[Onebot] Improves file stream handling

Lagrange.OneBot/Core/Operation/Ability/UploadImageOperation.cs

@@ -12,13 +12,17 @@ public class UploadImageOperation : IOperation
 {
     public async Task<OneBotResult> HandleOperation(BotContext context, JsonNode? payload)
     {
-        if (payload?["file"]?.ToString() is { } file && CommonResolver.ResolveStream(file) is { } stream)
+        if (payload?["file"]?.ToString() is { } file)
         {
-            var entity = new ImageEntity(stream);
-            var url = await context.UploadImage(entity);
-            return new OneBotResult(url, 0, "ok");
+            using var stream = await CommonResolver.ResolveStreamAsync(file);
+            if (stream != null)
+            {
+                var entity = new ImageEntity(stream);
+                var url = await context.UploadImage(entity);
+                return new OneBotResult(url, 0, "ok");
+            }
         }
 
-        throw new Exception();
+        throw new Exception("Failed to resolve image file");
     }
 }

Lagrange.OneBot/Core/Operation/Generic/OcrImageOperation.cs

@@ -16,12 +16,16 @@ public class OcrImageOperation() : IOperation
 {
     public async Task<OneBotResult> HandleOperation(BotContext context, JsonNode? payload)
     {
-        if (payload.Deserialize<OneBotOcrImage>(SerializerOptions.DefaultOptions) is { } data && CommonResolver.ResolveStream(data.Image) is { } stream)
+        if (payload.Deserialize<OneBotOcrImage>(SerializerOptions.DefaultOptions) is { } data)
         {
-            var entity = new ImageEntity(stream);
-            var res = await context.OcrImage(entity);
-            return new OneBotResult(res, 0, "ok");
+            using var stream = await CommonResolver.ResolveStreamAsync(data.Image);
+            if (stream != null)
+            {
+                var entity = new ImageEntity(stream);
+                var res = await context.OcrImage(entity);
+                return new OneBotResult(res, 0, "ok");
+            }
         }
-        throw new Exception();
+        throw new Exception("Failed to resolve image for OCR");
     }
 }

Lagrange.OneBot/Core/Operation/Generic/SetGroupPortraitOperation.cs

@@ -14,14 +14,15 @@ public async Task<OneBotResult> HandleOperation(BotContext context, JsonNode? pa
     {
         if (payload?["file"]?.ToString() is { } portrait)
         {
-            var image = CommonResolver.ResolveStream(portrait);
-            if (image == null) throw new Exception();
-
-            var imageEntity = new ImageEntity(image);
-            bool result = await context.SetAvatar(imageEntity);
-            return new OneBotResult(null, result ? 0 : 1, "");
+            using var image = await CommonResolver.ResolveStreamAsync(portrait);
+            if (image != null)
+            {
+                var imageEntity = new ImageEntity(image);
+                bool result = await context.SetAvatar(imageEntity);
+                return new OneBotResult(null, result ? 0 : 1, result ? "ok" : "failed");
+            }
         }
 
-        throw new Exception();
+        throw new Exception("Failed to resolve avatar image");
     }
 }

Lagrange.OneBot/Message/Entity/CommonResolver.cs

@@ -4,30 +4,76 @@ public static class CommonResolver
 {
     private static readonly HttpClient Client = new();
 
+    public static async Task<byte[]?> ResolveAsync(string url, CancellationToken cancellationToken = default)
+    {
+        try
+        {
+            if (url.StartsWith("base64://"))
+                return Convert.FromBase64String(url.Substring("base64://".Length));
+
+            Uri uri = new(url);
+
+            return uri.Scheme switch
+            {
+                "http" or "https" => await (await Client.GetAsync(uri, cancellationToken)).Content.ReadAsByteArrayAsync(cancellationToken),
+                "file" => await File.ReadAllBytesAsync(Path.GetFullPath(uri.LocalPath), cancellationToken),
+                _ => null,
+            };
+        }
+        catch (Exception ex) when (ex is HttpRequestException or FileNotFoundException or DirectoryNotFoundException)
+        {
+            return null;
+        }
+    }
+
+    public static async Task<Stream?> ResolveStreamAsync(string url, CancellationToken cancellationToken = default)
+    {
+        try
+        {
+            if (url.StartsWith("base64://"))
+                return new MemoryStream(Convert.FromBase64String(url.Substring("base64://".Length)));
+
+            Uri uri = new(url);
+
+            return uri.Scheme switch
+            {
+                "http" or "https" => await (await Client.GetAsync(uri, cancellationToken)).Content.ReadAsStreamAsync(cancellationToken),
+                "file" => new FileStream(Path.GetFullPath(uri.LocalPath), FileMode.Open, FileAccess.Read, FileShare.Read),
+                _ => null,
+            };
+        }
+        catch (Exception ex) when (ex is HttpRequestException or FileNotFoundException or DirectoryNotFoundException)
+        {
+            return null;
+        }
+    }
+
     public static byte[]? Resolve(string url)
     {
-        if (url.StartsWith("base64://")) return Convert.FromBase64String(url.Replace("base64://", ""));
+        if (url.StartsWith("base64://"))
+            return Convert.FromBase64String(url.Substring("base64://".Length));
 
         Uri uri = new(url);
 
         return uri.Scheme switch
         {
-            "http" or "https" => Client.GetAsync(uri).Result.Content.ReadAsByteArrayAsync().Result,
             "file" => File.ReadAllBytes(Path.GetFullPath(uri.LocalPath)),
+            "http" or "https" => ResolveAsync(url).GetAwaiter().GetResult(),
             _ => null,
         };
     }
 
     public static Stream? ResolveStream(string url)
     {
-        if (url.StartsWith("base64://")) return new MemoryStream(Convert.FromBase64String(url.Replace("base64://", "")));
+        if (url.StartsWith("base64://"))
+            return new MemoryStream(Convert.FromBase64String(url.Substring("base64://".Length)));
 
         Uri uri = new(url);
 
         return uri.Scheme switch
         {
-            "http" or "https" => Client.GetAsync(uri).Result.Content.ReadAsStreamAsync().Result,
             "file" => new FileStream(Path.GetFullPath(uri.LocalPath), FileMode.Open, FileAccess.Read, FileShare.Read),
+            "http" or "https" => ResolveStreamAsync(url).GetAwaiter().GetResult(),
             _ => null,
         };
     }