Additional checking for post uploads

T120B165-ImgBoard/Controllers/PostController.cs

@@ -22,7 +22,8 @@ public class PostController(
     ITagService tagService,
     ICommentService commentService,
     IFileService fileService,
-    IWebHostEnvironment env
+    IWebHostEnvironment env,
+    ILogger<PostController> logger
     ): ControllerBase
 {
     
@@ -117,6 +118,7 @@ public class PostController(
     /// <response code="400">If request is malformed</response>
     /// <response code="401">If authentication is missing</response>
     /// <response code="403">If authorization is missing</response>
+    /// <response code="422">If data provided does not fit constraints</response>
     [HttpPost]
     [Authorize(Roles = UserRoles.Regular)]
     [ProducesResponseType(StatusCodes.Status201Created)]
@@ -129,6 +131,11 @@ public class PostController(
         var userId = HttpContext.User.Claims.First(c => c.Type == ClaimTypes.NameIdentifier).Value;
         var user = await userService.GetUserById(userId);
         if (user == null) return Unauthorized();
+        
+        if (dto.FileSize.Value > 10*1024*1024) return Problem("File cannot exceed 10MB", statusCode: StatusCodes.Status422UnprocessableEntity);
+        
+        if (dto.FileMimeType != "image/png" && dto.FileMimeType != "image/jpeg")
+            return Problem("File must be image", statusCode: StatusCodes.Status422UnprocessableEntity);
 
         var maybeTags = await TagNamesToTags(dto.Tags);
         List<Tag> tags;
@@ -164,6 +171,7 @@ public class PostController(
     /// <response code="401">If authentication is missing</response>
     /// <response code="403">If authorization is missing</response>
     /// <response code="404">If post or file is not found</response>
+    /// <response code="409">If a chunk was already uploaded</response>
     /// <response code="415">If finished upload mime does not match provided</response>
     [HttpPatch("{postId:int}/files/{fileId:int}")]
     [Authorize(Roles = UserRoles.Regular)]
@@ -214,11 +222,18 @@ public class PostController(
 
         // Append the chunk to the temporary file
         var tempFilePath = fileRecord.FilePath;
-        await using (var stream = new FileStream(tempFilePath, FileMode.Append, FileAccess.Write, FileShare.None, bufferSize: 4096, useAsync: true))
+        try
         {
+            await using var stream = new FileStream(tempFilePath, FileMode.Append, FileAccess.Write, FileShare.None,
+                bufferSize: 4096, useAsync: true);
             stream.Seek(start, SeekOrigin.Begin);
             await Request.Body.CopyToAsync(stream);
         }
+        catch (Exception e)
+        {
+            logger.LogCritical(e.ToString());
+            return Problem("Chunk has already been uploaded", statusCode: StatusCodes.Status409Conflict);
+        }
 
         // Check if the upload is complete
         // Return 202 Accepted for a successful intermediate chunk