Samples Reappend

Libraries/h-opc/Common/ClientExtensions.cs

@@ -0,0 +1,34 @@
+using System;
+
+namespace Hylasoft.Opc.Common
+{
+  /// <summary>
+  /// Useful extension methods for OPC Clients
+  /// </summary>
+  public static class ClientExtensions
+  {
+    /// <summary>
+    /// Reads a tag from the OPC. If for whatever reason the read fails (Tag doesn't exist, server not available) returns a default value
+    /// </summary>
+    /// <param name="client">the opc client to use for the read</param>
+    /// <param name="tag">The fully qualified identifier of the tag</param>
+    /// <param name="defaultValue">the default value to read if the read fails</param>
+    /// <returns></returns>
+    public static ReadEvent<T> ReadOrdefault<T>(this IClient<Node> client, string tag, T defaultValue = default(T))
+    {
+      try
+      {
+        return client.Read<T>(tag);
+      }
+      catch (OpcException)
+      {
+        var readEvent = new ReadEvent<T>();
+        readEvent.Quality = Quality.Good;
+        readEvent.Value = defaultValue;
+        readEvent.SourceTimestamp = DateTime.Now;
+        readEvent.ServerTimestamp = DateTime.Now;
+        return readEvent;
+      }
+    }
+  }
+}

Libraries/h-opc/Common/IClient.cs

@@ -0,0 +1,103 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace Hylasoft.Opc.Common
+{
+  /// <summary>
+  /// Client interface to perform basic Opc tasks, like discovery, monitoring, reading/writing tags,
+  /// </summary>
+  public interface IClient<out TNode> : IDisposable
+    where TNode : Node
+  {
+    /// <summary>
+    /// Connect the client to the OPC Server
+    /// </summary>
+    Task Connect();
+
+    /// <summary>
+    /// Gets the current status of the OPC Client
+    /// </summary>
+    OpcStatus Status { get; }
+
+    /// <summary>
+    /// Gets the datatype of an OPC tag
+    /// </summary>
+    /// <param name="tag">Tag to get datatype of</param>
+    /// <returns>System Type</returns>
+    System.Type GetDataType(string tag);
+
+    /// <summary>
+    /// Read a tag
+    /// </summary>
+    /// <typeparam name="T">The type of tag to read</typeparam>
+    /// <param name="tag">The fully-qualified identifier of the tag. You can specify a subfolder by using a comma delimited name.
+    /// E.g: the tag `foo.bar` reads the tag `bar` on the folder `foo`</param>
+    /// <returns>The value retrieved from the OPC</returns>
+    ReadEvent<T> Read<T>(string tag);
+
+    /// <summary>
+    /// Write a value on the specified opc tag
+    /// </summary>
+    /// <typeparam name="T">The type of tag to write on</typeparam>
+    /// <param name="tag">The fully-qualified identifier of the tag. You can specify a subfolder by using a comma delimited name.
+    /// E.g: the tag `foo.bar` writes on the tag `bar` on the folder `foo`</param>
+    /// <param name="item"></param>
+    void Write<T>(string tag, T item);
+
+    /// <summary>
+    /// Monitor the specified tag for changes
+    /// </summary>
+    /// <typeparam name="T">the type of tag to monitor</typeparam>
+    /// <param name="tag">The fully-qualified identifier of the tag. You can specify a subfolder by using a comma delimited name.
+    /// E.g: the tag `foo.bar` monitors the tag `bar` on the folder `foo`</param>
+    /// <param name="callback">the callback to execute when the value is changed.
+    /// The first parameter is the new value of the node, the second is an `unsubscribe` function to unsubscribe the callback</param>
+    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures", Justification = "This is an async method.")]
+    void Monitor<T>(string tag, Action<ReadEvent<T>, Action> callback);
+
+    /// <summary>
+    /// Finds a node on the Opc Server
+    /// </summary>
+    /// <param name="tag">The fully-qualified identifier of the tag. You can specify a subfolder by using a comma delimited name.
+    /// E.g: the tag `foo.bar` finds the tag `bar` on the folder `foo`</param>
+    /// <returns>If there is a tag, it returns it, otherwise it throws an </returns>
+    TNode FindNode(string tag);
+
+    /// <summary>
+    /// Gets the root node of the server
+    /// </summary>
+    TNode RootNode { get; }
+
+    /// <summary>
+    /// Explore a folder on the Opc Server
+    /// </summary>
+    /// <param name="tag">The fully-qualified identifier of the tag. You can specify a subfolder by using a comma delimited name.
+    /// E.g: the tag `foo.bar` finds the sub nodes of `bar` on the folder `foo`</param>
+    /// <returns>The list of sub-nodes</returns>
+    IEnumerable<TNode> ExploreFolder(string tag);
+
+    /// <summary>
+    /// Read a tag asynchronusly
+    /// </summary>
+    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures", Justification = "This is an async method.")]
+    Task<ReadEvent<T>> ReadAsync<T>(string tag);
+
+    /// <summary>
+    /// Write a value on the specified opc tag asynchronously
+    /// </summary>
+    Task WriteAsync<T>(string tag, T item);
+
+    /// <summary>
+    /// Finds a node on the Opc Server asynchronously
+    /// </summary>
+    Task<Node> FindNodeAsync(string tag);
+
+    /// <summary>
+    /// Explore a folder on the Opc Server asynchronously
+    /// </summary>
+    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures",
+      Justification = "Task")]
+    Task<IEnumerable<Node>> ExploreFolderAsync(string tag);
+  }
+}

Libraries/h-opc/Common/Node.cs

@@ -0,0 +1,48 @@
+using System.Collections.Generic;
+
+namespace Hylasoft.Opc.Common
+{
+  /// <summary>
+  /// Base class representing a node on the OPC server
+  /// </summary>
+  public abstract class Node
+  {
+    /// <summary>
+    /// Gets the displayed name of the node
+    /// </summary>
+    public string Name { get; protected set; }
+
+    /// <summary>
+    /// Gets the dot-separated fully qualified tag of the node
+    /// </summary>
+    public string Tag { get; protected set; }
+
+    /// <summary>
+    /// Gets the parent node. If the node is root, returns null
+    /// </summary>
+    public Node Parent { get; private set; }
+
+    /// <summary>
+    /// Creates a new node
+    /// </summary>
+    /// <param name="name">the name of the node</param>
+    /// <param name="parent">The parent node</param>
+    protected Node(string name, Node parent = null)
+    {
+      Name = name;
+      Parent = parent;
+      if (parent != null && !string.IsNullOrEmpty(parent.Tag))
+        Tag = parent.Tag + '.' + name;
+      else
+        Tag = name;
+    }
+
+    /// <summary>
+    /// Overrides ToString()
+    /// </summary>
+    public override string ToString()
+    {
+      return Tag;
+    }
+  }
+}

Libraries/h-opc/Common/OpcException.cs

@@ -0,0 +1,70 @@
+using Opc.Ua;
+using System;
+using System.Runtime.Serialization;
+
+namespace Hylasoft.Opc.Common
+{
+  /// <summary>
+  /// Identifies an exception occurred during OPC Communication
+  /// </summary>
+  [Serializable]
+  public class OpcException : Exception
+  {
+    /// <summary>
+    /// Initialize a new instance of the OpcException class
+    /// </summary>
+    public OpcException()
+    {
+    }
+
+    /// <summary>
+    /// Initialize a new instance of the OpcException class
+    /// </summary>
+    public OpcException(string message)
+      : base(message)
+    {
+    }
+
+    /// <summary>
+    /// Returns an (optional) associated OPC UA StatusCode for the exception.
+    /// </summary>
+    public StatusCode? Status { get; private set; }
+
+    /// <summary>
+    /// Initialize a new instance of the OpcException class
+    /// </summary>
+    public OpcException(string message, StatusCode status)
+      : base(message)
+    {
+      Status = status;
+    }
+
+    /// <summary>
+    /// Initialize a new instance of the OpcException class
+    /// </summary>
+    public OpcException(string message, Exception inner)
+      : base(message, inner)
+    {
+    }
+
+    /// <summary>
+    /// Initialize a new instance of the OpcException class
+    /// </summary>
+    protected OpcException(SerializationInfo info, StreamingContext context)
+      : base(info, context)
+    {
+    }
+
+    /// <summary>
+    /// Sets the System.Runtime.Serialization.SerializationInfo with information about the exception.
+    /// </summary>
+    /// <param name="info">The System.Runtime.Serialization.SerializationInfo that holds the serialized object data about the exception being thrown.</param>
+    /// <param name="context">The System.Runtime.Serialization.StreamingContext that contains contextual information about the source or destination.</param>
+    public override void GetObjectData(SerializationInfo info, StreamingContext context)
+    {
+      base.GetObjectData(info, context);
+    }
+
+  }
+
+}

Libraries/h-opc/Common/OpcStatus.cs

@@ -0,0 +1,18 @@
+namespace Hylasoft.Opc.Common
+{
+  /// <summary>
+  /// Identifies the status of an OPC connector
+  /// </summary>
+  public enum OpcStatus
+  {
+    /// <summary>
+    /// The client is not connected
+    /// </summary>
+    NotConnected,
+
+    /// <summary>
+    /// The client is connected
+    /// </summary>
+    Connected
+  }
+}

Libraries/h-opc/Common/Quality.cs

@@ -0,0 +1,28 @@
+using System.ComponentModel;
+
+namespace Hylasoft.Opc.Common
+{
+  /// <summary>
+  /// Represents the quality of the value captured
+  /// </summary>
+  public enum Quality
+  {
+    /// <summary>
+    /// Quality: Unknown, the value of the quality could not be inferred by the library
+    /// </summary>
+    [Description("Unknown")]
+    Unknown,
+
+    /// <summary>
+    /// Quality: Good
+    /// </summary>
+    [Description("Good")]
+    Good,
+
+    /// <summary>
+    /// Quality: Bad
+    /// </summary>
+    [Description("Bad")]
+    Bad
+  }
+}

Libraries/h-opc/Common/ReadEvent.cs

@@ -0,0 +1,37 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Hylasoft.Opc.Common
+{
+  /// <summary>
+  /// Base class representing a monitor event on the OPC server
+  /// </summary>
+  /// <typeparam name="T"></typeparam>
+  public class ReadEvent<T>
+  {
+    /// <summary>
+    /// Gets the value that was read from the server
+    /// </summary>
+    public T Value { get; set; }
+
+    /// <summary>
+    /// Gets the quality of the signal from the server
+    /// </summary>
+    [DefaultValue(Common.Quality.Unknown)]
+    public Quality Quality { get; set; }
+
+    /// <summary>
+    /// Gets the source timestamp on when the event ocurred
+    /// </summary>
+    public DateTime SourceTimestamp { get; set; }
+
+    /// <summary>
+    /// Gets the server timestamp on when the event ocurred
+    /// </summary>
+    public DateTime ServerTimestamp { get; set; }
+  }
+}