Disable network capture and hide behind constant

docs/opc-publisher/commandline.md

@@ -859,21 +859,11 @@ Diagnostic options
       --cap, --capturedevice, --CaptureDevice=VALUE
                              The capture device to use to capture network
                                traffic.
-                               Available devices on this system:
-                                   `Local Area Connection* 10`
-                                   `Local Area Connection* 9`
-                                   `Local Area Connection* 8`
-                                   `vEthernet (Default Switch)`
-                                   `Bluetooth Network Connection`
-                                   `Local Area Connection* 2`
-                                   `Local Area Connection* 1`
-                                   `Ethernet`
-                                   `Wi-Fi`
-                                   `\Device\NPF_Loopback`
-                               Default: `null` (disabled).
+                               Network capture is not supported on this system.
       --cpf, --capturefile, --CaptureFileName=VALUE
                              The file name to capture traffic to.
-                               A device must be selected using `--cd`.
+                               A device must be selected using `--cd` if
+                               capture capability is supported on this system.
                                Default: `opcua.pcap`.
 ```
 

src/Azure.IIoT.OpcUa.Publisher.Module/src/Runtime/CommandLine.cs

@@ -476,10 +476,10 @@ public CommandLine(string[] args, CommandLineLogger? logger = null)
                     "Explicitly enable or disable exporting prometheus metrics directly on the standard path.\nDefault: `disabled` if Otlp collector is configured, otherwise `enabled`.\n",
                     (bool? b) => this[Configuration.Otlp.EnableMetricsKey] = b?.ToString() ?? "True" },
                 { $"cap|capturedevice=|{OpcUaClientConfig.CaptureDeviceKey}=",
-                    $"The capture device to use to capture network traffic.\nAvailable devices on this system:\n    `{string.Join("`\n    `", OpcUaClientCapture.AvailableDevices)}`\nDefault: `null` (disabled).\n",
+                    $"The capture device to use to capture network traffic.\n{SupportsCapture(OpcUaClientCapture.AvailableDevices)}\n",
                     (string s) => this[OpcUaClientConfig.CaptureDeviceKey] = s },
                 { $"cpf|capturefile=|{OpcUaClientConfig.CaptureFileNameKey}=",
-                    $"The file name to capture traffic to.\nA device must be selected using `--cd`.\nDefault: `{OpcUaClientConfig.CaptureFileNameDefault}`.\n",
+                    $"The file name to capture traffic to.\nA device must be selected using `--cd` if capture capability is supported on this system.\nDefault: `{OpcUaClientConfig.CaptureFileNameDefault}`.\n",
                     (string s) => this[OpcUaClientConfig.CaptureFileNameKey] = s },
 
                 // testing purposes
@@ -617,6 +617,16 @@ void SetStoreType(string s, string storeTypeKey, string optionName)
                 throw new OptionException("Bad store type", optionName);
             }
         }
+
+        private static string SupportsCapture(IReadOnlyList<string> devices)
+        {
+            if (devices.Count == 0)
+            {
+                return "Network capture is not supported on this system.";
+            }
+            return $"Available devices on your system:\n    `{string.Join("`\n    `", devices)}`\nDefault: `null` (disabled).";
+        }
+
         private readonly CommandLineLogger _logger;
     }
 

src/Azure.IIoT.OpcUa.Publisher/src/Azure.IIoT.OpcUa.Publisher.csproj

@@ -4,14 +4,19 @@
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <Nullable>enable</Nullable>
   </PropertyGroup>
+  <PropertyGroup  Condition=" '$(SHARPPCAP)' != '' ">
+    <DefineConstants>SHARPPCAP</DefineConstants>
+  </PropertyGroup>
+  <ItemGroup Condition=" '$(SHARPPCAP)' != '' ">
+    <PackageReference Include="SharpPcap" Version="6.2.5" />
+  </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="8.0.0" />
     <PackageReference Include="Nito.AsyncEx" Version="5.1.2" />
     <PackageReference Include="Furly.Azure.IoT.Edge" Version="1.0.18" />
     <PackageReference Include="Irony" Version="1.2.0" />
     <PackageReference Include="OPCFoundation.NetStandard.Opc.Ua.Client.ComplexTypes" Version="1.4.372.106" />
     <PackageReference Include="OPCFoundation.NetStandard.Opc.Ua.Client" Version="1.4.372.106" />
-    <PackageReference Include="SharpPcap" Version="6.2.5" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\Azure.IIoT.OpcUa\src\Azure.IIoT.OpcUa.csproj" />

src/Azure.IIoT.OpcUa.Publisher/src/Stack/Services/OpcUaClientCapture.cs

@@ -8,8 +8,10 @@ namespace Azure.IIoT.OpcUa.Publisher.Stack.Services
     using Microsoft.Extensions.Logging;
     using Microsoft.Extensions.Options;
     using System;
+#if SHARPPCAP
     using SharpPcap;
     using SharpPcap.LibPcap;
+#endif
     using System.Collections.Generic;
     using System.Linq;
     using System.IO;
@@ -27,13 +29,15 @@ public static IReadOnlyList<string> AvailableDevices
         {
             get
             {
+#if SHARPPCAP
                 try
                 {
                     return LibPcapLiveDeviceList.Instance
                         .Select(d => d.Interface.FriendlyName ?? d.Name)
                         .ToArray();
                 }
                 catch
+#endif
                 {
                     return Array.Empty<string>();
                 }
@@ -62,6 +66,7 @@ public void Start()
                 return;
             }
 
+#if SHARPPCAP
             _logger.LogInformation("Using SharpPcap {Version}", Pcap.SharpPcapVersion);
             var device = FindDeviceByName(deviceName);
             if (device == null)
@@ -73,15 +78,21 @@ public void Start()
 
             _device?.Dispose();
             _device = new CaptureDevice(this, device, _options.Value.CaptureFileName);
+#else
+            _logger.LogWarning("SharpPcap is not included in this build.");
+#endif
         }
 
         /// <inheritdoc/>
         public void Dispose()
         {
+#if SHARPPCAP
             _device?.Dispose();
             _device = null;
+#endif
         }
 
+#if SHARPPCAP
         /// <summary>
         /// Find device by name
         /// </summary>
@@ -173,6 +184,7 @@ public void Dispose()
         }
 
         private CaptureDevice? _device;
+#endif
         private readonly IOptions<OpcUaClientOptions> _options;
         private readonly ILogger<OpcUaClientCapture> _logger;
     }