c#错误请求中的cURL调用

Question

我正在尝试在c# .net环境中执行以下cURL调用

curl -XPOST -d 'Metadata/Type = "sas"' http://bms.org/bcknd/republish

C#代码如下：

var requestContent = new FormUrlEncodedContent(new[] { new KeyValuePair<string, string>("Metadata/Type", "\"sas\""), });
HttpResponseMessage response = await client.PostAsync("http://bms.org/bcknd/republish", requestContent);
HttpContent responseContent = response.Content;

using (var reader = new StreamReader(await responseContent.ReadAsStreamAsync()))
{
            Console.WriteLine(await reader.ReadToEndAsync());
}

我收到一个400 Bad request，当我把它打印出来的时候。也许它与curl调用中的-XPOST和-d参数有关？

编辑:这是来自curl的http请求：

POST http://bms.org/bcknd/republish HTTP/1.1
Host: bms.org/bcknd
User-Agent: curl/7.48.0
Accept: */*
Content-Length: 43
Content-Type: application/x-www-form-urlencoded

Metadata/Type = "sas"

下面是我的代码中的http请求：

POST http://bms.org/bcknd/republish HTTP/1.1
Accept: */*
User-Agent: curl/7.48.0
Content-Type: application/x-www-form-urlencoded; charset=utf-8
Host: bms.org/bcknd
Content-Length: 43
Connection: Keep-Alive

Metadata/Type = "sas"

Answer 1

短版

将数据作为不带url编码的StringContent发布，并在尝试读取响应正文之前检查响应状态。请确保调用在应用程序退出之前完成，否则应用程序退出时调用将被取消。这意味着，在Main中使用async Task，而不是async void：

class Program
{
    static async Task Main(string[] args)
    {
        var client=new HttpClient();
        var data = new StringContent("Metadata/Type=\"sas\"",Encoding.UTF8,"application/x-www-form-urlencoded");
        var response = await client.PostAsync("http://www.google.com/bcknd/republish", data);
        if(response.IsSuccessStatusCode)
        {
            var  responseContent = response.Content;
            var body=await response.Content.ReadAsStringAsync();
            Console.WriteLine(body);
        }
        else 
        {
            Console.WriteLine($"Oops! {response.StatusCode} - {response.ReasonPhrase}");
        }
    }
}

说明

在这种情况下，了解实际发送的内容是非常重要的。为此，可以使用像Fiddler或Charles这样的调试代理。

Curl和-d一起发送未编码的数据。此调用：

curl -XPOST -d 'Metadata/Type = "sas"' http://bms.org/bcknd/republish

将发送：

POST http://www.google.com/bcknd/republish HTTP/1.1
Host: www.google.com
User-Agent: curl/7.55.1
Accept: */*
Connection: Keep-Alive
Content-Length: 21
Content-Type: application/x-www-form-urlencoded

Metadata/Type = "sas"

如果应用了URL编码，/和"将被替换为其他字符。还要注意User-Agent和Accept标头

如果使用--data-urlencode，则将对该值进行URL编码：

POST http://www.google.com/bcknd/republish HTTP/1.1
Host: www.google.com
User-Agent: curl/7.55.1
Accept: */*
Connection: Keep-Alive
Content-Length: 27
Content-Type: application/x-www-form-urlencoded

Metadata/Type =%20%22sas%22

另一方面，这段代码：

static async Task Main(string[] args)
{
    var client=new HttpClient();
    var data = new FormUrlEncodedContent(new[] { new KeyValuePair<string, string>("Metadata/Type", "\"sas\""), });
    var response = await client.PostAsync("http://www.google.com/bcknd/republish", data);
    var  responseContent = response.Content;
    var body=await response.Content.ReadAsStringAsync();
    Console.WriteLine(body);
}

将发送：

POST http://www.google.com/bcknd/republish HTTP/1.1
Content-Type: application/x-www-form-urlencoded
Content-Length: 25
Host: www.google.com

Metadata%2FType=%22sas%22

要获得原始有效负载，可以使用带有手动编码内容的StringContent：

var data = new StringContent("Metadata/Type= \"sas\"",Encoding.UTF8,"application/x-www-form-urlencoded");

请求是：

POST http://www.google.com/bcknd/republish HTTP/1.1
Content-Type: application/x-www-form-urlencoded; charset=utf-8
Content-Length: 19
Host: www.google.com

Metadata/Type= "sas"

如果要发送User-Agent和Accept标头，可以将它们添加到每条单独的消息中或作为默认的请求标头：

var client=new HttpClient();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("*/*"));
client.DefaultRequestHeaders.UserAgent.Add(new ProductInfoHeaderValue("curl","7.55.1"));

这些将添加：

Accept: */*
User-Agent: curl/7.55.1

对请求

Answer 2

您可以使用HttpClient调用远程URL，如下所示

using (var httpClient = new HttpClient())
{
    using (var request = new HttpRequestMessage(new HttpMethod("POST"), "http://bms.org/bcknd/republish"))
    {
        request.Content = new StringContent("Metadata/Type = \"sas\"", Encoding.UTF8, "application/x-www-form-urlencoded");

        var response = await httpClient.SendAsync(request);
    }
}

在这里，我刚刚添加了参考代码，通过使用它，您可以创建自己的代码。我检查了你的curl请求和it seems issue it self。