Radicade Public Code

Server/Storage/StudioAssetStorage.cs

@@ -0,0 +1,54 @@
+using System.Numerics;
+using System.Security.Cryptography;
+
+namespace RadicadeServer.Storage;
+
+public sealed record StudioAssetUpload(string Filename, string Hash, long Length);
+
+public static class StudioAssetStorage
+{
+
+
+    public static string Filename(byte[] digest)
+    {
+        var value = new BigInteger(digest, isUnsigned: true, isBigEndian: false);
+        const string alphabet = "0123456789abcdefghijklmnopqrstuvwxyz";
+        var result = "";
+        while (value > 0)
+        {
+            value = BigInteger.DivRem(value, 36, out var remainder);
+            result = alphabet[(int)remainder] + result;
+        }
+        return result.PadLeft(50, '0')[..40];
+    }
+
+    public static async Task<StudioAssetUpload> Save(IFormFile file, CancellationToken cancellation)
+    {
+        await using var input = file.OpenReadStream();
+        return await Save(input, cancellation);
+    }
+
+    public static async Task<StudioAssetUpload> Save(Stream input, CancellationToken cancellation)
+    {
+        Directory.CreateDirectory(DBConfig.CDNStorage);
+        var temporary = Path.Combine(DBConfig.CDNStorage, Guid.NewGuid() + ".uploading");
+        try
+        {
+            await using (var output = System.IO.File.Create(temporary))
+                await input.CopyToAsync(output, cancellation);
+            var length = new FileInfo(temporary).Length;
+            byte[] hash;
+            await using (var storedFile = System.IO.File.OpenRead(temporary))
+                hash = await SHA256.HashDataAsync(storedFile, cancellation);
+            var filename = Filename(hash);
+            var destination = Path.Combine(DBConfig.CDNStorage, filename);
+            try { System.IO.File.Move(temporary, destination); }
+            catch (IOException) when (System.IO.File.Exists(destination)) { }
+            return new StudioAssetUpload(filename, Convert.ToBase64String(hash), length);
+        }
+        finally
+        {
+            if (System.IO.File.Exists(temporary)) System.IO.File.Delete(temporary);
+        }
+    }
+}