks whether an entry with the specified key exists in the storage.
*
* @param key Identifier of the entry for which its presence in the storage is to be checked.
* @returns `true` if an entry with the specified key exists in the storage, `false` if not.
*/
has(key: string): boolean;
get(key: string, decoder?: StorageDecoder<any>): any;
/**
* Creates or updates the entry identified by the specified key with the given value. The specified encoder is used to convert the given
* value into a format that can be stored by the storage service's underlying storage.
*
* Storing a value into the storage service will ensure that an equivalent of the value can be read back, i.e. the data and structure of
* the value will be the same. It, however, does not necessarily return the same reference.
*
* @param key Identifier of the entry which is to be created or updated.
* @param value Value which is to be stored.
* @param encoder Encoder used to convert the given value into a format that can be used for storage.
*/
set(key: string, value: any, encoder?: StorageEncoder<any>): void;
/**
* Removes the entry that is identified by the specified key. Attempting to remove an entry for an unknown key will have no effect.
* Attempting to retrieve an entry via the `get` method after it has been removed will result in `undefined`.
*
* @param key Identifier of the entry which is to be removed.
*/
remove(key: string): void;
/**
* Clears the storage by removing all entries. Subsequent `get(x)` calls for a key *x* will return `undefined`, until a new value is set
* for key *x*.
*/
clear(): void;
/**
* Creates a new storage service that uses the specified transcoder by default for read and write operations. The new storage service
* uses the storage service on which this function is invoked as underlying storage. Both storage services will thus be able to access
* the same data.
*
* The default transcoder will not be changed for the storage service on which this function is invoked.
*
* @param transcoder Transcoder that should be used by default for read and write operations by the new storage service.
* @returns A new storage service that uses the specified transcoder by default.
*/
withDefaultTranscoder<X>(transcoder: StorageTranscoder<X>): StorageService<X>;
}