add configurable jellyfin page size

CHANGELOG.md

@@ -39,6 +39,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
     - e.g. if this is set to `1000`, queries taking longer than 1 second will be logged
   - `ETV_SLOW_API_MS` - milliseconds threshold for logging slow API calls (at DEBUG level)
     - This is currently limited to *Jellyfin*
+  - `ETV_JF_PAGE_SIZE` - page size for library scan API calls to Jellyfin; default value is 10
 
 ### Fixed
 - Fix startup on systems unsupported by NvEncSharp

ErsatzTV.Core/SystemEnvironment.cs

@@ -38,16 +38,24 @@ public class SystemEnvironment
         MaximumUploadMb = maximumUploadMb;
 
         string slowDbMsVariable = Environment.GetEnvironmentVariable("ETV_SLOW_DB_MS");
-        if (int.TryParse(slowDbMsVariable, out int slowDbMs))
+        if (int.TryParse(slowDbMsVariable, out int slowDbMs) && slowDbMs > 0)
         {
             SlowDbMs = slowDbMs;
         }
 
         string slowApiMsVariable = Environment.GetEnvironmentVariable("ETV_SLOW_API_MS");
-        if (int.TryParse(slowApiMsVariable, out int slowApiMs))
+        if (int.TryParse(slowApiMsVariable, out int slowApiMs) && slowApiMs > 0)
         {
             SlowApiMs = slowApiMs;
         }
+
+        string jellyfinPageSizeVariable = Environment.GetEnvironmentVariable("ETV_JF_PAGE_SIZE");
+        if (!int.TryParse(jellyfinPageSizeVariable, out int jellyfinPageSize))
+        {
+            jellyfinPageSize = 10;
+        }
+
+        JellyfinPageSize = jellyfinPageSize;
     }
 
     public static string BaseUrl { get; }
@@ -59,4 +67,5 @@ public class SystemEnvironment
     public static int MaximumUploadMb { get; }
     public static int? SlowDbMs { get; }
     public static int? SlowApiMs { get; }
+    public static int JellyfinPageSize { get; set; }
 }

ErsatzTV.Infrastructure/Jellyfin/JellyfinApiClient.cs

@@ -294,17 +294,19 @@ public class JellyfinApiClient : IJellyfinApiClient
     {
         IJellyfinApi service = ServiceForAddress(address);
 
-        const int PAGE_SIZE = 10;
-
         int pages = int.MaxValue;
         for (var i = 0; i < pages; i++)
         {
-            int skip = i * PAGE_SIZE;
+            int skip = i * SystemEnvironment.JellyfinPageSize;
 
-            JellyfinLibraryItemsResponse result = await getItems(service, parentId, skip, PAGE_SIZE);
+            JellyfinLibraryItemsResponse result = await getItems(
+                service,
+                parentId,
+                skip,
+                SystemEnvironment.JellyfinPageSize);
 
             // update page count
-            pages = Math.Min(pages, (result.TotalRecordCount - 1) / PAGE_SIZE + 1);
+            pages = Math.Min(pages, (result.TotalRecordCount - 1) / SystemEnvironment.JellyfinPageSize + 1);
 
             foreach (TItem item in result.Items.Map(item => mapper(maybeLibrary, item)).Somes())
             {