Scrobbling Stability (#3863)

Co-authored-by: Amelia <77553571+Fesaa@users.noreply.github.com>

API/Services/Plus/KavitaPlusApiService.cs

@@ -0,0 +1,75 @@
+#nullable enable
+using System.Threading.Tasks;
+using API.DTOs.Scrobbling;
+using API.Extensions;
+using Flurl.Http;
+using Kavita.Common;
+using Microsoft.Extensions.Logging;
+
+namespace API.Services.Plus;
+
+/// <summary>
+/// All Http requests to K+ should be contained in this service, the service will not handle any errors.
+/// This is expected from the caller.
+/// </summary>
+public interface IKavitaPlusApiService
+{
+    Task<bool> HasTokenExpired(string license, string token, ScrobbleProvider provider);
+    Task<int> GetRateLimit(string license, string token);
+    Task<ScrobbleResponseDto> PostScrobbleUpdate(ScrobbleDto data, string license);
+}
+
+public class KavitaPlusApiService(ILogger<KavitaPlusApiService> logger): IKavitaPlusApiService
+{
+    private const string ScrobblingPath = "/api/scrobbling/";
+
+    public async Task<bool> HasTokenExpired(string license, string token, ScrobbleProvider provider)
+    {
+        var res = await Get(ScrobblingPath + "valid-key?provider=" + provider + "&key=" + token, license, token);
+        var str = await res.GetStringAsync();
+        return bool.Parse(str);
+    }
+
+    public async Task<int> GetRateLimit(string license, string token)
+    {
+        var res = await Get(ScrobblingPath + "rate-limit?accessToken=" + token, license, token);
+        var str = await res.GetStringAsync();
+        return int.Parse(str);
+    }
+
+    public async Task<ScrobbleResponseDto> PostScrobbleUpdate(ScrobbleDto data, string license)
+    {
+        return await PostAndReceive<ScrobbleResponseDto>(ScrobblingPath + "update", data, license);
+    }
+
+    /// <summary>
+    /// Send a GET request to K+
+    /// </summary>
+    /// <param name="url">only path of the uri, the host is added</param>
+    /// <param name="license"></param>
+    /// <param name="aniListToken"></param>
+    /// <returns></returns>
+    private static async Task<IFlurlResponse> Get(string url, string license, string? aniListToken = null)
+    {
+        return await (Configuration.KavitaPlusApiUrl + url)
+            .WithKavitaPlusHeaders(license, aniListToken)
+            .GetAsync();
+    }
+
+    /// <summary>
+    /// Send a POST request to K+
+    /// </summary>
+    /// <param name="url">only path of the uri, the host is added</param>
+    /// <param name="body"></param>
+    /// <param name="license"></param>
+    /// <param name="aniListToken"></param>
+    /// <typeparam name="T">Return type</typeparam>
+    /// <returns></returns>
+    private static async Task<T> PostAndReceive<T>(string url, object body, string license, string? aniListToken = null)
+    {
+        return await (Configuration.KavitaPlusApiUrl + url)
+            .WithKavitaPlusHeaders(license, aniListToken)
+            .PostJsonAsync(body)
+            .ReceiveJson<T>();
+    }
+}