ISettingsStorageHelper.cs

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

namespace CommunityToolkit.Common.Helpers;

/// <summary>
/// Service interface used to store data using key value pairs.
/// </summary>
/// <typeparam name="TKey">The type of keys to use for accessing values.</typeparam>
public interface ISettingsStorageHelper<in TKey>
    where TKey : notnull
{
    /// <summary>
    /// Retrieves a single item by its key.
    /// </summary>
    /// <typeparam name="TValue">Type of object retrieved.</typeparam>
    /// <param name="key">Key of the object.</param>
    /// <param name="value">The <see typeparamref="TValue"/> object for <see typeparamref="TKey"/> key.</param>
    /// <returns>A boolean indicator of success.</returns>
    bool TryRead<TValue>(TKey key, out TValue? value);

    /// <summary>
    /// Saves a single item by its key.
    /// </summary>
    /// <typeparam name="TValue">Type of object saved.</typeparam>
    /// <param name="key">Key of the value saved.</param>
    /// <param name="value">Object to save.</param>
    void Save<TValue>(TKey key, TValue value);

    /// <summary>
    /// Deletes a single item by its key.
    /// </summary>
    /// <param name="key">Key of the object.</param>
    /// <returns>A boolean indicator of success.</returns>
    bool TryDelete(TKey key);

    /// <summary>
    /// Clear all keys and values from the settings store.
    /// </summary>
    void Clear();
}