mirror of
https://github.com/OPCFoundation/UA-.NETStandard.git
synced 2026-10-18 22:55:08 +08:00
Marc Schier
917 lines
37 KiB
C#
917 lines
37 KiB
C#
/* ========================================================================
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* Copyright (c) 2005-2025 The OPC Foundation, Inc. All rights reserved.
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*
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* OPC Foundation MIT License 1.00
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*
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* Permission is hereby granted, free of charge, to any person
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* obtaining a copy of this software and associated documentation
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* files (the "Software"), to deal in the Software without
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* restriction, including without limitation the rights to use,
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* copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following
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* conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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* OTHER DEALINGS IN THE SOFTWARE.
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*
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* The complete license agreement can be found here:
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* http://opcfoundation.org/License/MIT/1.00/
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* ======================================================================*/
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using System;
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using System.Collections.Generic;
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using System.IO;
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using System.Runtime.CompilerServices;
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using System.Threading;
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using System.Threading.Tasks;
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using Microsoft.Extensions.Logging;
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namespace Opc.Ua.Client
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{
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/// <summary>
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/// Address space browsing functionality.
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/// </summary>
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public class Browser
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{
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/// <summary>
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/// Creates new instance of a browser and attaches it to a session.
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/// </summary>
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public Browser(
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ITelemetryContext telemetry,
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BrowserOptions? options = null)
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{
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m_telemetry = telemetry;
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m_logger = m_telemetry.CreateLogger<Browser>();
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State = options ?? new BrowserOptions();
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}
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/// <summary>
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/// Creates new instance of a browser and attaches it to a session.
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/// </summary>
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public Browser(
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ISessionClient session,
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BrowserOptions? options = null)
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{
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m_telemetry = session.MessageContext.Telemetry;
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m_logger = m_telemetry.CreateLogger<Browser>();
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State = options ?? new BrowserOptions();
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Session = session;
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}
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/// <summary>
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/// Creates an unattached instance of a browser.
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/// </summary>
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[Obsolete("Use constructor with ISessionClient or ITelemetryContext.")]
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public Browser(BrowserOptions? options = null)
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{
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m_logger = m_telemetry.CreateLogger<Browser>();
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State = options ?? new BrowserOptions();
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}
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/// <summary>
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/// Creates a copy of a browser.
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/// </summary>
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[Obsolete("Use the constructor that accepts BrowserOptions instead.")]
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public Browser(Browser template)
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{
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if (template == null)
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{
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throw new ArgumentNullException(nameof(template));
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}
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m_logger = template.m_logger;
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m_telemetry = template.m_telemetry;
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State = template.State;
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Session = template.Session;
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ContinueUntilDone = template.ContinueUntilDone;
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}
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/// <summary>
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/// Browwser state
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/// </summary>
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public BrowserOptions State { get; private set; }
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/// <summary>
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/// The session that the browse is attached to.
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/// </summary>
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public ISessionClient? Session
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{
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get;
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set
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{
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if (value is ISession session)
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{
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MaxNodesPerBrowse =
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session.OperationLimits.MaxNodesPerBrowse;
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MaxBrowseContinuationPoints =
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session.ServerCapabilities.MaxBrowseContinuationPoints;
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ContinuationPointPolicy =
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session.ContinuationPointPolicy;
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}
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field = value;
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}
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}
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/// <summary>
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/// The view to use for the browse operation.
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/// </summary>
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public RequestHeader? RequestHeader
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{
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get => State.RequestHeader;
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set => State = State with { RequestHeader = value };
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}
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/// <summary>
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/// The continuation point strategy to use
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/// </summary>
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public ContinuationPointPolicy ContinuationPointPolicy
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{
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get => State.ContinuationPointPolicy;
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set => State = State with { ContinuationPointPolicy = value };
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}
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/// <summary>
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/// Max nodes to browse in a single operation
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/// </summary>
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public uint MaxNodesPerBrowse
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{
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get => State.MaxNodesPerBrowse;
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set => State = State with { MaxNodesPerBrowse = value };
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}
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/// <summary>
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/// Max continuation point limit to use
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/// </summary>
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public ushort MaxBrowseContinuationPoints
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{
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get => State.MaxBrowseContinuationPoints;
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set => State = State with { MaxBrowseContinuationPoints = value };
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}
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/// <summary>
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/// The view to use for the browse operation.
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/// </summary>
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public ViewDescription? View
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{
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get => State.View;
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set => State = State with { View = value };
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}
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/// <summary>
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/// The maximum number of references to return in a single browse operation.
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/// </summary>
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public uint MaxReferencesReturned
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{
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get => State.MaxReferencesReturned;
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set => State = State with { MaxReferencesReturned = value };
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}
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/// <summary>
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/// The direction to browse.
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/// </summary>
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public BrowseDirection BrowseDirection
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{
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get => State.BrowseDirection;
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set => State = State with { BrowseDirection = value };
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}
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/// <summary>
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/// The reference type to follow.
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/// </summary>
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public NodeId ReferenceTypeId
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{
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get => State.ReferenceTypeId;
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set => State = State with { ReferenceTypeId = value };
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}
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/// <summary>
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/// Whether subtypes of the reference type should be included.
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/// </summary>
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public bool IncludeSubtypes
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{
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get => State.IncludeSubtypes;
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set => State = State with { IncludeSubtypes = value };
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}
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/// <summary>
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/// The classes of the target nodes.
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/// </summary>
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public uint NodeClassMask
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{
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get => Utils.ToUInt32(State.NodeClassMask);
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set => State = State with { NodeClassMask = Utils.ToInt32(value) };
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}
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/// <summary>
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/// The results to return.
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/// </summary>
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public uint ResultMask
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{
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get => State.ResultMask;
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set => State = State with { ResultMask = value };
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}
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/// <summary>
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/// Raised when a browse operation halted because of a continuation point.
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/// </summary>
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public event BrowserEventHandler MoreReferences
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{
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add => m_MoreReferences += value;
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remove => m_MoreReferences -= value;
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}
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/// <summary>
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/// Whether subsequent continuation points should be processed automatically.
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/// </summary>
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public bool ContinueUntilDone { get; set; }
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/// <summary>
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/// Browses the specified node.
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/// </summary>
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[Obsolete("Use BrowseAsync(NodeId) instead.")]
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public ArrayOf<ReferenceDescription> Browse(NodeId nodeId)
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{
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return BrowseAsync(nodeId).AsTask().GetAwaiter().GetResult();
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}
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/// <summary>
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/// Browses the specified node.
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/// </summary>
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/// <exception cref="ServiceResultException"></exception>
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public async ValueTask<ArrayOf<ReferenceDescription>> BrowseAsync(
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NodeId nodeId,
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CancellationToken ct = default)
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{
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BrowserOptions state = State;
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ISessionClient session = Session ??
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throw new ServiceResultException(
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StatusCodes.BadServerNotConnected,
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"Cannot browse if not connected to a server.");
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// construct request.
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var nodeToBrowse = new BrowseDescription
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{
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NodeId = nodeId,
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BrowseDirection = state.BrowseDirection,
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ReferenceTypeId = state.ReferenceTypeId,
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IncludeSubtypes = state.IncludeSubtypes,
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NodeClassMask = Utils.ToUInt32(state.NodeClassMask),
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ResultMask = state.ResultMask
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};
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ArrayOf<BrowseDescription> nodesToBrowse = [nodeToBrowse];
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// make the call to the server.
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BrowseResponse browseResponse = await session.BrowseAsync(
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state.RequestHeader,
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state.View,
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state.MaxReferencesReturned,
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nodesToBrowse,
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ct).ConfigureAwait(false);
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ArrayOf<BrowseResult> results = browseResponse.Results;
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ArrayOf<DiagnosticInfo> diagnosticInfos = browseResponse.DiagnosticInfos;
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ResponseHeader responseHeader = browseResponse.ResponseHeader;
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// ensure that the server returned valid results.
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ClientBase.ValidateResponse(results, nodesToBrowse);
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ClientBase.ValidateDiagnosticInfos(diagnosticInfos, nodesToBrowse);
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// check if valid.
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if (StatusCode.IsBad(results[0].StatusCode))
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{
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throw ServiceResultException.Create(
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results[0].StatusCode,
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0,
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diagnosticInfos,
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responseHeader.StringTable);
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}
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// fetch initial set of references.
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ByteString continuationPoint = results[0].ContinuationPoint;
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ArrayOf<ReferenceDescription> references = results[0].References;
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try
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{
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// process any continuation point.
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while (!continuationPoint.IsEmpty)
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{
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ArrayOf<ReferenceDescription> additionalReferences;
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if (!ContinueUntilDone && m_MoreReferences != null)
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{
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var args = new BrowserEventArgs(references);
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m_MoreReferences(this, args);
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// cancel browser and return the references fetched so far.
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if (args.Cancel)
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{
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session = Session;
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if (session != null)
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{
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(_, continuationPoint) = await BrowseNextAsync(
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session,
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continuationPoint,
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true,
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ct).ConfigureAwait(false);
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}
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return references;
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}
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ContinueUntilDone = args.ContinueUntilDone;
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}
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// See if the session was updated
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session = Session ??
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throw new ServiceResultException(
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StatusCodes.BadServerNotConnected,
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"Cannot browse if not connected to a server.");
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(additionalReferences, continuationPoint) = await BrowseNextAsync(
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session,
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continuationPoint,
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false,
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ct).ConfigureAwait(false);
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if (!additionalReferences.IsEmpty)
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{
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references = references.AddItems(additionalReferences);
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}
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else
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{
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m_logger.LogWarning(
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"Browser: Continuation point exists, but the browse results are null/empty.");
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break;
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}
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}
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}
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catch (OperationCanceledException) when (!continuationPoint.IsEmpty)
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{
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session = Session;
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if (session != null)
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{
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(_, _) = await BrowseNextAsync(
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session,
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continuationPoint,
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true,
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default).ConfigureAwait(false);
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}
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}
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// return the results.
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return references;
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}
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/// <summary>
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/// 1. if, during a Browse or BrowseNext, service call one of the status codes
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/// BadNoContinuationPoint or BadContinuationPointInvalid is returned,
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/// the node is browsed again.
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/// 2. tries to avoid the status code BadNoContinuationPoint by creating
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/// packages of size at most MaxNodesPerBrowse, taken from the Operationlimits
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/// retrieved from the server at client startup.
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/// 3. with the help of a new property of the session the new method calls
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/// Browse for at most
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/// min(MaxNodesPerBrowse, MaxBrowseContinuationPoints)
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/// nodes in one call, to further reduce the risk of the status code
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/// BadNoContinuationPoint
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/// 4. calls BrowseNext, if necessary, before working on a new package. This is
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/// the reason that the packages have to be created directly in this method
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/// and package creation cannot be delegated to the SessionClientBatched class.
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/// This call sequence avoids the cannibalization of continuation points from
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/// previously worked on packages, at least if no concurrent browse operation
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/// is started. (The server is supposed to manage the continuation point quota
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/// on session level.The reference server, which is used in the tests, does
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/// this correctly).
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/// 5. the maximum number of browse continuation points is retrieved from
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/// the server capabilities in a new method, which may also be viewed as
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/// a prototype for evaluation of all server capabilities (this is not an
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/// operation limit).
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/// </summary>
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/// <param name="nodesToBrowse">The nodes to browse</param>
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/// <param name="ct">Cancellation token to use</param>
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/// <returns></returns>
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/// <exception cref="ServiceResultException"></exception>
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public async ValueTask<ResultSet<ArrayOf<ReferenceDescription>>> BrowseAsync(
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ArrayOf<NodeId> nodesToBrowse,
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CancellationToken ct = default)
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{
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BrowserOptions state = State;
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ISessionClient session = Session ??
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throw new ServiceResultException(
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StatusCodes.BadServerNotConnected,
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"Cannot browse if not connected to a server.");
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int count = nodesToBrowse.Count;
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var result = new List<List<ReferenceDescription>>(count);
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var errors = new List<ServiceResult>(count);
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// first attempt for implementation: create the references for the output in advance.
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// optimize later, when everything works fine.
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for (int i = 0; i < nodesToBrowse.Count; i++)
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{
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result.Add([]);
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errors.Add(new ServiceResult(StatusCodes.Good));
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}
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// in the first pass, we browse all nodes from the input.
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// Some nodes may need to be browsed again, these are then fed into the next pass.
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var nodesToBrowseForPass = new List<NodeId>(count);
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nodesToBrowseForPass.AddRange(nodesToBrowse);
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var resultForPass = new List<List<ReferenceDescription>>(count);
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resultForPass.AddRange(result);
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var errorsForPass = new List<ServiceResult>(count);
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errorsForPass.AddRange(errors);
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int passCount = 0;
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do
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{
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int badNoCPErrorsPerPass = 0;
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int badCPInvalidErrorsPerPass = 0;
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int otherErrorsPerPass = 0;
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uint maxNodesPerBrowse = MaxNodesPerBrowse;
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if (ContinuationPointPolicy == ContinuationPointPolicy.Balanced &&
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MaxBrowseContinuationPoints > 0)
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{
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maxNodesPerBrowse =
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MaxBrowseContinuationPoints < maxNodesPerBrowse
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? MaxBrowseContinuationPoints
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: maxNodesPerBrowse;
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}
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// split input into batches
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int batchOffset = 0;
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var nodesToBrowseForNextPass = new List<NodeId>();
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var referenceDescriptionsForNextPass
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= new List<List<ReferenceDescription>>();
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var errorsForNextPass = new List<ServiceResult>();
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// loop over the batches
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foreach (ArrayOf<NodeId> nodesToBrowseBatch in
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nodesToBrowseForPass.ToArrayOf().Batch((int)maxNodesPerBrowse))
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{
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int nodesToBrowseBatchCount = nodesToBrowseBatch.Count;
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ResultSet<ArrayOf<ReferenceDescription>> results = await BrowseAsync(
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session,
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state.RequestHeader,
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state.View,
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nodesToBrowseBatch,
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state.MaxReferencesReturned,
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state.BrowseDirection,
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state.ReferenceTypeId,
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state.IncludeSubtypes,
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state.NodeClassMask,
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ct)
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.ConfigureAwait(false);
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int resultOffset = batchOffset;
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for (int ii = 0; ii < nodesToBrowseBatchCount; ii++)
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{
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StatusCode statusCode = results.Errors[ii].StatusCode;
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if (StatusCode.IsBad(statusCode))
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{
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bool addToNextPass = false;
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if (statusCode == StatusCodes.BadNoContinuationPoints)
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{
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addToNextPass = true;
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badNoCPErrorsPerPass++;
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}
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else if (statusCode == StatusCodes.BadContinuationPointInvalid)
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{
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addToNextPass = true;
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badCPInvalidErrorsPerPass++;
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}
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else
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{
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otherErrorsPerPass++;
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}
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if (addToNextPass)
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{
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nodesToBrowseForNextPass.Add(
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nodesToBrowseForPass[resultOffset]);
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referenceDescriptionsForNextPass.Add(
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resultForPass[resultOffset]);
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errorsForNextPass.Add(errorsForPass[resultOffset]);
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}
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}
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resultForPass[resultOffset].Clear();
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resultForPass[resultOffset].AddRange(results.Results[ii]);
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errorsForPass[resultOffset] = results.Errors[ii];
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errors[resultOffset] = results.Errors[ii];
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resultOffset++;
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}
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batchOffset += nodesToBrowseBatchCount;
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}
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resultForPass = referenceDescriptionsForNextPass;
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errorsForPass = errorsForNextPass;
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nodesToBrowseForPass = nodesToBrowseForNextPass;
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if (badCPInvalidErrorsPerPass > 0)
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{
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m_logger.LogDebug(
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"ManagedBrowse: in pass {Pass}, {Count} error(s) occured with a status code {StatusCode}.",
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passCount,
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badCPInvalidErrorsPerPass,
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nameof(StatusCodes.BadContinuationPointInvalid));
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}
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if (badNoCPErrorsPerPass > 0)
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{
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m_logger.LogDebug(
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"ManagedBrowse: in pass {Pass}, {Count} error(s) occured with a status code {StatusCode}.",
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passCount,
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badNoCPErrorsPerPass,
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nameof(StatusCodes.BadNoContinuationPoints));
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}
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if (otherErrorsPerPass > 0)
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{
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m_logger.LogDebug(
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"ManagedBrowse: in pass {Pass}, {Count} error(s) occured with a status code {StatusCode}.",
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passCount,
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otherErrorsPerPass,
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$"different from {nameof(StatusCodes.BadNoContinuationPoints)} or {nameof(StatusCodes.BadContinuationPointInvalid)}");
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}
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if (otherErrorsPerPass == 0 &&
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badCPInvalidErrorsPerPass == 0 &&
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badNoCPErrorsPerPass == 0)
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{
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m_logger.LogTrace("ManagedBrowse completed with no errors.");
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}
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passCount++;
|
|
} while (nodesToBrowseForPass.Count > 0);
|
|
return ResultSet.From(result.ConvertAll(l => (ArrayOf<ReferenceDescription>)l), errors);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Browse the server address space returning results as an async stream.
|
|
/// Automatically handles continuation points and releases them on
|
|
/// disposal/cancellation. Uses the supplied
|
|
/// <paramref name="nodesToBrowse"/> verbatim — the caller controls
|
|
/// the browse description (NodeId, BrowseDirection, ReferenceTypeId,
|
|
/// IncludeSubtypes, NodeClassMask, ResultMask).
|
|
/// </summary>
|
|
/// <param name="requestHeader">The request header.</param>
|
|
/// <param name="view">The view to browse.</param>
|
|
/// <param name="nodesToBrowse">The set of browse operations to perform.</param>
|
|
/// <param name="ct">The cancellation token.</param>
|
|
/// <returns>An async stream of browse results.</returns>
|
|
/// <exception cref="ServiceResultException">Thrown when the browser
|
|
/// is not attached to a session.</exception>
|
|
public async IAsyncEnumerable<BrowseResult> BrowseStreamAsync(
|
|
RequestHeader? requestHeader,
|
|
ViewDescription? view,
|
|
ArrayOf<BrowseDescription> nodesToBrowse,
|
|
[EnumeratorCancellation] CancellationToken ct = default)
|
|
{
|
|
ISessionClient session = Session ??
|
|
throw new ServiceResultException(
|
|
StatusCodes.BadServerNotConnected,
|
|
"Cannot browse if not connected to a server.");
|
|
|
|
BrowseResponse first = await session.BrowseAsync(
|
|
requestHeader, view, 0, nodesToBrowse, ct).ConfigureAwait(false);
|
|
ClientBase.ValidateResponse(first.Results, nodesToBrowse);
|
|
ClientBase.ValidateDiagnosticInfos(first.DiagnosticInfos, nodesToBrowse);
|
|
|
|
var continuationPoints = new List<ByteString>();
|
|
for (int i = 0; i < first.Results.Count; i++)
|
|
{
|
|
BrowseResult result = first.Results[i];
|
|
if (StatusCode.IsGood(result.StatusCode) &&
|
|
!result.ContinuationPoint.IsNull &&
|
|
result.ContinuationPoint.Length != 0)
|
|
{
|
|
if (result.References.Count > 0)
|
|
{
|
|
continuationPoints.Add(result.ContinuationPoint);
|
|
}
|
|
else
|
|
{
|
|
m_logger.LogWarning(
|
|
"Browser: Server returned empty references but a " +
|
|
"continuation point. Stopping to prevent denial of service.");
|
|
yield return new BrowseResult
|
|
{
|
|
StatusCode = StatusCodes.BadNoData
|
|
};
|
|
continue;
|
|
}
|
|
}
|
|
yield return result;
|
|
}
|
|
|
|
try
|
|
{
|
|
while (continuationPoints.Count > 0)
|
|
{
|
|
BrowseNextResponse next = await session.BrowseNextAsync(
|
|
requestHeader, false,
|
|
continuationPoints.ToArrayOf(), ct).ConfigureAwait(false);
|
|
ClientBase.ValidateResponse(
|
|
next.Results, continuationPoints.ToArrayOf());
|
|
ClientBase.ValidateDiagnosticInfos(
|
|
next.DiagnosticInfos, continuationPoints.ToArrayOf());
|
|
|
|
continuationPoints = [];
|
|
for (int i = 0; i < next.Results.Count; i++)
|
|
{
|
|
BrowseResult result = next.Results[i];
|
|
if (StatusCode.IsGood(result.StatusCode) &&
|
|
!result.ContinuationPoint.IsNull &&
|
|
result.ContinuationPoint.Length != 0)
|
|
{
|
|
if (result.References.Count > 0)
|
|
{
|
|
continuationPoints.Add(result.ContinuationPoint);
|
|
}
|
|
else
|
|
{
|
|
m_logger.LogWarning(
|
|
"Browser: Server returned empty references " +
|
|
"but a continuation point. Stopping to prevent " +
|
|
"denial of service.");
|
|
yield return new BrowseResult
|
|
{
|
|
StatusCode = StatusCodes.BadNoData
|
|
};
|
|
continue;
|
|
}
|
|
}
|
|
yield return result;
|
|
}
|
|
}
|
|
}
|
|
finally
|
|
{
|
|
if (continuationPoints.Count > 0)
|
|
{
|
|
try
|
|
{
|
|
await session.BrowseNextAsync(
|
|
requestHeader, true,
|
|
continuationPoints.ToArrayOf(),
|
|
default).ConfigureAwait(false);
|
|
}
|
|
catch (Exception ex)
|
|
{
|
|
m_logger.LogError(ex,
|
|
"Browser: Failed to release continuation points.");
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Call the browse service asynchronously and call browse next,
|
|
/// if applicable, immediately afterwards. Observe proper treatment
|
|
/// of specific service results, specifically
|
|
/// BadNoContinuationPoint and BadContinuationPointInvalid
|
|
/// </summary>
|
|
private static async ValueTask<ResultSet<ArrayOf<ReferenceDescription>>> BrowseAsync(
|
|
ISessionClient session,
|
|
RequestHeader? requestHeader,
|
|
ViewDescription? view,
|
|
ArrayOf<NodeId> nodeIds,
|
|
uint maxResultsToReturn,
|
|
BrowseDirection browseDirection,
|
|
NodeId referenceTypeId,
|
|
bool includeSubtypes,
|
|
int nodeClassMask,
|
|
CancellationToken ct = default)
|
|
{
|
|
requestHeader?.RequestHandle = 0;
|
|
(
|
|
_,
|
|
ArrayOf<ByteString> continuationPoints,
|
|
ArrayOf<ArrayOf<ReferenceDescription>> referenceDescriptions,
|
|
ArrayOf<ServiceResult> errors
|
|
) = await session.BrowseAsync(
|
|
requestHeader,
|
|
view,
|
|
nodeIds,
|
|
maxResultsToReturn,
|
|
browseDirection,
|
|
referenceTypeId,
|
|
includeSubtypes,
|
|
(uint)nodeClassMask,
|
|
ct)
|
|
.ConfigureAwait(false);
|
|
|
|
var result = new List<List<ReferenceDescription>>(nodeIds.Count);
|
|
result.AddRange(referenceDescriptions.ConvertAll(l => l.ToList()).ToList());
|
|
|
|
// process any continuation point.
|
|
List<List<ReferenceDescription>> previousResults = [.. result];
|
|
var errorAnchors = new List<ReferenceWrapper<ServiceResult>>();
|
|
var previousErrors = new List<ReferenceWrapper<ServiceResult>>();
|
|
foreach (ServiceResult error in errors)
|
|
{
|
|
previousErrors.Add(new ReferenceWrapper<ServiceResult> { Reference = error });
|
|
errorAnchors.Add(previousErrors[^1]);
|
|
}
|
|
|
|
var nextContinuationPoints = new List<ByteString>();
|
|
var nextResults = new List<List<ReferenceDescription>>();
|
|
var nextErrors = new List<ReferenceWrapper<ServiceResult>>();
|
|
|
|
for (int ii = 0; ii < nodeIds.Count; ii++)
|
|
{
|
|
if (!continuationPoints[ii].IsEmpty &&
|
|
!StatusCode.IsBad(previousErrors[ii].Reference.StatusCode))
|
|
{
|
|
nextContinuationPoints.Add(continuationPoints[ii]);
|
|
nextResults.Add(previousResults[ii]);
|
|
nextErrors.Add(previousErrors[ii]);
|
|
}
|
|
}
|
|
while (nextContinuationPoints.Count > 0)
|
|
{
|
|
requestHeader?.RequestHandle = 0;
|
|
(
|
|
_,
|
|
ArrayOf<ByteString> revisedContinuationPoints,
|
|
ArrayOf<ArrayOf<ReferenceDescription>> browseNextResults,
|
|
ArrayOf<ServiceResult> browseNextErrors
|
|
) = await session.BrowseNextAsync(
|
|
requestHeader,
|
|
nextContinuationPoints,
|
|
false,
|
|
ct).ConfigureAwait(false);
|
|
|
|
for (int ii = 0; ii < browseNextResults.Count; ii++)
|
|
{
|
|
nextResults[ii].AddRange(browseNextResults[ii]);
|
|
nextErrors[ii].Reference = browseNextErrors[ii];
|
|
}
|
|
|
|
previousResults = nextResults;
|
|
previousErrors = nextErrors;
|
|
|
|
nextResults = [];
|
|
nextErrors = [];
|
|
nextContinuationPoints = [];
|
|
|
|
for (int ii = 0; ii < revisedContinuationPoints.Count; ii++)
|
|
{
|
|
if (!revisedContinuationPoints[ii].IsEmpty &&
|
|
!StatusCode.IsBad(browseNextErrors[ii].StatusCode))
|
|
{
|
|
nextContinuationPoints.Add(revisedContinuationPoints[ii]);
|
|
nextResults.Add(previousResults[ii]);
|
|
nextErrors.Add(previousErrors[ii]);
|
|
}
|
|
}
|
|
}
|
|
var finalErrors = new List<ServiceResult>(errorAnchors.Count);
|
|
foreach (ReferenceWrapper<ServiceResult> errorReference in errorAnchors)
|
|
{
|
|
finalErrors.Add(errorReference.Reference);
|
|
}
|
|
|
|
return ResultSet.From(result.ConvertAll(l => (ArrayOf<ReferenceDescription>)l), finalErrors);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Fetches the next batch of references.
|
|
/// </summary>
|
|
/// <param name="session"></param>
|
|
/// <param name="continuationPoint">The continuation point.</param>
|
|
/// <param name="cancel">if set to <c>true</c> the browse operation is cancelled.</param>
|
|
/// <param name="ct">The cancellation token.</param>
|
|
/// <returns>The next batch of references</returns>
|
|
/// <exception cref="ServiceResultException"></exception>
|
|
private static async ValueTask<(ArrayOf<ReferenceDescription>, ByteString)> BrowseNextAsync(
|
|
ISessionClient session,
|
|
ByteString continuationPoint,
|
|
bool cancel,
|
|
CancellationToken ct = default)
|
|
{
|
|
ArrayOf<ByteString> continuationPoints = [continuationPoint];
|
|
|
|
// make the call to the server.
|
|
BrowseNextResponse browseResponse = await session.BrowseNextAsync(
|
|
null,
|
|
cancel,
|
|
continuationPoints,
|
|
ct)
|
|
.ConfigureAwait(false);
|
|
|
|
ArrayOf<BrowseResult> results = browseResponse.Results;
|
|
ArrayOf<DiagnosticInfo> diagnosticInfos = browseResponse.DiagnosticInfos;
|
|
ResponseHeader responseHeader = browseResponse.ResponseHeader;
|
|
|
|
// ensure that the server returned valid results.
|
|
ClientBase.ValidateResponse(results, continuationPoints);
|
|
ClientBase.ValidateDiagnosticInfos(diagnosticInfos, continuationPoints);
|
|
|
|
// check if valid.
|
|
if (StatusCode.IsBad(results[0].StatusCode))
|
|
{
|
|
throw ServiceResultException.Create(
|
|
results[0].StatusCode,
|
|
0,
|
|
diagnosticInfos,
|
|
responseHeader.StringTable);
|
|
}
|
|
|
|
// return references and continuation point if provided.
|
|
return (results[0].References, results[0].ContinuationPoint);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Creates the browser from a persisted stream
|
|
/// </summary>
|
|
public static Browser? Load(Stream stream, ITelemetryContext telemetry)
|
|
{
|
|
var context = ServiceMessageContext.Create(telemetry);
|
|
using var decoder = new BinaryDecoder(stream, context, true);
|
|
ArrayOf<string?> nsUris = decoder.ReadStringArray(null);
|
|
ArrayOf<string?> serverUris = decoder.ReadStringArray(null);
|
|
// Namespace and server URI tables on the wire are encoded as nullable string
|
|
// arrays, but the runtime contract requires non-null entries; the bangs reflect
|
|
// that the decoder yields no null elements for these fields.
|
|
context.NamespaceUris = new NamespaceTable(nsUris.Memory.ToArray()!);
|
|
context.ServerUris = new StringTable(serverUris.Memory.ToArray()!);
|
|
var options = new BrowserOptions();
|
|
options.Decode(decoder);
|
|
return new Browser(telemetry, options);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Saves the state to the stream
|
|
/// </summary>
|
|
public void Save(Stream stream)
|
|
{
|
|
IServiceMessageContext context = AmbientMessageContext.CurrentContext
|
|
?? ServiceMessageContext.Create(m_telemetry);
|
|
using var encoder = new BinaryEncoder(stream, context, true);
|
|
encoder.WriteStringArray(
|
|
null, context.NamespaceUris.ToArrayOf());
|
|
encoder.WriteStringArray(
|
|
null, context.ServerUris.ToArrayOf());
|
|
State.Encode(encoder);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Used to pass on references to the Service results in the loop in ManagedBrowseAsync.
|
|
/// </summary>
|
|
/// <typeparam name="T"></typeparam>
|
|
private class ReferenceWrapper<T>
|
|
{
|
|
public required T Reference { get; set; }
|
|
}
|
|
|
|
private readonly ILogger m_logger;
|
|
private readonly ITelemetryContext? m_telemetry;
|
|
|
|
private event BrowserEventHandler? m_MoreReferences;
|
|
}
|
|
|
|
/// <summary>
|
|
/// The event arguments provided a browse operation returns a continuation point.
|
|
/// </summary>
|
|
public class BrowserEventArgs : EventArgs
|
|
{
|
|
/// <summary>
|
|
/// Creates a new instance.
|
|
/// </summary>
|
|
internal BrowserEventArgs(ArrayOf<ReferenceDescription> references)
|
|
{
|
|
References = references;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Whether the browse operation should be cancelled.
|
|
/// </summary>
|
|
public bool Cancel { get; set; }
|
|
|
|
/// <summary>
|
|
/// Whether subsequent continuation points should be processed automatically.
|
|
/// </summary>
|
|
public bool ContinueUntilDone { get; set; }
|
|
|
|
/// <summary>
|
|
/// The references that have been fetched so far.
|
|
/// </summary>
|
|
public ArrayOf<ReferenceDescription> References { get; }
|
|
}
|
|
|
|
/// <summary>
|
|
/// A delegate used to received browser events.
|
|
/// </summary>
|
|
public delegate void BrowserEventHandler(Browser sender, BrowserEventArgs e);
|
|
}
|