Initial Commit ...

2024-01-25 04:41:17 +03:30
commit ff4d0d5dcb
51 changed files with 5949 additions and 0 deletions
@@ -0,0 +1,73 @@
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using MongoDB.Driver;
+
+namespace xDataService.Mongo {
+    public class XAsyncEnumerableAdapter<T> : IAsyncEnumerable<T> {
+        //
+        private readonly IAsyncCursorSource<T> asyncCursorSource;
+
+        //
+        public XAsyncEnumerableAdapter (IAsyncCursorSource<T> asyncCursorSource) {
+            this.asyncCursorSource = asyncCursorSource;
+        }
+
+        //
+        public IAsyncEnumerator<T> GetAsyncEnumerator (CancellationToken cancellationToken) =>
+        new XAsyncEnumeratorAdapter<T> (asyncCursorSource, cancellationToken);
+    }
+
+    public class XAsyncEnumeratorAdapter<T> : IAsyncEnumerator<T> {
+        private readonly IAsyncCursorSource<T> asyncCursorSource;
+        private readonly CancellationToken cancellationToken;
+        private IAsyncCursor<T> asyncCursor;
+        private IEnumerator<T> batchEnumerator;
+
+        public T Current => batchEnumerator.Current;
+
+        public XAsyncEnumeratorAdapter (
+            IAsyncCursorSource<T> asyncCursorSource,
+            CancellationToken cancellationToken
+        ) {
+            //
+            this.asyncCursorSource = asyncCursorSource;
+            this.cancellationToken = cancellationToken;
+        }
+
+        public async ValueTask<bool> MoveNextAsync () {
+            //
+            if (asyncCursor == null) {
+                asyncCursor = await asyncCursorSource
+                    .ToCursorAsync (cancellationToken);
+            }
+
+            //
+            if (batchEnumerator != null &&
+                batchEnumerator.MoveNext ()) {
+                return true;
+            }
+
+            //
+            if (asyncCursor != null &&
+                await asyncCursor.MoveNextAsync (cancellationToken)) {
+                //
+                batchEnumerator?.Dispose ();
+                batchEnumerator = asyncCursor.Current.GetEnumerator ();
+
+                //
+                return batchEnumerator.MoveNext ();
+            }
+
+            //
+            return false;
+        }
+
+        public async ValueTask DisposeAsync () {
+            //
+            await Task.CompletedTask;
+            asyncCursor?.Dispose ();
+            asyncCursor = null;
+        }
+    }
+}