Additonal Namespaces for generated Types

src/Refitter.Core/RefitGenerator.cs

@@ -55,6 +55,16 @@ private string GenerateClient(RefitInterfaceGenerator interfaceGenerator)
         code.AppendLine(RefitInterfaceImports.GenerateNamespaceImports(settings))
             .AppendLine();
 
+        if (settings.AdditionalNamespaces.Any())
+        {
+            foreach (var ns in settings.AdditionalNamespaces)
+            {
+                code.AppendLine($"using {ns};");
+            }
+
+            code.AppendLine();
+        }
+
         code.AppendLine($$"""
             namespace {{settings.Namespace}}
             {

src/Refitter.Core/RefitGeneratorSettings.cs

@@ -1,4 +1,5 @@
-using System.Diagnostics.CodeAnalysis;
+using System;
+using System.Diagnostics.CodeAnalysis;
 
 namespace Refitter.Core;
 
@@ -26,6 +27,8 @@ public class RefitGeneratorSettings
     public bool UseCancellationTokens { get; set; }
 
     public bool UseIsoDateFormat { get; set; }
+
+    public string[] AdditionalNamespaces { get; set; } = Array.Empty<string>();
 }
 
 [ExcludeFromCodeCoverage]

src/Refitter.Tests/Examples/AdditionalNamespacesTests.cs

@@ -0,0 +1,109 @@
+using FluentAssertions;
+using Refitter.Core;
+using Refitter.Tests.Build;
+using Xunit;
+
+namespace Refitter.Tests.Examples;
+
+public class AdditionalNamespacesTests
+{
+    private const string OpenApiSpec = @"
+{
+  ""openapi"" : ""3.0.1"",
+  ""paths"" : {
+    ""/api/v1/{id}/foo"" : {
+      ""get"" : {
+        ""tags"" : [ ""foo"" ],
+        ""operationId"" : ""get-/api/v1/{id}/foo_getAll"",
+        ""parameters"" : [ {
+          ""name"" : ""id"",
+          ""in"" : ""path"",
+          ""required"" : true,
+          ""style"" : ""simple"",
+          ""explode"" : false,
+          ""schema"" : {
+            ""type"" : ""integer"",
+            ""format"" : ""int32""
+          }
+        } ],
+        ""responses"" : {
+          ""200"" : {
+            ""description"" : ""successful operation""
+          }
+        }
+      }
+    },
+    ""/api/v1/{id}/bar"" : {
+      ""get"" : {
+        ""tags"" : [ ""bar"" ],
+        ""operationId"" : ""get-/api/v1/{id}/bar_getAll"",
+        ""parameters"" : [ {
+          ""name"" : ""id"",
+          ""in"" : ""path"",
+          ""required"" : true,
+          ""style"" : ""simple"",
+          ""explode"" : false,
+          ""schema"" : {
+            ""type"" : ""integer"",
+            ""format"" : ""int32""
+          }
+        } ],
+        ""responses"" : {
+          ""200"" : {
+            ""description"" : ""successful operation""
+          }
+        }
+      }
+    }
+  }
+}
+";
+
+    [Fact]
+    public async Task Can_Generate_Code()
+    {
+        string generateCode = await GenerateCode();
+        generateCode.Should().NotBeNullOrWhiteSpace();
+    }
+
+    [Fact]
+    public async Task Can_Build_Generated_Code()
+    {
+        string generateCode = await GenerateCode();
+        BuildHelper
+            .BuildCSharp(generateCode)
+            .Should()
+            .BeTrue();
+    }
+
+    [Fact]
+    public async Task Generated_Types_Contains_Additional_Namespaces()
+    {
+        string generateCode = await GenerateCode();
+        generateCode.Should().Contain("using System.Diagnostics.CodeAnalysis;");
+    }
+
+    private static async Task<string> GenerateCode()
+    {
+        var swaggerFile = await CreateSwaggerFile(OpenApiSpec);
+        var foo = new RefitGeneratorSettings
+        {
+            OpenApiPath = swaggerFile,
+            AdditionalNamespaces = new[] { "System.Text.Json", "System.Diagnostics.CodeAnalysis" },
+        };
+
+        var sut = await RefitGenerator.CreateAsync(foo);
+        var generateCode = sut.Generate();
+        return generateCode;
+    }
+
+    private static async Task<string> CreateSwaggerFile(string contents)
+    {
+        var filename = $"{Guid.NewGuid()}.yml";
+        var folder = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
+        Directory.CreateDirectory(folder);
+        var swaggerFile = Path.Combine(folder, filename);
+        await File.WriteAllTextAsync(swaggerFile, contents);
+        return swaggerFile;
+    }
+}

src/Refitter/GenerateCommand.cs

@@ -33,29 +33,30 @@ public override async Task<int> ExecuteAsync(CommandContext context, Settings se
             UseIsoDateFormat = settings.UseIsoDateFormat,
             TypeAccessibility = settings.InternalTypeAccessibility
                 ? TypeAccessibility.Internal
-                : TypeAccessibility.Public
+                : TypeAccessibility.Public,
+            AdditionalNamespaces = settings.AdditionalNamespaces!,
         };
 
         var crlf = Environment.NewLine;
         try
         {
             AnsiConsole.MarkupLine($"[green]Support key: {SupportInformation.GetSupportKey()}[/]");
-            
+
             var generator = await RefitGenerator.CreateAsync(refitGeneratorSettings);
             var code = generator.Generate().ReplaceLineEndings();
             AnsiConsole.MarkupLine($"[green]Length: {code.Length} bytes[/]");
-            
+
             if (!string.IsNullOrWhiteSpace(settings.OutputPath))
             {
                 var directory = Path.GetDirectoryName(settings.OutputPath);
                 if (!string.IsNullOrWhiteSpace(directory) && !Directory.Exists(directory))
                     Directory.CreateDirectory(directory);
             }
-            
+
             var outputPath = settings.OutputPath ?? "Output.cs";
             AnsiConsole.MarkupLine($"[green]Output: {Path.GetFullPath(outputPath)}{crlf}[/]");
             await File.WriteAllTextAsync(outputPath, code);
-            
+
             await Analytics.LogFeatureUsage(settings);
             return 0;
         }

src/Refitter/Program.cs

@@ -88,6 +88,16 @@
                     "./openapi.json",
                     "--use-iso-date-format"
                 });
+        configuration
+            .AddExample(
+                new[]
+                {
+                     "./openapi.json",
+                     "--additional-namespace",
+                     "\"Your.Additional.Namespace\"",
+                     "--additional-namespace",
+                     "\"Your.Other.Additional.Namespace\"",
+                });
     });
 
 return app.Run(args);

src/Refitter/Settings.cs

@@ -1,5 +1,5 @@
-using System.ComponentModel;
 using Spectre.Console.Cli;
+using System.ComponentModel;
 
 namespace Refitter;
 
@@ -58,4 +58,9 @@ public sealed class Settings : CommandSettings
     [CommandOption("--use-iso-date-format")]
     [DefaultValue(false)]
     public bool UseIsoDateFormat { get; set; }
+
+    [Description("Add additional namespace to generated types")]
+    [CommandOption("--additional-namespace")]
+    [DefaultValue(new string[0])]
+    public string[]? AdditionalNamespaces { get; set; }
 }