Add guard rail to ensure we don't try to install on < IIS 10

DataDog · Feb 12, 2025 · d77915f · d77915f
1 parent 4bd714a
commit d77915f
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diff --git a/tracer/src/Datadog.FleetInstaller/Commands/CommandBase.cs b/tracer/src/Datadog.FleetInstaller/Commands/CommandBase.cs
@@ -35,6 +35,18 @@ protected bool IsValidEnvironment(CommandResult commandResult)
             return false;
         }
 
+        if (!RegistryHelper.TryGetIisVersion(Log.Instance, out var version))
+        {
+            commandResult.ErrorMessage = "This installer requires IIS 10.0 or later. Could not determine the IIS version; is the IIS feature enabled?";
+            return false;
+        }
+
+        if (version.Major < 10)
+        {
+            commandResult.ErrorMessage = $"This installer requires IIS 10.0 or later. Detected IIS version {version.Major}.{version.Minor}";
+            return false;
+        }
+
         return true;
     }
 }
diff --git a/tracer/src/Datadog.FleetInstaller/Datadog.FleetInstaller.csproj b/tracer/src/Datadog.FleetInstaller/Datadog.FleetInstaller.csproj
@@ -16,4 +16,9 @@
     <PackageReference Include="System.CommandLine" Version="2.0.0-beta4.22272.1" />
   </ItemGroup>
 
+  <ItemGroup>
+    <Compile Include="..\Datadog.Trace\Util\System.Diagnostics.CodeAnalysis.Attributes.cs" Link="Util\%(Filename)%(Extension)" />
+    <Compile Include="..\Datadog.Trace\Util\System.Runtime.CompilerServices.Attributes.cs" Link="Util\%(Filename)%(Extension)" />
+  </ItemGroup>
+
 </Project>
diff --git a/tracer/src/Datadog.FleetInstaller/RegistryHelper.cs b/tracer/src/Datadog.FleetInstaller/RegistryHelper.cs
@@ -4,6 +4,7 @@
 // </copyright>
 
 using System;
+using System.Diagnostics.CodeAnalysis;
 using Microsoft.Win32;
 
 namespace Datadog.FleetInstaller;
@@ -61,4 +62,34 @@ public static bool RemoveCrashTrackingKey(ILogger log, TracerValues values, stri
             return false;
         }
     }
+
+    public static bool TryGetIisVersion(ILogger log, [NotNullWhen(true)] out Version? version)
+    {
+        const string registryKeyName = @"Software\Microsoft\InetStp";
+
+        log.WriteInfo($"Reading IIS information from registry key: '{registryKeyName}'");
+
+        try
+        {
+            var key = Registry.LocalMachine.OpenSubKey(registryKeyName);
+            if (key is null)
+            {
+                log.WriteInfo("IIS registry key not found");
+                version = null;
+                return false;
+            }
+
+            var major = key.GetValue("MajorVersion") as int? ?? 0;
+            var minor = key.GetValue("MinorVersion") as int? ?? 0;
+
+            version = new(major: major, minor: minor);
+            return true;
+        }
+        catch (Exception ex)
+        {
+            log.WriteError(ex, $"Error reading the IIS Version from the registry key '{registryKeyName}'");
+            version = null;
+            return false;
+        }
+    }
 }