Basic Websocket support working, without authentication (auth broken)

ntfysh_client/MainForm.cs

@@ -34,7 +34,14 @@ namespace ntfysh_client
             if (result != DialogResult.OK) return;
                 
             //Subscribe
-            _notificationListener.SubscribeToTopicUsingLongHttpJson(dialog.Unique, dialog.TopicId, dialog.ServerUrl, dialog.Username, dialog.Password);
+            if (dialog.UseWebsockets)
+            {
+                _notificationListener.SubscribeToTopicUsingWebsocket(dialog.Unique, dialog.TopicId, dialog.ServerUrl, dialog.Username, dialog.Password);
+            }
+            else
+            {
+                _notificationListener.SubscribeToTopicUsingLongHttpJson(dialog.Unique, dialog.TopicId, dialog.ServerUrl, dialog.Username, dialog.Password);
+            }
 
             //Add to the user visible list
             notificationTopics.Items.Add(dialog.Unique);
@@ -167,7 +174,24 @@ namespace ntfysh_client
             //Load them in
             foreach (SubscribedTopic topic in topics)
             {
-                _notificationListener.SubscribeToTopicUsingLongHttpJson($"{topic.TopicId}@{topic.ServerUrl}", topic.TopicId, topic.ServerUrl, topic.Username, topic.Password);
+                string[] parts = topic.ServerUrl.Split("://", 2);
+                
+                switch (parts[0].ToLower())
+                {
+                    case "ws":
+                    case "wss":
+                        _notificationListener.SubscribeToTopicUsingWebsocket($"{topic.TopicId}@{topic.ServerUrl}", topic.TopicId, topic.ServerUrl, topic.Username, topic.Password);
+                        break;
+                    
+                    case "http":
+                    case "https":
+                        _notificationListener.SubscribeToTopicUsingLongHttpJson($"{topic.TopicId}@{topic.ServerUrl}", topic.TopicId, topic.ServerUrl, topic.Username, topic.Password);
+                        break;
+                    
+                    default:
+                        continue;
+                }
+                
                 notificationTopics.Items.Add($"{topic.TopicId}@{topic.ServerUrl}");
             }
         }

ntfysh_client/NotificationListener.cs

@@ -31,7 +31,7 @@ namespace ntfysh_client
             ServicePointManager.DefaultConnectionLimit = 100;
         }
 
-        private async Task ListenToTopicAsync(HttpRequestMessage message, CancellationToken cancellationToken)
+        private async Task ListenToTopicWithHttpLongJsonAsync(HttpRequestMessage message, CancellationToken cancellationToken)
         {
             if (_isDisposed) throw new ObjectDisposedException(nameof(NotificationListener));
             
@@ -84,6 +84,59 @@ namespace ntfysh_client
             }
         }
         
+        private async Task ListenToTopicWithWebsocketAsync(Uri uri, NetworkCredential credentials, CancellationToken cancellationToken)
+        {
+            if (_isDisposed) throw new ObjectDisposedException(nameof(NotificationListener));
+            
+            while (!cancellationToken.IsCancellationRequested)
+            {
+                using ClientWebSocket socket = new();
+                socket.Options.Credentials = credentials;
+                
+                try
+                {
+                    StringBuilder mainBuffer = new();
+                    
+                    await socket.ConnectAsync(uri, cancellationToken);
+                    
+                    while (!cancellationToken.IsCancellationRequested)
+                    {
+                        //Read as much as possible
+                        byte[] buffer = new byte[8192];
+                        WebSocketReceiveResult? result = await socket.ReceiveAsync(new ArraySegment<byte>(buffer), cancellationToken);
+                        
+                        //Append it to our main buffer
+                        mainBuffer.Append(Encoding.UTF8.GetString(buffer, 0, result.Count));
+                        
+                        List<string> lines = mainBuffer.ToString().Split('\n').ToList();
+                        //If we have not yet received a full line, meaning theres only 1 part, go back to reading
+                        if (lines.Count <= 1) continue;
+                        
+                        //We now have at least 1 line! Count how many full lines. There will always be a partial line at the end, even if that partial line is empty
+                        //Separate the partial line from the full lines
+                        int partialLineIndex = lines.Count - 1;
+                        string partialLine = lines[partialLineIndex];
+                        lines.RemoveAt(partialLineIndex);
+                        
+                        //Process the full lines
+                        foreach (string line in lines) ProcessMessage(line);
+                        
+                        //Write back the partial line
+                        mainBuffer.Clear();
+                        mainBuffer.Append(partialLine);
+                    }
+                }
+                catch (Exception ex)
+                {
+                    #if DEBUG
+                        Debug.WriteLine(ex);
+                    #endif
+                    
+                    //Fall back to the outer loop to restart the listen, or cancel if requested
+                }
+            }
+        }
+
         private void ProcessMessage(string message)
         {
             #if DEBUG
@@ -120,11 +173,26 @@ namespace ntfysh_client
             }
 
             CancellationTokenSource listenCanceller = new();
-            Task listenTask = ListenToTopicAsync(message, listenCanceller.Token);
+            Task listenTask = ListenToTopicWithHttpLongJsonAsync(message, listenCanceller.Token);
 
             SubscribedTopicsByUnique.Add(unique, new SubscribedTopic(topicId, serverUrl, username, password, listenTask, listenCanceller));
         }
         
+        public void SubscribeToTopicUsingWebsocket(string unique, string topicId, string serverUrl, string? username, string? password)
+        {
+            if (_isDisposed) throw new ObjectDisposedException(nameof(NotificationListener));
+            
+            if (SubscribedTopicsByUnique.ContainsKey(unique)) throw new InvalidOperationException("A topic with this unique already exists");
+            
+            if (string.IsNullOrWhiteSpace(username)) username = null;
+            if (string.IsNullOrWhiteSpace(password)) password = null;
+            
+            Uri targetUri = new($"{serverUrl}/{HttpUtility.UrlEncode(topicId)}/ws");
+            CancellationTokenSource listenCanceller = new();
+            Task listenTask = ListenToTopicWithWebsocketAsync(targetUri, new NetworkCredential(username, password), listenCanceller.Token);
+            SubscribedTopicsByUnique.Add(unique, new SubscribedTopic(topicId, serverUrl, username, password, listenTask, listenCanceller));
+        }
+
         public async Task UnsubscribeFromTopicAsync(string topicUniqueString)
         {
             if (_isDisposed) throw new ObjectDisposedException(nameof(NotificationListener));

ntfysh_client/SubscribeDialog.Designer.cs

@@ -40,6 +40,8 @@ namespace ntfysh_client
             this.label3 = new System.Windows.Forms.Label();
             this.password = new System.Windows.Forms.TextBox();
             this.label4 = new System.Windows.Forms.Label();
+            this.label5 = new System.Windows.Forms.Label();
+            this.connectionType = new System.Windows.Forms.ComboBox();
             this.panel1.SuspendLayout();
             this.SuspendLayout();
             // 
@@ -49,18 +51,19 @@ namespace ntfysh_client
             this.panel1.Controls.Add(this.button2);
             this.panel1.Controls.Add(this.button1);
             this.panel1.Dock = System.Windows.Forms.DockStyle.Bottom;
-            this.panel1.Location = new System.Drawing.Point(0, 175);
+            this.panel1.Location = new System.Drawing.Point(0, 244);
+            this.panel1.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
             this.panel1.Name = "panel1";
-            this.panel1.Size = new System.Drawing.Size(297, 44);
+            this.panel1.Size = new System.Drawing.Size(346, 51);
             this.panel1.TabIndex = 0;
             // 
             // button2
             // 
             this.button2.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
-            this.button2.Location = new System.Drawing.Point(131, 11);
+            this.button2.Location = new System.Drawing.Point(153, 13);
-            this.button2.Margin = new System.Windows.Forms.Padding(10, 10, 3, 10);
+            this.button2.Margin = new System.Windows.Forms.Padding(12, 12, 4, 12);
             this.button2.Name = "button2";
-            this.button2.Size = new System.Drawing.Size(75, 23);
+            this.button2.Size = new System.Drawing.Size(88, 27);
             this.button2.TabIndex = 1;
             this.button2.Text = "Cancel";
             this.button2.UseVisualStyleBackColor = true;
@@ -69,10 +72,10 @@ namespace ntfysh_client
             // button1
             // 
             this.button1.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
-            this.button1.Location = new System.Drawing.Point(212, 11);
+            this.button1.Location = new System.Drawing.Point(247, 13);
-            this.button1.Margin = new System.Windows.Forms.Padding(3, 10, 10, 10);
+            this.button1.Margin = new System.Windows.Forms.Padding(4, 12, 12, 12);
             this.button1.Name = "button1";
-            this.button1.Size = new System.Drawing.Size(75, 23);
+            this.button1.Size = new System.Drawing.Size(88, 27);
             this.button1.TabIndex = 2;
             this.button1.Text = "Subscribe";
             this.button1.UseVisualStyleBackColor = true;
@@ -81,9 +84,10 @@ namespace ntfysh_client
             // label1
             // 
             this.label1.AutoSize = true;
-            this.label1.Location = new System.Drawing.Point(12, 9);
+            this.label1.Location = new System.Drawing.Point(14, 10);
+            this.label1.Margin = new System.Windows.Forms.Padding(4, 0, 4, 0);
             this.label1.Name = "label1";
-            this.label1.Size = new System.Drawing.Size(51, 13);
+            this.label1.Size = new System.Drawing.Size(52, 15);
             this.label1.TabIndex = 1;
             this.label1.Text = "Topic ID:";
             // 
@@ -91,9 +95,10 @@ namespace ntfysh_client
             // 
             this.topicId.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
             | System.Windows.Forms.AnchorStyles.Right)));
-            this.topicId.Location = new System.Drawing.Point(12, 25);
+            this.topicId.Location = new System.Drawing.Point(14, 29);
+            this.topicId.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
             this.topicId.Name = "topicId";
-            this.topicId.Size = new System.Drawing.Size(273, 20);
+            this.topicId.Size = new System.Drawing.Size(318, 23);
             this.topicId.TabIndex = 0;
             this.topicId.KeyDown += new System.Windows.Forms.KeyEventHandler(this.topicId_KeyDown);
             // 
@@ -101,19 +106,21 @@ namespace ntfysh_client
             // 
             this.serverUrl.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
             | System.Windows.Forms.AnchorStyles.Right)));
-            this.serverUrl.Location = new System.Drawing.Point(12, 64);
+            this.serverUrl.Location = new System.Drawing.Point(14, 74);
+            this.serverUrl.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
             this.serverUrl.Name = "serverUrl";
-            this.serverUrl.Size = new System.Drawing.Size(273, 20);
+            this.serverUrl.Size = new System.Drawing.Size(318, 23);
             this.serverUrl.TabIndex = 2;
-            this.serverUrl.Text = "https://ntfy.sh";
+            this.serverUrl.Text = "wss://ntfy.sh";
             this.serverUrl.KeyDown += new System.Windows.Forms.KeyEventHandler(this.serverUrl_KeyDown);
             // 
             // label2
             // 
             this.label2.AutoSize = true;
-            this.label2.Location = new System.Drawing.Point(10, 48);
+            this.label2.Location = new System.Drawing.Point(12, 55);
+            this.label2.Margin = new System.Windows.Forms.Padding(4, 0, 4, 0);
             this.label2.Name = "label2";
-            this.label2.Size = new System.Drawing.Size(66, 13);
+            this.label2.Size = new System.Drawing.Size(66, 15);
             this.label2.TabIndex = 3;
             this.label2.Text = "Server URL:";
             // 
@@ -121,18 +128,20 @@ namespace ntfysh_client
             // 
             this.username.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
             | System.Windows.Forms.AnchorStyles.Right)));
-            this.username.Location = new System.Drawing.Point(12, 103);
+            this.username.Location = new System.Drawing.Point(14, 119);
+            this.username.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
             this.username.Name = "username";
-            this.username.Size = new System.Drawing.Size(273, 20);
+            this.username.Size = new System.Drawing.Size(318, 23);
             this.username.TabIndex = 4;
             this.username.KeyDown += new System.Windows.Forms.KeyEventHandler(this.username_KeyDown);
             // 
             // label3
             // 
             this.label3.AutoSize = true;
-            this.label3.Location = new System.Drawing.Point(10, 87);
+            this.label3.Location = new System.Drawing.Point(12, 100);
+            this.label3.Margin = new System.Windows.Forms.Padding(4, 0, 4, 0);
             this.label3.Name = "label3";
-            this.label3.Size = new System.Drawing.Size(58, 13);
+            this.label3.Size = new System.Drawing.Size(63, 15);
             this.label3.TabIndex = 5;
             this.label3.Text = "Username:";
             // 
@@ -140,9 +149,10 @@ namespace ntfysh_client
             // 
             this.password.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
             | System.Windows.Forms.AnchorStyles.Right)));
-            this.password.Location = new System.Drawing.Point(12, 142);
+            this.password.Location = new System.Drawing.Point(14, 164);
+            this.password.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
             this.password.Name = "password";
-            this.password.Size = new System.Drawing.Size(273, 20);
+            this.password.Size = new System.Drawing.Size(318, 23);
             this.password.TabIndex = 6;
             this.password.UseSystemPasswordChar = true;
             this.password.KeyDown += new System.Windows.Forms.KeyEventHandler(this.password_KeyDown);
@@ -150,18 +160,44 @@ namespace ntfysh_client
             // label4
             // 
             this.label4.AutoSize = true;
-            this.label4.Location = new System.Drawing.Point(10, 126);
+            this.label4.Location = new System.Drawing.Point(12, 145);
+            this.label4.Margin = new System.Windows.Forms.Padding(4, 0, 4, 0);
             this.label4.Name = "label4";
-            this.label4.Size = new System.Drawing.Size(56, 13);
+            this.label4.Size = new System.Drawing.Size(60, 15);
             this.label4.TabIndex = 7;
             this.label4.Text = "Password:";
             // 
+            // label5
+            // 
+            this.label5.AutoSize = true;
+            this.label5.Location = new System.Drawing.Point(12, 190);
+            this.label5.Margin = new System.Windows.Forms.Padding(4, 0, 4, 0);
+            this.label5.Name = "label5";
+            this.label5.Size = new System.Drawing.Size(99, 15);
+            this.label5.TabIndex = 9;
+            this.label5.Text = "Connection Type:";
+            // 
+            // connectionType
+            // 
+            this.connectionType.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
+            this.connectionType.FormattingEnabled = true;
+            this.connectionType.Items.AddRange(new object[] {
+            "Websockets (Recommended)",
+            "Long HTTP JSON (Robust)"});
+            this.connectionType.Location = new System.Drawing.Point(14, 208);
+            this.connectionType.Name = "connectionType";
+            this.connectionType.Size = new System.Drawing.Size(318, 23);
+            this.connectionType.TabIndex = 10;
+            this.connectionType.TextChanged += new System.EventHandler(this.connectionType_TextChanged);
+            // 
             // SubscribeDialog
             // 
-            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+            this.AutoScaleDimensions = new System.Drawing.SizeF(7F, 15F);
             this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
             this.BackColor = System.Drawing.Color.White;
-            this.ClientSize = new System.Drawing.Size(297, 219);
+            this.ClientSize = new System.Drawing.Size(346, 295);
+            this.Controls.Add(this.connectionType);
+            this.Controls.Add(this.label5);
             this.Controls.Add(this.password);
             this.Controls.Add(this.label4);
             this.Controls.Add(this.username);
@@ -172,6 +208,7 @@ namespace ntfysh_client
             this.Controls.Add(this.label1);
             this.Controls.Add(this.panel1);
             this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
+            this.Margin = new System.Windows.Forms.Padding(4, 3, 4, 3);
             this.MaximizeBox = false;
             this.MinimizeBox = false;
             this.Name = "SubscribeDialog";
@@ -179,6 +216,7 @@ namespace ntfysh_client
             this.ShowInTaskbar = false;
             this.StartPosition = System.Windows.Forms.FormStartPosition.CenterParent;
             this.Text = "Subscribe to new topic";
+            this.Load += new System.EventHandler(this.SubscribeDialog_Load);
             this.panel1.ResumeLayout(false);
             this.ResumeLayout(false);
             this.PerformLayout();
@@ -199,5 +237,7 @@ namespace ntfysh_client
         private System.Windows.Forms.Label label3;
         private System.Windows.Forms.TextBox password;
         private System.Windows.Forms.Label label4;
+        private System.Windows.Forms.Label label5;
+        private System.Windows.Forms.ComboBox connectionType;
     }
 }

ntfysh_client/SubscribeDialog.cs

@@ -17,12 +17,107 @@ namespace ntfysh_client
 
         public string Unique => $"{topicId.Text}@{serverUrl.Text}";
 
+        public bool UseWebsockets
+        {
+            get
+            {
+                switch (connectionType.Text)
+                {
+                    case "Websockets (Recommended)":
+                        return true;
+
+                    case "Long HTTP JSON (Robust)":
+                        return false;
+
+                    default:
+                        throw new InvalidOperationException();
+                }
+            }
+        }
+
         public SubscribeDialog(ListBox notificationTopics)
         {
             _notificationTopics = notificationTopics;
             InitializeComponent();
         }
 
+        private void SubscribeDialog_Load(object sender, EventArgs e)
+        {
+            connectionType.SelectedIndex = 0;
+        }
+
+        private bool ReparseAddress()
+        {
+            //Separate schema and address
+            string[] parts = serverUrl.Text.Split("://", 2);
+
+            //Validate the basic formatting is correct
+            if (parts.Length != 2) return false;
+
+            //Take the schema aside for parsing
+            string schema = parts[0].ToLower();
+
+            //Ensure the schema is actually valid
+            switch (schema)
+            {
+                case "http":
+                case "https":
+                case "ws":
+                case "wss":
+                    break;
+
+                default:
+                    return false;
+            }
+
+            //Correct the schema based on connection type if required
+            if (UseWebsockets)
+            {
+                switch (schema)
+                {
+                    case "http":
+                        schema = "ws";
+                        break;
+
+                    case "https":
+                        schema = "wss";
+                        break;
+
+                    case "ws":
+                    case "wss":
+                        break;
+                }
+            }
+            else
+            {
+                switch (schema)
+                {
+                    case "ws":
+                        schema = "http";
+                        break;
+
+                    case "wss":
+                        schema = "https";
+                        break;
+
+                    case "http":
+                    case "https":
+                        break;
+                }
+            }
+
+            //Reconstruct the address
+            string finalAddress = schema + "://" + parts[1];
+
+            //Validate the address
+            if (!Uri.IsWellFormedUriString(finalAddress, UriKind.Absolute)) return false;
+
+            //Set the final address and OK it
+            serverUrl.Text = finalAddress;
+
+            return true;
+        }
+
         private void button1_Click(object sender, EventArgs e)
         {
             if (topicId.Text.Length < 1)
@@ -35,7 +130,7 @@ namespace ntfysh_client
 
             if (serverUrl.Text.Length < 1)
             {
-                MessageBox.Show("You must specify a server URL. The default is https://ntfy.sh", "Server URL not specified", MessageBoxButtons.OK, MessageBoxIcon.Error);
+                MessageBox.Show("You must specify a server URL. The default is wss://ntfy.sh", "Server URL not specified", MessageBoxButtons.OK, MessageBoxIcon.Error);
                 DialogResult = DialogResult.None;
                 serverUrl.Focus();
                 return;
@@ -65,6 +160,26 @@ namespace ntfysh_client
                 return;
             }
 
+            try
+            {
+                if (!ReparseAddress())
+                {
+                    MessageBox.Show($"The specified server URL is invalid. Accepted schemas are: http:// https:// ws:// wss://", "Invalid Server URL", MessageBoxButtons.OK, MessageBoxIcon.Error);
+                    DialogResult = DialogResult.None;
+                    connectionType.Focus();
+                    return;
+                }
+            }
+            catch (InvalidOperationException)
+            {
+                MessageBox.Show($"The selected Connection Type '{connectionType.Text}' is invalid.", "Invalid Connection Type", MessageBoxButtons.OK, MessageBoxIcon.Error);
+                DialogResult = DialogResult.None;
+                connectionType.Focus();
+                return;
+            }
+
+
+
             DialogResult = DialogResult.OK;
         }
 
@@ -108,5 +223,10 @@ namespace ntfysh_client
                 e.SuppressKeyPress = true;
             }
         }
+
+        private void connectionType_TextChanged(object sender, EventArgs e)
+        {
+            ReparseAddress();
+        }
     }
 }

ntfysh_client/SubscribeDialog.resx

@@ -1,64 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<root>
-<root>
-  <!-- 
-    Microsoft ResX Schema 
-    
-    Version 2.0
-    
-    The primary goals of this format is to allow a simple XML format 
-    that is mostly human readable. The generation and parsing of the 
-    various data types are done through the TypeConverter classes 
-    associated with the data types.
-    
-    Example:
-    
-    ... ado.net/XML headers & schema ...
-    <resheader name="resmimetype">text/microsoft-resx</resheader>
-    <resheader name="version">2.0</resheader>
-    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
-    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
-    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
-    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
-    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
-        <value>[base64 mime encoded serialized .NET Framework object]</value>
-    </data>
-    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
-        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
-        <comment>This is a comment</comment>
-    </data>
-                
-    There are any number of "resheader" rows that contain simple 
-    name/value pairs.
-    
-    Each data row contains a name, and value. The row also contains a 
-    type or mimetype. Type corresponds to a .NET class that support 
-    text/value conversion through the TypeConverter architecture. 
-    Classes that don't support this are serialized and stored with the 
-    mimetype set.
-    
-    The mimetype is used for serialized objects, and tells the 
-    ResXResourceReader how to depersist the object. This is currently not 
-    extensible. For a given mimetype the value must be set accordingly:
-    
-    Note - application/x-microsoft.net.object.binary.base64 is the format 
-    that the ResXResourceWriter will generate, however the reader can 
-    read any of the formats listed below.
-    
-    mimetype: application/x-microsoft.net.object.binary.base64
-    value   : The object must be serialized with 
-            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
-            : and then encoded with base64 encoding.
-    
-    mimetype: application/x-microsoft.net.object.soap.base64
-    value   : The object must be serialized with 
-            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
-            : and then encoded with base64 encoding.
-
-    mimetype: application/x-microsoft.net.object.bytearray.base64
-    value   : The object must be serialized into a byte array 
-            : using a System.ComponentModel.TypeConverter
-            : and then encoded with base64 encoding.
-    -->
   <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
     <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
     <xsd:element name="root" msdata:IsDataSet="true">