Allow request timeout to be set

src/AvaTaxClient.cs

@@ -4,6 +4,7 @@
 using System.Linq;
 using System.Net.Http;
 using System.Threading.Tasks;
+using System.Threading;
 using System.Runtime.ExceptionServices;
 #endif
 using System.Net;
@@ -23,10 +24,15 @@ namespace Avalara.AvaTax.RestClient
     /// </remarks>
     public partial class AvaTaxClient
     {
+        private AvaTaxClientOptions _options = new AvaTaxClientOptions();
         private Dictionary<string, string> _clientHeaders = new Dictionary<string, string>();
         private Uri _envUri;
 #if PORTABLE
-        private static HttpClient _client = new HttpClient() { Timeout = TimeSpan.FromMinutes(20) };
+        private static HttpClient _client = new HttpClient() 
+        {
+            // This timeout will be the default timeout used for all requests if if a timeout is not provided with the AvaTaxClientOptions
+            Timeout = TimeSpan.FromMinutes(20) 
+        };
 #endif
 
         /// <summary>
@@ -81,9 +87,9 @@ public AvaTaxClient(string appName, string appVersion, string machineName, Uri c
             WithClientIdentifier(appName, appVersion, machineName);
             _envUri = customEnvironment;
         }
-#endregion
+        #endregion
 
-#region Security
+        #region Security
         /// <summary>
         /// Sets the default security header string
         /// </summary>
@@ -165,9 +171,20 @@ public AvaTaxClient WithClientIdentifier(string appName, string appVersion, stri
             _clientHeaders.Add(Constants.AVALARA_CLIENT_HEADER, String.Format("{0}; {1}; {2}; {3}; {4}", appName, appVersion, "CSharpRestClient", API_VERSION, machineName));
             return this;
         }
-#endregion
+        #endregion
+
+        /// <summary>
+        /// Sets options for the AvaTaxClient and how it behaves.
+        /// </summary>
+        /// <param name="options"></param>
+        /// <returns></returns>
+        public AvaTaxClient WithOptions(AvaTaxClientOptions options)
+        {
+            _options = options ?? new AvaTaxClientOptions();
+            return this;
+        }
 
-#region REST Call Interface
+        #region REST Call Interface
 #if PORTABLE
         /// <summary>
         /// Implementation of asynchronous client APIs
@@ -236,9 +253,9 @@ public FileResult RestCallFile(string verb, AvaTaxPath relativePath, object payl
             }
         }
 #endif
-#endregion
+        #endregion
 
-#region Implementation
+        #region Implementation
         private JsonSerializerSettings _serializer_settings = null;
         private JsonSerializerSettings SerializerSettings
         {
@@ -354,7 +371,27 @@ private async Task<HttpResponseMessage> InternalRestCallAsync(CallDuration cd, s
                 // Send
                 cd.FinishSetup();
 
-                return await _client.SendAsync(request).ConfigureAwait(false);
+                CancellationTokenSource timeoutTokenSource = null;
+
+                try
+                {
+                    CancellationToken token = default(CancellationToken);
+                    if (_options != null && _options.Timeout.HasValue)
+                    {
+                        timeoutTokenSource = new CancellationTokenSource(_options.Timeout.Value);
+                        token = timeoutTokenSource.Token;
+                    } 
+
+                    return await _client.SendAsync(request, token).ConfigureAwait(false);
+                }
+                finally
+                {
+                    if (timeoutTokenSource != null)
+                    {
+                        timeoutTokenSource.Dispose();
+                        timeoutTokenSource = null;
+                    }
+                }                
             }
         }        
 
@@ -482,7 +519,13 @@ private FileResult RestCallFile(string verb, AvaTaxPath relativePath, object con
             // Use HttpWebRequest so we can get a decent response
             var wr = (HttpWebRequest)WebRequest.Create(path);
             wr.Proxy = null;
+
+            // Default to 20 minutes if a timeout has not been provided in the AvaTaxClientOptions. 
             wr.Timeout = 1200000;
+            if (_options != null && _options.Timeout.HasValue)
+            {
+                wr.Timeout = Convert.ToInt32(Math.Floor(_options.Timeout.Value.TotalMilliseconds));
+            }
 
             // Add headers
             foreach (var key in _clientHeaders.Keys)
@@ -515,7 +558,7 @@ private FileResult RestCallFile(string verb, AvaTaxPath relativePath, object con
                     using (var inStream = response.GetResponseStream()) {
                         const int BUFFER_SIZE = 1024;
                         var chunks = new List<byte>();
-                        var totalBytes = 0; 
+                        var totalBytes = 0;
                         var bytesRead = 0;
 
                         do
@@ -531,7 +574,7 @@ private FileResult RestCallFile(string verb, AvaTaxPath relativePath, object con
                             }
                             totalBytes += bytesRead;
                         } while (bytesRead > 0);
-        
+
                         if(totalBytes <= 0) {
                             throw new IOException("Response contained no data");
                         }
@@ -593,6 +636,11 @@ private string RestCallString(string verb, AvaTaxPath relativePath, object conte
             wr.Proxy = null;
             wr.Timeout = 1200000;
 
+            if (_options != null && _options.Timeout.HasValue)
+            {
+                wr.Timeout = Convert.ToInt32(Math.Floor(_options.Timeout.Value.TotalMilliseconds));
+            }
+
             // Add headers
             foreach (var key in _clientHeaders.Keys)
             {
@@ -655,7 +703,7 @@ private string RestCallString(string verb, AvaTaxPath relativePath, object conte
                     }
                 }
 
-            // Catch a web exception
+                // Catch a web exception
             } catch (WebException webex) {
                 HttpWebResponse httpWebResponse = webex.Response as HttpWebResponse;
                 if (httpWebResponse != null) {

src/AvaTaxClientOptions.cs

@@ -0,0 +1,21 @@
+using System;
+#if PORTABLE
+using System.Linq;
+using System.Net.Http;
+using System.Threading.Tasks;
+using System.Threading;
+#endif
+
+namespace Avalara.AvaTax.RestClient
+{
+    /// <summary>
+    /// Configuration options for the <see cref="AvaTaxClient"/>
+    /// </summary>
+    public class AvaTaxClientOptions
+    {
+        /// <summary>
+        /// The request timeout.
+        /// </summary>
+        public TimeSpan? Timeout { get; set; }
+    }
+}

src/Avalara.AvaTax.net20.csproj

@@ -54,6 +54,7 @@
     <Compile Include="AvaTaxApi.cs" />
     <Compile Include="AvaTaxCallEventArgs.cs" />
     <Compile Include="AvaTaxClient.cs" />
+    <Compile Include="AvaTaxClientOptions.cs" />
     <Compile Include="AvaTaxEnvironment.cs" />
     <Compile Include="AvaTaxError.cs" />
     <Compile Include="AvaTaxOfflineHelper.cs" />

src/Avalara.AvaTax.net45.csproj

@@ -59,6 +59,7 @@
     <Compile Include="AvaTaxApi.cs" />
     <Compile Include="AvaTaxCallEventArgs.cs" />
     <Compile Include="AvaTaxClient.cs" />
+    <Compile Include="AvaTaxClientOptions.cs" />
     <Compile Include="AvaTaxEnvironment.cs" />
     <Compile Include="AvaTaxError.cs" />
     <Compile Include="AvaTaxOfflineHelper.cs" />