cscの作法 その259

概要

cscの作法、調べてみた。
練習問題やってみた。

練習問題

httpプロトコルでエラーレスポンスを獲れ。

方針

• webclient使う
• try-catch使う
• Response使う

サンプルコード

using System.Collections;
using System.IO;
using System;
using System.Text;
using System.Net;

namespace app
{
	class test0 {
		static void Main() {
			ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;
			WebClient wc = new WebClient();
			string json = "{}";
			try
			{
				wc.Headers[HttpRequestHeader.ContentType] = "application/jose+json";
				//wc.Headers[HttpRequestHeader.ContentType] = "application/json";
				string response = wc.UploadString("https://acme-staging-v02.api.letsencrypt.org/acme/new-acct", "POST", json);
				Console.WriteLine(response);
			}
			catch (System.Net.WebException ex)
			{
				if (ex.Status == System.Net.WebExceptionStatus.ProtocolError)
				{
					System.Net.HttpWebResponse errres = (System.Net.HttpWebResponse) ex.Response;
					Console.WriteLine("{0}: {1}", errres.StatusCode, errres.StatusDescription);
					Console.WriteLine(ex.ToString());
					string responseText;
					using (var reader = new StreamReader(ex.Response.GetResponseStream()))
					{
						responseText = reader.ReadToEnd();
					}
					Console.WriteLine("WebException caught. Response text is {0}", responseText);
				}
				else
					Console.WriteLine(ex.Message);
			}
		}
	}
}

実行結果

>res0
BadRequest: Bad Request
System.Net.WebException: リモート サーバーがエラーを返しました: (400) 要求が不適切です
   場所 System.Net.WebClient.UploadDataInternal(Uri address, String method, Byte[] data, WebRequest& request)
   場所 System.Net.WebClient.UploadString(Uri address, String method, String data)
   場所 app.test0.Main()
WebException caught. Response text is {
  "type": "urn:ietf:params:acme:error:malformed",
  "detail": "Parse error reading JWS",
  "status": 400
}

>

以上。