fix: enhance DocFX build target with improved logging and error handling

Author: DennisDyallo

Yubico.YubiKey/src/Yubico.YubiKey.csproj

@@ -157,14 +157,19 @@ limitations under the License. -->
 
   <!-- DocFX build target runs after Release-build -->
   <Target Name="CheckDocFX">
-    <Exec Command="docfx --version" EchoOff="true" ContinueOnError="true" StandardErrorImportance="High" StandardOutputImportance="High">
+    <Exec Command="docfx --version" ContinueOnError="true">
       <Output TaskParameter="ExitCode" PropertyName="DocFXExists" />
     </Exec>
     <Error Condition="'$(DocFXExists)' != '0'" Text="DocFX is not installed. Please install it using: dotnet tool install --global docfx" />
   </Target>
 
   <Target Name="DocFXBuild" AfterTargets="Build" DependsOnTargets="CheckDocFX" Condition="'$(Configuration)' == 'Release'">
-    <Exec Command="docfx build $(MSBuildProjectDirectory)/docfx.json --log docfxlogz.txt" IgnoreExitCode="true"/>
+    <Exec Command="docfx build $(MSBuildProjectDirectory)/docfx.json --logLevel warning --log docfx-log.txt --warningsAsErrors" IgnoreExitCode="true">
+      <Output TaskParameter="ExitCode" PropertyName="DocFXExitCode" />
+    </Exec>
+    <!-- Quirk. 255 seems to be the exit code it uses but we don't know the reason, so we catch it and refer to the log -->
+    <Error Condition="'$(DocFXExitCode)' != '255' AND '$(DocFXExitCode)' != '0'" 
+       Text="DocFX build failed with exit code $(DocFXExitCode). Check docfx-log.txt for details." />
   </Target>
 
 </Project>