Merge pull request #124 from lwdeveloper/empty-headers-dictionary

Handle empty headers on inbound webhooks

src/Mandrill.net/Model/WebHook/MandrillInboundMessageInfo.cs

@@ -1,5 +1,8 @@
 using System;
 using System.Collections.Generic;
+using Mandrill.net.Serialization;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
 
 namespace Mandrill.Model
 {
@@ -13,6 +16,8 @@ public class MandrillInboundMessageInfo
 
         public string FromName { get; set; }
 
+        /// Inbound webhooks contain either a dictionary or an empty array for the headers property
+        [JsonConverter(typeof(EmptyArrayOrDictionaryConverter))]
         public Dictionary<string, object> Headers { get; set; } = new Dictionary<string, object>(StringComparer.OrdinalIgnoreCase);
 
         public string Html { get; set; }

src/Mandrill.net/Serialization/EmptyArrayOrDictionaryConverter.cs

@@ -0,0 +1,47 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+
+namespace Mandrill.net.Serialization
+{
+    /// <summary>
+    /// This converter will allow an empty array to be converted to a dictionary
+    /// </summary>
+    internal class EmptyArrayOrDictionaryConverter : JsonConverter
+    {
+        public override bool CanConvert(Type objectType)
+        {
+            return objectType.IsAssignableFrom(typeof(Dictionary<string, object>));
+        }
+
+        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
+        {
+            JToken token = JToken.Load(reader);
+
+            if (token.Type == JTokenType.Object)
+            {
+                return token.ToObject(objectType);
+            }
+            else if (token.Type == JTokenType.Array)
+            {
+                if (!token.HasValues)
+                {
+                    // Create empty dictionary
+                    return Activator.CreateInstance(objectType);
+                }
+            }
+
+            throw new JsonSerializationException("Object or empty array expected");
+        }
+
+        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
+        {
+            serializer.Serialize(writer, value);
+        }
+    }
+
+}

src/Mandrill.net/Serialization/MandrillJsonContractResolver.cs

@@ -46,7 +46,6 @@ protected override JsonProperty CreateProperty(MemberInfo member, MemberSerializ
                         var dictionary = prop.GetValue(instance) as IDictionary<string, string>;
                         return dictionary?.Count > 0;
                     };
-
                 }
 
                 if (typeof(IDictionary<string, object>).GetTypeInfo().IsAssignableFrom(propertyType.GetTypeInfo()))

tests/SerializationTests.cs

@@ -457,7 +457,21 @@ public void Can_serialize_inbound_web_hook()
             events[1].Msg.FromName.Should().BeNullOrEmpty();
 
             Output.WriteLine(JArray.FromObject(events, MandrillSerializer.Instance).ToString());
+        }
+
+        [Fact]
+        public void Can_serialize_inbound_web_hook_with_empty_headers()
+        {
+            string json = TestData.mandrill_inbound_empty_headers;
+
+            var events = MandrillInboundEvent.ParseMandrillEvents(json);
 
+            events.Should().NotBeNullOrEmpty();
+            events.Should().HaveCount(1);
+
+            events[0].Msg.Headers.Should().BeEmpty();
+
+            Output.WriteLine(JArray.FromObject(events, MandrillSerializer.Instance).ToString());
         }
 
         [Fact]
@@ -474,7 +488,6 @@ public void Can_serialize_sync_web_hook()
             events[0].Type.Should().Be(MandrillSyncType.Blacklist);
         }
 
-
         [Fact]
         public void Can_serialize_case_insensitive_header_dictionary()
         {

tests/TestData.cs

@@ -294,6 +294,50 @@ public class TestData
 
         #endregion
 
+        #region mandrill_inbound_empty_headers
+
+        public const string mandrill_inbound_empty_headers = @"[
+    {
+        ""event"": ""inbound"",
+        ""msg"": {
+            ""dkim"": {
+                ""signed"": true,
+                ""valid"": true
+            },
+            ""email"": ""[email protected]"",
+            ""from_email"": ""[email protected]"",
+            ""from_name"": ""Example Sender"",
+            ""headers"": [],
+            ""html"": ""<p>This is an example inbound message.</p><img src=\""http://mandrillapp.com/track/open.php?u=999&id=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa&tags=_all,[email protected]\"" height=\""1\"" width=\""1\"">\n"",
+            ""raw_msg"": ""Received: from mail115.us4.mandrillapp.com (mail115.us4.mandrillapp.com [205.201.136.115])\n\tby mail.example.com (Postfix) with ESMTP id AAAAAAAAAAA\n\tfor <[email protected]>; Fri, 10 May 2013 19:28:20 +0000 (UTC)\nDKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; s=mandrill; d=mail115.us4.mandrillapp.com;\n h=From:Sender:Subject:List-Unsubscribe:To:Message-Id:Date:MIME-Version:Content-Type; [email protected];\n bh=d60x72jf42gLILD7IiqBL0OBb40=;\n b=iJd7eBugdIjzqW84UZ2xynlg1SojANJR6xfz0JDD44h78EpbqJiYVcMIfRG7mkrn741Bd5YaMR6p\n 9j41OA9A5am+8BE1Ng2kLRGwou5hRInn+xXBAQm2NUt5FkoXSpvm4gC4gQSOxPbQcuzlLha9JqxJ\n 8ZZ89/20txUrRq9cYxk=\nDomainKey-Signature: a=rsa-sha1; c=nofws; q=dns; s=mandrill; d=mail115.us4.mandrillapp.com;\n b=X6qudHd4oOJvVQZcoAEUCJgB875SwzEO5UKf6NvpfqyCVjdaO79WdDulLlfNVELeuoK2m6alt2yw\n 5Qhp4TW5NegyFf6Ogr/Hy0Lt411r/0lRf0nyaVkqMM/9g13B6D9CS092v70wshX8+qdyxK8fADw8\n kEelbCK2cEl0AGIeAeo=;\nReceived: from localhost (127.0.0.1) by mail115.us4.mandrillapp.com id hhl55a14i282 for <[email protected]>; Fri, 10 May 2013 19:28:20 +0000 (envelope-from <bounce-md_999.aaaaaaaa.v1-aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa@mail115.us4.mandrillapp.com>)\nDKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=c.mandrillapp.com; \n [email protected]; q=dns/txt; s=mandrill; t=1368214100; h=From : \n Sender : Subject : List-Unsubscribe : To : Message-Id : Date : \n MIME-Version : Content-Type : From : Subject : Date : X-Mandrill-User : \n List-Unsubscribe; bh=y5Vz+RDcKZmWzRc9s0xUJR6k4APvBNktBqy1EhSWM8o=; \n b=PLAUIuw8zk8kG5tPkmcnSanElxt6I5lp5t32nSvzVQE7R8u0AmIEjeIDZEt31+Q9PWt+nY\n sHHRsXUQ9SZpndT9Bk++/SmyA2ntU/2AKuqDpPkMZiTqxmGF80Wz4JJgx2aCEB1LeLVmFFwB\n 5Nr/LBSlsBlRcjT9QiWw0/iRvCn74=\nFrom: <[email protected]>\nSender: <[email protected]>\nSubject: This is an example webhook message\nList-Unsubscribe: <mailto:unsubscribe-md_999.aaaaaaaa.v1-aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa@mailin1.us2.mcsv.net?subject=unsub>\nTo: <[email protected]>\nX-Report-Abuse: Please forward a copy of this message, including all headers, to [email protected]\nX-Mandrill-User: md_999\nMessage-Id: <999.20130510192820.aaaaaaaaaaaaaa.aaaaaaaa@mail115.us4.mandrillapp.com>\nDate: Fri, 10 May 2013 19:28:20 +0000\nMIME-Version: 1.0\nContent-Type: multipart/alternative; boundary=\""_av-7r7zDhHxVEAo2yMWasfuFw\""\n\n--_av-7r7zDhHxVEAo2yMWasfuFw\nContent-Type: text/plain; charset=utf-8\nContent-Transfer-Encoding: 7bit\n\nThis is an example inbound message.\n--_av-7r7zDhHxVEAo2yMWasfuFw\nContent-Type: text/html; charset=utf-8\nContent-Transfer-Encoding: 7bit\n\n<p>This is an example inbound message.</p><img src=\""http://mandrillapp.com/track/open.php?u=999&id=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa&tags=_all,[email protected]\"" height=\""1\"" width=\""1\"">\n--_av-7r7zDhHxVEAo2yMWasfuFw--"",
+            ""sender"": null,
+            ""spam_report"": {
+                ""matched_rules"": [],
+                ""score"": 0
+            },
+            ""spf"": {
+                ""detail"": ""sender SPF authorized"",
+                ""result"": ""pass""
+            },
+            ""subject"": ""This is an example webhook message"",
+            ""tags"": [],
+            ""template"": null,
+            ""text"": ""This is an example inbound message.\n"",
+            ""text_flowed"": false,
+            ""to"": [
+                        [
+                            ""[email protected]"",
+                            null
+                        ]
+            ],
+            ""cc"": []
+        },
+        ""ts"": 1368214102
+    }
+]";
+
+        #endregion
+
         #region mandrill_webhook_example
 
         public const string mandrill_webhook_example = @"[