Validation should return 400 on fail (#30)

New BadRequestError type : returns 400 status code on Validation failure
Instead of 500 previously

---------

Co-authored-by: EwenQuim <ewen.quimerch@gmail.com>

ctx.go

@@ -17,6 +17,7 @@ const (
 
 // Ctx is the context of the request.
 // It contains the request body, the path parameters, the query parameters, and the http request.
+// Please do not use a pointer type as parameter.
 type Ctx[B any] interface {
 	// Body returns the body of the request.
 	// If (*B) implements [InTransformer], it will be transformed after deserialization.
@@ -79,6 +80,7 @@ type Ctx[B any] interface {
 	Pass() ClassicContext
 }
 
+// NewContext returns a new context. It is used internally by Fuego. You probably want to use Ctx[B] instead.
 func NewContext[B any](w http.ResponseWriter, r *http.Request, options readOptions) *Context[B] {
 	c := &Context[B]{
 		ClassicContext: ClassicContext{
@@ -94,6 +96,7 @@ func NewContext[B any](w http.ResponseWriter, r *http.Request, options readOptio
 	return c
 }
 
+// Context is used internally by Fuego. You probably want to use Ctx[B] instead. Please do not use a pointer type as parameter.
 type Context[BodyType any] struct {
 	body *BodyType
 	ClassicContext
@@ -103,22 +106,22 @@ func (c *Context[B]) Pass() ClassicContext {
 	return c.ClassicContext
 }
 
-// ClassicContext for the request. BodyType is the type of the request body. Please do not use a pointer type as parameter.
+// ClassicContext is used internally by Fuego. Please do not use a pointer type as parameter.
 type ClassicContext struct {
 	request    *http.Request
 	response   http.ResponseWriter
 	pathParams map[string]string
 
-	fs              fs.FS
-	templates       *template.Template
-	templatesParsed bool
+	fs        fs.FS
+	templates *template.Template
 
 	readOptions readOptions
 }
 
 func (c ClassicContext) Body() (any, error) {
 	panic("this method should not be called. It probably happened because you passed the context to another controller with the Pass method.")
 }
+
 func (c ClassicContext) MustBody() any {
 	b, err := c.Body()
 	if err != nil {
@@ -146,8 +149,11 @@ type readOptions struct {
 	LogBody               bool
 }
 
-var _ Ctx[any] = &Context[any]{}   // Check that Context implements Ctx.
-var _ Ctx[any] = &ClassicContext{} // Check that Context implements Ctx.
+var (
+	_ Ctx[any]    = &Context[any]{}    // Check that Context implements Ctx.
+	_ Ctx[string] = &Context[string]{} // Check that Context implements Ctx.
+	_ Ctx[any]    = &ClassicContext{}  // Check that Context implements Ctx.
+)
 
 // Context returns the context of the request.
 // Same as c.Request().Context().
@@ -174,14 +180,13 @@ func (c ClassicContext) Pass() ClassicContext {
 // the need to parse the templates on each request but also preventing
 // to dynamically use new templates.
 func (c ClassicContext) Render(templateToExecute string, data any, layoutsGlobs ...string) (HTML, error) {
-	if !c.templatesParsed &&
-		(strings.Contains(templateToExecute, "/") || strings.Contains(templateToExecute, "*")) {
+	if strings.Contains(templateToExecute, "/") || strings.Contains(templateToExecute, "*") {
 
 		layoutsGlobs = append(layoutsGlobs, templateToExecute) // To override all blocks defined in the main template
 		cloned := template.Must(c.templates.Clone())
 		tmpl, err := cloned.ParseFS(c.fs, layoutsGlobs...)
 		if err != nil {
-			return "", ErrorResponse{
+			return "", HTTPError{
 				StatusCode: http.StatusInternalServerError,
 				Message:    fmt.Errorf("error parsing template '%s': %w", layoutsGlobs, err).Error(),
 				MoreInfo: map[string]any{
@@ -191,7 +196,6 @@ func (c ClassicContext) Render(templateToExecute string, data any, layoutsGlobs
 			}
 		}
 		c.templates = template.Must(tmpl.Clone())
-		c.templatesParsed = true
 	}
 
 	// Get only last template name (for example, with partials/nav/main/nav.partial.html, get nav.partial.html)
@@ -201,7 +205,7 @@ func (c ClassicContext) Render(templateToExecute string, data any, layoutsGlobs
 	c.response.Header().Set("Content-Type", "text/html; charset=utf-8")
 	err := c.templates.ExecuteTemplate(c.response, templateToExecute, data)
 	if err != nil {
-		return "", ErrorResponse{
+		return "", HTTPError{
 			StatusCode: http.StatusInternalServerError,
 			Message:    fmt.Errorf("error executing template '%s': %w", templateToExecute, err).Error(),
 			MoreInfo: map[string]any{

deserialization.go

@@ -45,18 +45,18 @@ func readJSON[B any](input io.Reader, options readOptions) (B, error) {
 	}
 	err := dec.Decode(&body)
 	if err != nil {
-		return body, fmt.Errorf("cannot decode request body: %w", err)
+		return body, BadRequestError{Message: "cannot decode request body: " + err.Error()}
 	}
 	slog.Debug("Decoded body", "body", body)
 
 	body, err = transform(body)
 	if err != nil {
-		return body, fmt.Errorf("cannot transform request body: %w", err)
+		return body, BadRequestError{Message: "cannot transform request body: " + err.Error()}
 	}
 
 	err = validate(body)
 	if err != nil {
-		return body, fmt.Errorf("cannot validate request body: %w", err)
+		return body, BadRequestError{Message: "cannot validate request body: " + err.Error()}
 	}
 
 	return body, nil
@@ -73,7 +73,7 @@ func readString[B ~string](input io.Reader, options readOptions) (B, error) {
 	// Read the request body.
 	readBody, err := io.ReadAll(input)
 	if err != nil {
-		return "", fmt.Errorf("cannot read request body: %w", err)
+		return "", BadRequestError{Message: "cannot read request body: " + err.Error()}
 	}
 
 	body := B(readBody)
@@ -150,7 +150,7 @@ func transform[B any](body B) (B, error) {
 	if inTransformerBody, ok := any(&body).(InTransformer); ok {
 		err := inTransformerBody.InTransform()
 		if err != nil {
-			return body, fmt.Errorf("cannot transform request body: %w", err)
+			return body, BadRequestError{Message: "cannot transform request body: " + err.Error()}
 		}
 		body = *any(inTransformerBody).(*B)
 

deserialization_test.go

@@ -26,7 +26,7 @@ func TestReadJSON(t *testing.T) {
 
 	t.Run("cannot read invalid JSON", func(t *testing.T) {
 		_, err := ReadJSON[TestBody](input)
-		require.Error(t, err)
+		require.ErrorAs(t, err, &BadRequestError{}, "Expected a BadRequestError")
 	})
 
 	t.Run("cannot deserialize JSON to wrong struct", func(t *testing.T) {
@@ -36,7 +36,7 @@ func TestReadJSON(t *testing.T) {
 			// Missing C bool
 		}
 		_, err := ReadJSON[WrongBody](input)
-		require.Error(t, err)
+		require.ErrorAs(t, err, &BadRequestError{}, "Expected a BadRequestError")
 	})
 }
 
@@ -127,7 +127,7 @@ func TestInTransformStringWithError(t *testing.T) {
 	t.Run("ReadString", func(t *testing.T) {
 		input := strings.NewReader(`coucou`)
 		body, err := ReadString[transformableStringWithError](input)
-		require.Error(t, err)
+		require.ErrorAs(t, err, &BadRequestError{}, "Expected a BadRequestError")
 		require.Equal(t, transformableStringWithError("transformed coucou"), body)
 	})
 }

errors.go

@@ -20,37 +20,63 @@ type ErrorWithInfo interface {
 	Info() map[string]any
 }
 
-// ErrorResponse is the error response used by the serialization part of the framework.
-type ErrorResponse struct {
+// HTTPError is the error response used by the serialization part of the framework.
+type HTTPError struct {
+	Err        error          `json:",omitempty"`                          // backend developer readable error message
 	Message    string         `json:"error" xml:"Error"`                   // human readable error message
 	StatusCode int            `json:"-" xml:"-"`                           // http status code
 	MoreInfo   map[string]any `json:"info,omitempty" xml:"Info,omitempty"` // additional info
 }
 
-func (e ErrorResponse) Error() string {
+var (
+	_ ErrorWithInfo   = HTTPError{}
+	_ ErrorWithStatus = HTTPError{}
+)
+
+func (e HTTPError) Error() string {
 	return e.Message
 }
 
-var _ ErrorWithStatus = ErrorResponse{}
+func (e HTTPError) Info() map[string]any {
+	return e.MoreInfo
+}
 
-func (e ErrorResponse) Status() int {
+func (e HTTPError) Status() int {
 	if e.StatusCode == 0 {
 		return http.StatusInternalServerError
 	}
 	return e.StatusCode
 }
 
-var _ ErrorWithInfo = ErrorResponse{}
+// BadRequestError is an error used to return a 400 status code.
+type BadRequestError struct {
+	Err      error          // developer readable error message
+	Message  string         `json:"error" xml:"Error"`                   // human readable error message
+	MoreInfo map[string]any `json:"info,omitempty" xml:"Info,omitempty"` // additional info
+}
+
+var (
+	_ ErrorWithInfo   = BadRequestError{}
+	_ ErrorWithStatus = BadRequestError{}
+)
+
+func (e BadRequestError) Error() string {
+	return e.Message
+}
 
-func (e ErrorResponse) Info() map[string]any {
+func (e BadRequestError) Info() map[string]any {
 	return e.MoreInfo
 }
 
+func (e BadRequestError) Status() int {
+	return http.StatusBadRequest
+}
+
 // ErrorHandler is the default error handler used by the framework.
-// It transforms any error into the unified error type [ErrorResponse],
+// It transforms any error into the unified error type [HTTPError],
 // Using the [ErrorWithStatus] and [ErrorWithInfo] interfaces.
 func ErrorHandler(err error) error {
-	errResponse := ErrorResponse{
+	errResponse := HTTPError{
 		Message: err.Error(),
 	}
 

errors_test.go

@@ -20,35 +20,35 @@ func TestErrorHandler(t *testing.T) {
 		err := errors.New("test error")
 
 		errResponse := ErrorHandler(err)
-		require.ErrorAs(t, errResponse, &ErrorResponse{})
+		require.ErrorAs(t, errResponse, &HTTPError{})
 		require.Equal(t, "test error", errResponse.Error())
-		require.Equal(t, http.StatusInternalServerError, errResponse.(ErrorResponse).Status())
-		require.Nil(t, errResponse.(ErrorResponse).Info())
+		require.Equal(t, http.StatusInternalServerError, errResponse.(HTTPError).Status())
+		require.Nil(t, errResponse.(HTTPError).Info())
 	})
 
 	t.Run("error with status ", func(t *testing.T) {
 		err := myError{
 			status: http.StatusNotFound,
 		}
 		errResponse := ErrorHandler(err)
-		require.ErrorAs(t, errResponse, &ErrorResponse{})
+		require.ErrorAs(t, errResponse, &HTTPError{})
 		require.Equal(t, "test error", errResponse.Error())
-		require.Equal(t, http.StatusNotFound, errResponse.(ErrorResponse).Status())
-		require.Nil(t, errResponse.(ErrorResponse).Info())
+		require.Equal(t, http.StatusNotFound, errResponse.(HTTPError).Status())
+		require.Nil(t, errResponse.(HTTPError).Info())
 	})
 
 	t.Run("error with status and info", func(t *testing.T) {
-		err := ErrorResponse{
+		err := HTTPError{
 			Message:    "test error",
 			StatusCode: http.StatusNotFound,
 			MoreInfo: map[string]any{
 				"test": "info",
 			},
 		}
 		errResponse := ErrorHandler(err)
-		require.ErrorAs(t, errResponse, &ErrorResponse{})
+		require.ErrorAs(t, errResponse, &HTTPError{})
 		require.Equal(t, "test error", errResponse.Error())
-		require.Equal(t, http.StatusNotFound, errResponse.(ErrorResponse).Status())
-		require.NotNil(t, errResponse.(ErrorResponse).Info())
+		require.Equal(t, http.StatusNotFound, errResponse.(HTTPError).Status())
+		require.NotNil(t, errResponse.(HTTPError).Info())
 	})
 }

examples/simple-crud/errors_custom.go

@@ -0,0 +1,11 @@
+package main
+
+import "net/http"
+
+type MyError struct {
+	Err error // developer readable error message
+}
+
+func (e MyError) Status() int {
+	return http.StatusTeapot
+}

examples/simple-crud/store/ingredient.go

@@ -60,5 +60,4 @@ func (i Ingredient) Months() string {
 	}
 
 	return strings.Join(months, ", ")
-
 }

examples/simple-crud/views/admin.go

@@ -155,7 +155,6 @@ func (rs Ressource) adminAddDosing(c fuego.Ctx[store.CreateDosingParams]) (any,
 }
 
 func (rs Ressource) adminIngredients(c fuego.Ctx[any]) (any, error) {
-
 	searchParams := components.SearchParams{
 		Name:    c.QueryParam("name"),
 		PerPage: c.QueryParamInt("perPage", 10),

middleware/basicauth/basicauth.go

@@ -29,7 +29,7 @@ func New(config Config) func(http.Handler) http.Handler {
 				return
 			}
 
-			err := fuego.ErrorResponse{
+			err := fuego.HTTPError{
 				Message:    "unauthorized",
 				StatusCode: http.StatusUnauthorized,
 			}

options_test.go

@@ -57,6 +57,6 @@ func TestWithXML(t *testing.T) {
 
 		require.Equal(t, 500, recorder.Code)
 		require.Equal(t, "application/xml", recorder.Header().Get("Content-Type"))
-		require.Equal(t, "<ErrorResponse><Error>error</Error></ErrorResponse>", recorder.Body.String())
+		require.Equal(t, "<HTTPError><Error>error</Error></HTTPError>", recorder.Body.String())
 	})
 }

serialization.go

@@ -93,7 +93,7 @@ func SendJSON(w http.ResponseWriter, ans any) {
 // If the error implements ErrorWithStatus, the status code will be set.
 func SendJSONError(w http.ResponseWriter, err error) {
 	status := http.StatusInternalServerError
-	errorStatus := ErrorResponse{
+	errorStatus := HTTPError{
 		Message: err.Error(),
 	}
 	if errors.As(err, &errorStatus) {

serialization_test.go

@@ -54,11 +54,11 @@ func TestXML(t *testing.T) {
 
 	t.Run("can serialize xml error", func(t *testing.T) {
 		w := httptest.NewRecorder()
-		err := ErrorResponse{Message: "Hello World"}
+		err := HTTPError{Message: "Hello World"}
 		SendXMLError(w, err)
 		body := w.Body.String()
 
-		require.Equal(t, `<ErrorResponse><Error>Hello World</Error></ErrorResponse>`, body)
+		require.Equal(t, `<HTTPError><Error>Hello World</Error></HTTPError>`, body)
 	})
 }