fix: sometimes the IPFS server does not JSON encode an error

Author: richardschneider

src/IpfsClient.cs

@@ -252,6 +252,9 @@ HttpClient Api()
         /// <returns>
         ///   A string representation of the command's result.
         /// </returns>
+        /// <exception cref="HttpRequestException">
+        ///   When the IPFS server indicates an error.
+        /// </exception>
         public async Task<string> DoCommandAsync(string command, CancellationToken cancel, string arg = null, params string[] options)
         {
             var url = BuildCommand(command, arg, options);
@@ -294,6 +297,9 @@ public async Task<string> DoCommandAsync(string command, CancellationToken cance
         ///   The command's response is converted to <typeparamref name="T"/> using
         ///   <c>JsonConvert</c>.
         /// </remarks>
+        /// <exception cref="HttpRequestException">
+        ///   When the IPFS server indicates an error.
+        /// </exception>
         public async Task<T> DoCommandAsync<T>(string command, CancellationToken cancel, string arg = null, params string[] options)
         {
             var json = await DoCommandAsync(command, cancel, arg, options);
@@ -319,6 +325,9 @@ public async Task<T> DoCommandAsync<T>(string command, CancellationToken cancel,
         /// <returns>
         ///   A string representation of the command's result.
         /// </returns>
+        /// <exception cref="HttpRequestException">
+        ///   When the IPFS server indicates an error.
+        /// </exception>
         public async Task<string> PostCommandAsync(string command, CancellationToken cancel, string arg = null, params string[] options)
         {
             var url = BuildCommand(command, arg, options);
@@ -363,6 +372,9 @@ public async Task<string> PostCommandAsync(string command, CancellationToken can
         ///   The command's response is converted to <typeparamref name="T"/> using
         ///   <c>JsonConvert</c>.
         /// </remarks>
+        /// <exception cref="HttpRequestException">
+        ///   When the IPFS server indicates an error.
+        /// </exception>
         public async Task<T> PostCommandAsync<T>(string command, CancellationToken cancel, string arg = null, params string[] options)
         {
             var json = await PostCommandAsync(command, cancel, arg, options);
@@ -388,6 +400,9 @@ public async Task<T> PostCommandAsync<T>(string command, CancellationToken cance
         /// <returns>
         ///   A <see cref="Stream"/> containing the command's result.
         /// </returns>
+        /// <exception cref="HttpRequestException">
+        ///   When the IPFS server indicates an error.
+        /// </exception>
         public async Task<Stream> PostDownloadAsync(string command, CancellationToken cancel, string arg = null, params string[] options)
         {
             var url = BuildCommand(command, arg, options);
@@ -420,6 +435,9 @@ public async Task<Stream> PostDownloadAsync(string command, CancellationToken ca
         /// <returns>
         ///   A <see cref="Stream"/> containing the command's result.
         /// </returns>
+        /// <exception cref="HttpRequestException">
+        ///   When the IPFS server indicates an error.
+        /// </exception>
         public async Task<Stream> DownloadAsync(string command, CancellationToken cancel, string arg = null, params string[] options)
         {
             var url = BuildCommand(command, arg, options);
@@ -450,6 +468,9 @@ public async Task<Stream> DownloadAsync(string command, CancellationToken cancel
         /// <returns>
         ///   A byte array containing the command's result.
         /// </returns>
+        /// <exception cref="HttpRequestException">
+        ///   When the IPFS server indicates an error.
+        /// </exception>
         public async Task<byte[]> DownloadBytesAsync(string command, CancellationToken cancel, string arg = null, params string[] options)
         {
             var url = BuildCommand(command, arg, options);
@@ -470,6 +491,9 @@ public async Task<byte[]> DownloadBytesAsync(string command, CancellationToken c
         /// <param name="data"></param>
         /// <param name="options"></param>
         /// <returns></returns>
+        /// <exception cref="HttpRequestException">
+        ///   When the IPFS server indicates an error.
+        /// </exception>
         public async Task<String> UploadAsync(string command, CancellationToken cancel, Stream data, params string[] options)
         {
             var content = new MultipartFormDataContent();
@@ -513,13 +537,14 @@ public async Task<String> UploadAsync(string command, CancellationToken cancel,
             }
         }
 
-
-
         /// <summary>
-        /// 
+        ///   Throws an <see cref="HttpRequestException"/> if the response
+        ///   does not indicate success.
         /// </summary>
         /// <param name="response"></param>
-        /// <returns></returns>
+        /// <returns>
+        ///    <b>true</b>
+        /// </returns>
         /// <remarks>
         ///   The API server returns an JSON error in the form <c>{ "Message": "...", "Code": ... }</c>.
         /// </remarks>
@@ -538,7 +563,12 @@ async Task<bool> ThrowOnErrorAsync(HttpResponseMessage response)
             var body = await response.Content.ReadAsStringAsync();
             if (log.IsDebugEnabled)
                 log.Debug("ERR " + body);
-            var message = (string)JsonConvert.DeserializeObject<dynamic>(body).Message;
+            string message = body;
+            try
+            {
+                message = (string)JsonConvert.DeserializeObject<dynamic>(body).Message;
+            }
+            catch { }
             throw new HttpRequestException(message);
         }
 

test/IpfsClientTest.cs

@@ -1,6 +1,7 @@
 using Ipfs.Api;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using System;
+using System.Net.Http;
 using System.Threading;
 
 namespace Ipfs.Api
@@ -28,8 +29,15 @@ public void Do_Command_Throws_Exception_On_Invalid_Command()
         {
             IpfsClient target = TestFixture.Ipfs;
             object unknown;
-            ExceptionAssert.Throws<Exception>(() => unknown = target.DoCommandAsync("foobar", default(CancellationToken)).Result);
+            ExceptionAssert.Throws<HttpRequestException>(() => unknown = target.DoCommandAsync("foobar", default(CancellationToken)).Result);
         }
 
+        [TestMethod]
+        public void Do_Command_Throws_Exception_On_Missing_Argument()
+        {
+            IpfsClient target = TestFixture.Ipfs;
+            object unknown;
+            ExceptionAssert.Throws<HttpRequestException>(() => unknown = target.DoCommandAsync("key/gen", default(CancellationToken)).Result);
+        }
     }
 }