.NET 7 文件上传至控制器时Ubuntu服务器出现CORS错误（已解决）

我找到问题并最终修复了它！原因是我没有在Ubuntu中为www-data用户设置权限。只需运行命令sudo chown -R www-data /var/www/abc.vn/wwwroot/uploads，配合我上面编写的上传API，问题就解决了！

本地环境（Windows + IIS）运行正常，但部署到Ubuntu 22 + Nginx服务器后，上传FormData到控制器时触发CORS错误：

从源地址'http://central.abc.vn'访问'http://api.abc.vn/OnPostUpload'时被CORS策略阻止：请求的资源上不存在'Access-Control-Allow-Origin'标头。如果您需要不透明响应，请将请求的mode设置为'no-cors'以禁用CORS获取资源。

前端请求代码 #

let formData = new FormData();
formData.append('FileDetails', e.target.files[0]);
formData.append('FileName', e.target.files[0].name);
formData.append('TenantId', localStorage.getItem('TenantId'));
fetch(API_URL + 'OnPostUpload',
{
    method: 'POST',
    headers: {
        'Accept': 'application/json',
        'TenantId': localStorage.getItem('TenantId'),
        'Token': localStorage.getItem("Token")
    },
    body: formData
})

后端上传API代码 #

[HttpPost]
[Route("/OnPostUpload")]
public async Task<IActionResult> OnPostUploadAsync([FromForm] FileUploadModel data)
{
    if (data == null)
    {
        return new JsonResult(false);
    }

    if (data != null)
    {
        string path = Path.GetFullPath(Path.Combine(Environment.CurrentDirectory, @"wwwroot/uploads/" + data.TenantId + "/"));
        if (!Directory.Exists(path))
        {
            Directory.CreateDirectory(path);
        }

        var fileName = Guid.NewGuid().ToString("N") + Path.GetExtension(data.FileName);
        var absolutePath = Path.Combine(path, fileName);

        var appfile = await _repository.AddAsync(new AppFile()
        {
            FileName = data.FileName,
            Path = absolutePath,
            TenantId = data.TenantId,
        });
        await _repository.SaveChangesAsync();

        using (var fileStream = new FileStream(absolutePath, FileMode.Create))
        {
            await data.FileDetails.CopyToAsync(fileStream);
        }
        return new JsonResult(new { Path = "uploads/" + data.TenantId + "/" + fileName, AppFileId = appfile.Id });
    }
    return new JsonResult(false);
}

FileUploadModel 定义 #

public class FileUploadModel
{
    public IFormFile FileDetails { get; set; }
    public string FileName { get; set; }
    public string TenantId { get; set; }
}

已尝试的解决方案 #

• 调整文件上传大小限制为100M，无效
• 在Program.cs中配置CORS，仅本地生效，服务器上无效：

  builder.Services.AddCors(options =>
  {
  options.AddPolicy(DefaultCorsPolicyName, builder =>
  {
  builder.WithOrigins("https://localhost:44460",
  "http://central.abc.vn",
  "http://demo.abc.vn")
  .AllowAnyHeader()
  .AllowAnyMethod()
  .AllowCredentials();
  });
  });
  

• 在API方法上添加[EnableCors]特性，无效

内容的提问来源于stack exchange，提问作者Ryan can fly