【发布时间】:2021-10-14 09:48:16
【问题描述】:
我想将一个变量传递到我的中间件的标头中。在我的控制器中,我使用username 来保存在视图中输入的值。然后我在想如果我使用TempData 我可以将username 的值传递给我的中间件类并将其添加到标题中。我注意到在它最终进入 if 语句 ( if (tempData.ContainsKey("username"))) 并添加标题之后。当我进入下一页时,它会返回中间件......它不会进入 if 语句并继续下一行 correlationId = Guid.NewGuid().ToString();`。这是在中间件中传递变量并将其添加到标头中的正确方法吗?
控制器:
[HttpPost]
public IActionResult AddressValidate(IFormCollection form)
{
// if radio button was checked, perform the following var request.
// username
string username = form["UserName"];
TempData["username"] = username;
TempData.Keep();
string status = form["Status"];
_logger.LogInformation("Current user logged in: {@Username}", username);
......
return RedirectToAction("SecondIndex", "Second")
}
Middleware:
public class CorrelationIdMiddleware
{
private readonly ITempDataDictionaryFactory _tempDataDictionaryFactory;
private const string CorrelationIdHeaderKey = "X-Correlation-ID";
private readonly RequestDelegate _next;
private readonly ILogger _logger;
public CorrelationIdMiddleware(RequestDelegate next, ILoggerFactory loggerFactory, ITempDataDictionaryFactory tempDataDictionaryFactory)
{
_next = next ?? throw new ArgumentNullException(nameof(next));
_logger = loggerFactory.CreateLogger<CorrelationIdMiddleware>();
_tempDataDictionaryFactory = tempDataDictionaryFactory;
}
public async Task Invoke(HttpContext httpContext)
{
string correlationId = null;
string userName;
var tempData = _tempDataDictionaryFactory.GetTempData(httpContext);
if (httpContext.Request.Headers.TryGetValue(
CorrelationIdHeaderKey, out StringValues correlationIds))
{
correlationId = correlationIds.FirstOrDefault(k =>
k.Equals(CorrelationIdHeaderKey));
_logger.LogInformation("CorrelationId from Request Header: {@correlationId} ", correlationId);
}
else
{
if (tempData.ContainsKey("username"))
{
userName = tempData["username"].ToString();
httpContext.Request.Headers.Add("X-username", userName);
}
correlationId = Guid.NewGuid().ToString();
httpContext.Request.Headers.Add(CorrelationIdHeaderKey,
correlationId);
_logger.LogInformation("Generated CorrelationId: {@correlationId}", correlationId);
}
httpContext.Response.OnStarting(() =>
{
if (!httpContext.Response.Headers.
TryGetValue(CorrelationIdHeaderKey,
out correlationIds))
httpContext.Response.Headers.Add(
CorrelationIdHeaderKey, correlationId);
return Task.CompletedTask;
});
await _next.Invoke(httpContext);
}
}
像这样的会话?
【问题讨论】:
-
“正确”仅取决于您的情况。如果这可行并满足您的需求,那么它可能就足够正确了。
-
@DavidL 我明白了,但这是它应该表现的方式吗?就像它首先将用户名添加到标题中一样,然后重定向到下一页,它不会输入 if 语句来添加标题。这是它应该表现的方式吗?抱歉,我是中间件流程的新手
-
您是否调试过您的 if 语句,检查 headers 集合是否符合您的预期?
-
我在调试
httpContext.Request.Headers时没有看到标题集合,是不是在其他地方?
标签: c# asp.net-mvc asp.net-core-mvc middleware tempdata