allow to customize the file header content (#5091)

* allow to customize the file header content

* add some documents

* fix test failure

readme.md

@@ -50,6 +50,7 @@ ___
     - [Change operation accessibility in bulk](#change-operation-accessibility-in-bulk)
     - [Exclude models from namespace](#exclude-models-from-namespace)
     - [Extending a model with additional constructors](#extending-a-model-with-additional-constructors)
+    - [Change the file license header](#change-the-file-license-header)
   - [Management plane concepts and configurations](#management-plane-concepts-and-configurations)
 
 <!-- /TOC -->
@@ -1788,6 +1789,16 @@ namespace Azure.Service.Models
 
 </details>
 
+### Change the file license header
+
+<details>
+Add the `--custom-header="// Your header content\n"` option to the autorest command, or add the following configuration in your `md` file for autorest
+```yaml
+custom-header: "// Your header content\n"
+```
+to change the file license headers in all generated files.
+</details>
+
 <details>
  <summary>Repository-specific pipeline configuration</summary>
 

src/AutoRest.CSharp/Common/Input/AzureApiTypes.cs

@@ -88,7 +88,7 @@ public override ValueExpression GetKeySampleExpression(string clientName)
 
         public override ExtensibleSnippets ExtensibleSnippets { get; } = new AzureExtensibleSnippets();
 
-        public override string LicenseString => """
+        public override string LicenseString => Configuration.CustomHeader ?? """
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 

src/AutoRest.CSharp/Common/Input/Configuration.cs

@@ -66,6 +66,7 @@ public static class Options
             public const string EnableInternalRawData = "enable-internal-raw-data";
             public const string HelperNamespace = "helper-namespace";
             public const string DisableXmlDocs = "disable-xml-docs";
+            public const string CustomHeader = "custom-header";
         }
 
         public enum UnreferencedTypesHandlingOption
@@ -117,7 +118,8 @@ public static void Initialize(
             bool generateSampleProject,
             bool generateTestProject,
             string? examplesDirectory,
-            string? helperNamespace)
+            string? helperNamespace,
+            string? customHeader)
         {
             _outputFolder = outputFolder;
             _namespace = ns;
@@ -191,6 +193,7 @@ public static void Initialize(
             GenerateSampleProject = DisableXmlDocs ? false : generateSampleProject; // turn off the samples if all xml docs are explicitly disabled
             GenerateTestProject = generateTestProject;
             ExamplesDirectory = examplesDirectory;
+            CustomHeader = customHeader;
             _helperNamespace = helperNamespace ?? Namespace;
         }
 
@@ -249,6 +252,8 @@ internal static (string AbsoluteProjectFolder, string RelativeProjectFolder) Par
         private static string? _helperNamespace;
         public static string HelperNamespace => _helperNamespace ?? throw new InvalidOperationException("Configuration has not been initialized");
 
+        public static string? CustomHeader { get; private set; }
+
         public static bool DisableXmlDocs { get; private set; }
 
         public static bool GenerateSampleProject { get; private set; }
@@ -396,7 +401,8 @@ public static void Initialize(IPluginCommunication autoRest, string defaultNames
                 generateTestProject: GetOptionBoolValue(autoRest, Options.GenerateTestProject),
                 examplesDirectory: null, // TODO -- what we put here?
                 helperNamespace: autoRest.GetValue<string?>(Options.HelperNamespace).GetAwaiter().GetResult(),
-                disableXmlDocs: GetOptionBoolValue(autoRest, Options.DisableXmlDocs)
+                disableXmlDocs: GetOptionBoolValue(autoRest, Options.DisableXmlDocs),
+                customHeader: autoRest.GetValue<string?>(Options.CustomHeader).GetAwaiter().GetResult()
             );
         }
 
@@ -569,12 +575,12 @@ internal static void LoadConfiguration(JsonElement root, string? projectPath, st
                 mgmtConfiguration: MgmtConfiguration.LoadConfiguration(root),
                 mgmtTestConfiguration: MgmtTestConfiguration.LoadConfiguration(root),
                 flavor: ReadStringOption(root, Options.Flavor),
-                disableXmlDocs: ReadOption(root, Options.DisableXmlDocs)
-,
+                disableXmlDocs: ReadOption(root, Options.DisableXmlDocs),
                 generateSampleProject: ReadOption(root, Options.GenerateSampleProject),
                 generateTestProject: ReadOption(root, Options.GenerateTestProject),
                 examplesDirectory: ReadStringOption(root, Options.ExamplesDirectory),
-                helperNamespace: ReadStringOption(root, Options.HelperNamespace));
+                helperNamespace: ReadStringOption(root, Options.HelperNamespace),
+                customHeader: ReadStringOption(root, Options.CustomHeader));
         }
 
         internal static string SaveConfiguration()
@@ -644,6 +650,7 @@ private static void WriteConfiguration(Utf8JsonWriter writer)
             WriteIfNotDefault(writer, Options.GenerateTestProject, GenerateTestProject);
             WriteIfNotDefault(writer, Options.HelperNamespace, HelperNamespace);
             WriteIfNotDefault(writer, Options.DisableXmlDocs, DisableXmlDocs);
+            WriteIfNotDefault(writer, Options.CustomHeader, CustomHeader);
 
             writer.WriteEndObject();
         }

src/AutoRest.CSharp/Common/Input/SystemApiTypes.cs

@@ -8,7 +8,6 @@
 using AutoRest.CSharp.Common.Output.Expressions.KnownValueExpressions;
 using AutoRest.CSharp.Common.Output.Expressions.System;
 using AutoRest.CSharp.Common.Output.Expressions.ValueExpressions;
-using AutoRest.CSharp.Common.Output.Models.Types.HelperTypeProviders;
 using AutoRest.CSharp.Generation.Types;
 using AutoRest.CSharp.Generation.Writers;
 using AutoRest.CSharp.Output.Models;
@@ -99,7 +98,7 @@ public override ValueExpression GetKeySampleExpression(string clientName)
 
         public override ExtensibleSnippets ExtensibleSnippets { get; } = new SystemExtensibleSnippets();
 
-        public override string LicenseString => string.Empty;
+        public override string LicenseString => Configuration.CustomHeader ?? string.Empty;
 
         public override string ResponseClassifierIsErrorResponseName => nameof(PipelineMessageClassifier.TryClassify);
     }

test/AutoRest.TestServer.Tests/Common/Utilities/NamedTypeSymbolExtensionsTests.cs

@@ -116,7 +116,8 @@ public void Method(int? nullableInt, List<int> intList, List<int?> nullableIntLi
                 generateSampleProject: true,
                 generateTestProject: true,
                 examplesDirectory: null,
-                helperNamespace: "");
+                helperNamespace: "",
+                customHeader: null);
         }
 
         [Test]

test/AutoRest.TestServer.Tests/Mgmt/Unit/MgmtRestOperationTests.cs

@@ -93,7 +93,8 @@ public void Setup()
                 generateSampleProject: true,
                 generateTestProject: true,
                 examplesDirectory: null,
-                helperNamespace: "");
+                helperNamespace: "",
+                customHeader: null);
         }
 
         private void TestPair(ResourceMatchType expected, string httpMethod, string resourcePathStr, string requestPathStr, bool isList)

test/AutoRest.TestServerLowLevel.Tests/LowLevel/Generation/ModelGenerationTestBase.cs

@@ -74,7 +74,8 @@ public void Initialize()
                 generateSampleProject: true,
                 generateTestProject: true,
                 examplesDirectory: null,
-                helperNamespace: "");
+                helperNamespace: "",
+                customHeader: null);
         }