ASP.NET Core MVC中的HttpContext.Timestamp在哪里？

Question

I would like to get the initial timestamp of the current HTTP request in an ASP.NET Core MVC controller. This timestamp used to be accessible (pre ASP.NET Core) by HttpContext.Timestamp , but Timestamp doesn't seem to be a property of HttpContext anymore.

Where is this property moved to? Or - when it is no longer available - how can I get the timestamp of the HTTP request?

Answer 1

You can add your own middleware to the pipeline which adds additional data to the request. For example:

public void Configure(IApplicationBuilder app)
{
    //Make sure this code is placed at the very start to ensure it 
    //executes as soon as possible
    app.Use(async (context, next) =>
    {
        context.Items.Add("RequestStartedOn", DateTime.UtcNow);
        await next();
    };

    //The rest of your code here...
}

Then later on in the pipeline:

var requestStartedOn = (DateTime)httpContext.Items["RequestStartedOn"];

As an aside, if you intend to reuse this code elsewhere, I would put it in it's own library. For example:

public class RequestTimestampMiddleware
{
    private readonly RequestDelegate _next;

    public RequestTimestampMiddleware(RequestDelegate next)
    {
        _next = next;
    }

    public Task Invoke(HttpContext context)
    {
        context.Items.Add("RequestStartedOn", DateTime.UtcNow);

        // Call the next delegate/middleware in the pipeline
        return this._next(context);
    }
}

And then add an extension method to make it easy to use:

public static class RequestTimestampMiddlewareExtensions
{
    public static IApplicationBuilder UseRequestTimestamp(this IApplicationBuilder builder)
    {
        return builder.UseMiddleware<RequestTimestampMiddleware>();
    }
}

Now your Configure method will look a lot nicer:

public void Configure(IApplicationBuilder app)
{
    app.UseRequestTimestamp();

    //The rest of your code here...
}