Added support for controller action parameter validation into the ValidateModelStateAttribute (#7156)

modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/AspNetCoreServerCodegen.java

@@ -125,8 +125,8 @@ public class AspNetCoreServerCodegen extends AbstractCSharpCodegen {
 
         supportingFiles.add(new SupportingFile("Properties" + File.separator + "launchSettings.json", packageFolder + File.separator + "Properties", "launchSettings.json"));
 
-        supportingFiles.add(new SupportingFile("Filters" + File.separator + "BasePathDocumentFilter.mustache", packageFolder + File.separator + "Filters", "BasePathDocumentFilter.cs"));
+        supportingFiles.add(new SupportingFile("Filters" + File.separator + "BasePathFilter.mustache", packageFolder + File.separator + "Filters", "BasePathFilter.cs"));
-        supportingFiles.add(new SupportingFile("Filters" + File.separator + "PathParameterValidationFilter.mustache", packageFolder + File.separator + "Filters", "PathParameterValidationFilter.cs"));
+        supportingFiles.add(new SupportingFile("Filters" + File.separator + "GeneratePathParamsValidationFilter.mustache", packageFolder + File.separator + "Filters", "GeneratePathParamsValidationFilter.cs"));
 
         supportingFiles.add(new SupportingFile("wwwroot" + File.separator + "README.md", packageFolder + File.separator + "wwwroot", "README.md"));
         supportingFiles.add(new SupportingFile("wwwroot" + File.separator + "index.html", packageFolder + File.separator + "wwwroot", "index.html"));

modules/swagger-codegen/src/main/resources/aspnetcore/Filters/BasePathFilter.mustache

@@ -8,13 +8,13 @@ namespace {{packageName}}.Filters
     /// <summary>
     /// BasePath Document Filter sets BasePath property of Swagger and removes it from the individual URL paths
     /// </summary>
-    public class BasePathDocumentFilter : IDocumentFilter
+    public class BasePathFilter : IDocumentFilter
     {
         /// <summary>
         /// Constructor
         /// </summary>
         /// <param name="basePath">BasePath to remove from Operations</param>
-        public BasePathDocumentFilter(string basePath)
+        public BasePathFilter(string basePath)
         {
             BasePath = basePath;
         }

modules/swagger-codegen/src/main/resources/aspnetcore/Filters/GeneratePathParamsValidationFilter.mustache

@@ -7,9 +7,9 @@ using Swashbuckle.AspNetCore.SwaggerGen;
 namespace {{packageName}}.Filters
 {
     /// <summary>
-    /// Path Parameter Validation Filter
+    /// Path Parameter Validation Rules Filter
     /// </summary>
-    public class PathParameterValidationFilter : IOperationFilter
+    public class GeneratePathParamsValidationFilter : IOperationFilter
     {
         /// <summary>
         /// Constructor

modules/swagger-codegen/src/main/resources/aspnetcore/Startup.mustache

@@ -72,10 +72,12 @@ namespace {{packageName}}
                     c.IncludeXmlComments($"{AppContext.BaseDirectory}{Path.DirectorySeparatorChar}{_hostingEnv.ApplicationName}.xml");
                     {{#basePathWithoutHost}}
                     // Sets the basePath property in the Swagger document generated
-                    c.DocumentFilter<BasePathDocumentFilter>("{{{basePathWithoutHost}}}");
+                    c.DocumentFilter<BasePathFilter>("{{{basePathWithoutHost}}}");
                     {{/basePathWithoutHost}}
-                    // Do validation of path parameters w. DataAnnotation attributes
+
-                    c.OperationFilter<PathParameterValidationFilter>();
+                    // Include DataAnnotation attributes on Controller Action parameters as Swagger validation rules (e.g required, pattern, ..)
+                    // Use [ValidateModelState] on Actions to actually validate it in C# as well!
+                    c.OperationFilter<GeneratePathParamsValidationFilter>();
                 });
         }
 

modules/swagger-codegen/src/main/resources/aspnetcore/validateModel.mustache

@@ -1,5 +1,9 @@
+using System.ComponentModel.DataAnnotations;
+using System.Reflection;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Controllers;
 using Microsoft.AspNetCore.Mvc.Filters;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
 
 namespace {{packageName}}.Attributes
 {
@@ -14,10 +18,44 @@ namespace {{packageName}}.Attributes
         /// <param name="context"></param>
         public override void OnActionExecuting(ActionExecutingContext context)
         {
+            // Per https://blog.markvincze.com/how-to-validate-action-parameters-with-dataannotation-attributes/
+            var descriptor = context.ActionDescriptor as ControllerActionDescriptor;
+            if (descriptor != null)
+            {
+                foreach (var parameter in descriptor.MethodInfo.GetParameters())
+                {
+                    object args = null;
+                    if (context.ActionArguments.ContainsKey(parameter.Name))
+                    { 
+                        args = context.ActionArguments[parameter.Name];
+                    }
+
+                    ValidateAttributes(parameter, args, context.ModelState);
+                }
+            }
+
             if (!context.ModelState.IsValid)
             {
                 context.Result = new BadRequestObjectResult(context.ModelState);
             }
         }
+
+        private void ValidateAttributes(ParameterInfo parameter, object args, ModelStateDictionary modelState)
+        {
+            foreach (var attributeData in parameter.CustomAttributes)
+            {
+                var attributeInstance = parameter.GetCustomAttribute(attributeData.AttributeType);
+
+                var validationAttribute = attributeInstance as ValidationAttribute;
+                if (validationAttribute != null)
+                {
+                    var isValid = validationAttribute.IsValid(args);
+                    if (!isValid)
+                    {
+                        modelState.AddModelError(parameter.Name, validationAttribute.FormatErrorMessage(parameter.Name));
+                    }
+                }
+            }
+        }
     }
-}
+}

samples/server/petstore/aspnetcore/src/IO.Swagger/Attributes/ValidateModelStateAttribute.cs

@@ -1,5 +1,9 @@
+using System.ComponentModel.DataAnnotations;
+using System.Reflection;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Controllers;
 using Microsoft.AspNetCore.Mvc.Filters;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
 
 namespace IO.Swagger.Attributes
 {
@@ -14,10 +18,44 @@ namespace IO.Swagger.Attributes
         /// <param name="context"></param>
         public override void OnActionExecuting(ActionExecutingContext context)
         {
+            // Per https://blog.markvincze.com/how-to-validate-action-parameters-with-dataannotation-attributes/
+            var descriptor = context.ActionDescriptor as ControllerActionDescriptor;
+            if (descriptor != null)
+            {
+                foreach (var parameter in descriptor.MethodInfo.GetParameters())
+                {
+                    object args = null;
+                    if (context.ActionArguments.ContainsKey(parameter.Name))
+                    { 
+                        args = context.ActionArguments[parameter.Name];
+                    }
+
+                    ValidateAttributes(parameter, args, context.ModelState);
+                }
+            }
+
             if (!context.ModelState.IsValid)
             {
                 context.Result = new BadRequestObjectResult(context.ModelState);
             }
         }
+
+        private void ValidateAttributes(ParameterInfo parameter, object args, ModelStateDictionary modelState)
+        {
+            foreach (var attributeData in parameter.CustomAttributes)
+            {
+                var attributeInstance = parameter.GetCustomAttribute(attributeData.AttributeType);
+
+                var validationAttribute = attributeInstance as ValidationAttribute;
+                if (validationAttribute != null)
+                {
+                    var isValid = validationAttribute.IsValid(args);
+                    if (!isValid)
+                    {
+                        modelState.AddModelError(parameter.Name, validationAttribute.FormatErrorMessage(parameter.Name));
+                    }
+                }
+            }
+        }
     }
-}
+}

samples/server/petstore/aspnetcore/src/IO.Swagger/Filters/BasePathFilter.cs

@@ -8,13 +8,13 @@ namespace IO.Swagger.Filters
     /// <summary>
     /// BasePath Document Filter sets BasePath property of Swagger and removes it from the individual URL paths
     /// </summary>
-    public class BasePathDocumentFilter : IDocumentFilter
+    public class BasePathFilter : IDocumentFilter
     {
         /// <summary>
         /// Constructor
         /// </summary>
         /// <param name="basePath">BasePath to remove from Operations</param>
-        public BasePathDocumentFilter(string basePath)
+        public BasePathFilter(string basePath)
         {
             BasePath = basePath;
         }

samples/server/petstore/aspnetcore/src/IO.Swagger/Filters/GeneratePathParamsValidationFilter.cs

@@ -7,9 +7,9 @@ using Swashbuckle.AspNetCore.SwaggerGen;
 namespace IO.Swagger.Filters
 {
     /// <summary>
-    /// Path Parameter Validation Filter
+    /// Path Parameter Validation Rules Filter
     /// </summary>
-    public class PathParameterValidationFilter : IOperationFilter
+    public class GeneratePathParamsValidationFilter : IOperationFilter
     {
         /// <summary>
         /// Constructor

samples/server/petstore/aspnetcore/src/IO.Swagger/Startup.cs

@@ -80,9 +80,11 @@ namespace IO.Swagger
                     c.DescribeAllEnumsAsStrings();
                     c.IncludeXmlComments($"{AppContext.BaseDirectory}{Path.DirectorySeparatorChar}{_hostingEnv.ApplicationName}.xml");
                     // Sets the basePath property in the Swagger document generated
-                    c.DocumentFilter<BasePathDocumentFilter>("/v2");
+                    c.DocumentFilter<BasePathFilter>("/v2");
-                    // Do validation of path parameters w. DataAnnotation attributes
+
-                    c.OperationFilter<PathParameterValidationFilter>();
+                    // Include DataAnnotation attributes on Controller Action parameters as Swagger validation rules (e.g required, pattern, ..)
+                    // Use [ValidateModelState] on Actions to actually validate it in C# as well!
+                    c.OperationFilter<GeneratePathParamsValidationFilter>();
                 });
         }