Protocol fix. Updated README.

README.md

@@ -1,4 +1,4 @@
-# Synopsis
+# Overview
 
 The package provides a tool to send data to Zabbix in the same way as [zabbix_sender](https://www.zabbix.com/documentation/4.0/ru/manual/concepts/sender) tool. It implements [Zabbix Sender Protocol 4.0](https://www.zabbix.org/wiki/Docs/protocols/zabbix_sender/4.0).
 
@@ -14,7 +14,11 @@ PM> Install-Package ZabbixSender.Async
 
 ```C#
 var sender = new ZabbixSender.Async.Sender("192.168.0.10");
-var response = sender.Send("MonitoredHost1", "trapper.item1", "10");
+var response = sender.Send("MonitoredHost1", "trapper.item1", "12");
 Console.WriteLine(reponse.Response); // "success" or "fail"
 Console.WriteLine(response.Info);    // e.g. "Processed 1 Failed 0 Total 1 Seconds spent 0.000253"
-```
+```
+
+# Remarks
+
+Note, that in order for the request to be accepted, hosts like `MonitoredHost1` above, should be [configured](https://www.zabbix.com/documentation/4.0/manual/config/hosts/host). The same should do the items (like `trapper.item1` above). The item type should have [Zabbix trapper](https://www.zabbix.com/documentation/4.0/manual/config/items/itemtypes/trapper). Also the values passed (`12` above) should respect the type of information, configured for each item.

ZabbixSender.Async/Formatter.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Linq;
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
@@ -104,48 +105,44 @@ await stream.WriteAsync(BitConverter.GetBytes(ms.Length), 0,
 
         public SenderResponse ReadResponse(Stream stream)
         {
-            int responseSize = Math.Max(bufferSize, 128);
-            var response = new byte[responseSize];
-            var count = stream.Read(response, 0, response.Length);
-            var begin = Array.IndexOf(response, (byte)'{');
-
-            if (count <= 0)
-                throw new ProtocolException("empty reponse received");
+            try
+            {
+                var buffer = new byte[13];
 
-            if (begin == -1)
-                throw new ProtocolException("start of Json ({) not found", response);
+                stream.Read(buffer, 0, buffer.Length); // skip the length
 
-            if (count >= responseSize)
-                throw new ProtocolException("the response is too big", response);
+                if (ZabbixHeader.Zip(buffer, (x, y) => x != y).Any(b => b))
+                    throw new ProtocolException("the response has an incorrect header");
 
-            try
-            {
-                using (var ms = new MemoryStream(response, begin, count - begin))
-                {
-                    using (var reader = new StreamReader(ms, Encoding.ASCII))
-                    using (var jsonReader = new JsonTextReader(reader))
-                        return serializer.Deserialize<SenderResponse>(jsonReader);
-                }
+                using (var reader = new StreamReader(stream, Encoding.ASCII))
+                using (var jsonReader = new JsonTextReader(reader))
+                    return serializer.Deserialize<SenderResponse>(jsonReader);
             }
             catch (JsonException ex)
             {
-                throw new ProtocolException("invalid response format", ex, response);
+                throw new ProtocolException("invalid response format", ex);
             }
         }
 
-        public async Task<SenderResponse> ReadResponseAsync(Stream stream,
-            CancellationToken cancellationToken)
+        public async Task<SenderResponse> ReadResponseAsync(Stream stream, CancellationToken cancellationToken)
         {
-            var response = new byte[1024];
-            var count = await stream.ReadAsync(response, 0, response.Length, cancellationToken);
-            var begin = Array.IndexOf(response, (byte)'{');
-
-            using (var ms = new MemoryStream(response, begin, count - begin))
+            try
             {
-                using (var reader = new StreamReader(ms, Encoding.ASCII))
+                var buffer = new byte[13];
+
+                await stream.ReadAsync(buffer, 0, buffer.Length, cancellationToken); // skip the length
+
+                if (ZabbixHeader.Zip(buffer, (x, y) => x != y).Any(b => b))
+                    throw new ProtocolException("the response has an incorrect header");
+
+                using (var reader = new StreamReader(stream, Encoding.ASCII))
                 using (var jsonReader = new JsonTextReader(reader))
                     return serializer.Deserialize<SenderResponse>(jsonReader);
             }
+            catch (JsonException ex)
+            {
+                throw new ProtocolException("invalid response format", ex);
+            }
         }
     }
 }

ZabbixSender.Async/ProtocolException.cs

@@ -11,17 +11,5 @@ public ProtocolException(string message) :
         public ProtocolException(string message, Exception innerException) :
             base($"Protocol error - {message}.", innerException)
         { }
-
-        public ProtocolException(string message, byte[] response) :
-            base($"Protocol error - {message}. See the whole response in Data property by Response key.")
-        {
-            Data.Add("Response", response);
-        }
-
-        public ProtocolException(string message, Exception innerException, byte[] response) :
-            base($"Protocol error - {message}. See the whole response in Data property by Response key.", innerException)
-        {
-            Data.Add("Response", response);
-        }
     }
 }

ZabbixSender.Async/ZabbixSender.Async.csproj

@@ -2,13 +2,13 @@
 
   <PropertyGroup>
     <TargetFrameworks>netcoreapp2.1;net461</TargetFrameworks>
-    <Version>1.0.1</Version>
+    <Version>1.0.2</Version>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <Copyright>Apache License 2.0 (stop-cran, 2018)</Copyright>
     <Authors>stop-cran &lt;[email protected]&gt;</Authors>
     <Company>stop-cran &lt;[email protected]&gt;</Company>
     <RepositoryUrl>https://github.com/stop-cran/ZabbixSender.Async</RepositoryUrl>
-    <PackageReleaseNotes>Added clock. Added interfaces for a possibility of DI.</PackageReleaseNotes>
+    <PackageReleaseNotes>Protocol fix.</PackageReleaseNotes>
     <Description>The package provides a tool to send data to Zabbix in the same way as zabbix_sender tool. It implements Zabbix Sender Protocol 4.0.</Description>
   </PropertyGroup>