@@ -12,12 +12,17 @@ )
 
 type user struct{}
 
+var (
+	ErrCannotDetermineUser = ihttp.NewError("cannot determine user", http.StatusInternalServerError)
+	ErrRenderFailure       = ihttp.NewError("failed to render page", http.StatusInternalServerError)
+)
+
 func (app *App) WithUserContext(fn ihttp.HandleFunc) ihttp.HandleFunc {
 	return func(w http.ResponseWriter, r *http.Request) ihttp.Error {
 		ctx := r.Context()
 		who, err := app.localClient.WhoIs(ctx, r.RemoteAddr)
 		if err != nil {
-			return ihttp.InternalServerError("cannot determine user", err)
+			return ErrCannotDetermineUser
 		}
 
 		return fn(w, r.WithContext(
@@ -35,7 +40,7 @@ },
 		User: user.LoginName,
 	}).Render(w)
 	if err != nil {
-		return ihttp.InternalServerError("Failed to render index page", err)
+		return ErrRenderFailure
 	}
 
 	return nil

@@ -21,6 +21,18 @@ providers  []ResourceProvider
 	corsOrigin string
 }
 
+var (
+	ErrMissingResourceParameter = ihttp.NewError(
+		"Missing resource parameter",
+		http.StatusBadRequest,
+	)
+	ErrFailedToEncodeResponse = ihttp.NewError(
+		"Failed to encode webfinger response",
+		http.StatusInternalServerError,
+	)
+	ErrNotFound = ihttp.NewError("Resource not found", http.StatusNotFound)
+)
+
 type Option func(*Service)
 
 func WithCORSOrigin(origin string) Option {
@@ -50,7 +62,7 @@
 func (s *Service) HandleFunc(w http.ResponseWriter, r *http.Request) ihttp.Error {
 	resource := r.URL.Query().Get("resource")
 	if resource == "" {
-		return ihttp.BadRequest("Missing resource parameter", nil)
+		return ErrMissingResourceParameter
 	}
 
 	for _, provider := range s.providers {
@@ -62,12 +74,12 @@ w.Header().Add("Access-Control-Allow-Origin", s.corsOrigin)
 			}
 
 			if err := json.NewEncoder(w).Encode(provider.GetIdentityResource()); err != nil {
-				return ihttp.InternalServerError("Failed to encode webfinger response", err)
+				return ErrFailedToEncodeResponse.WithCause(err)
 			}
 
 			return nil
 		}
 	}
 
-	return ihttp.NotFound("Resource not found")
+	return ErrNotFound
 }

@@ -15,6 +15,12 @@
 	"github.com/kevinpollet/nego"
 )
 
+var (
+	ErrReadingFile   = ihttp.NewError("Error reading file", http.StatusInternalServerError)
+	ErrNotFound      = ihttp.NewError("File not found", http.StatusNotFound)
+	ErrRenderFailure = ihttp.NewError("Error rendering template", http.StatusInternalServerError)
+)
+
 func (website *Website) ErrorHandler(err ihttp.Error, w http.ResponseWriter, r *http.Request) {
 	if strings.Contains(r.Header.Get("Accept"), "text/html") {
 		w.WriteHeader(err.StatusCode())
@@ -42,10 +48,10 @@ file, err := website.reader.GetFile(urlPath)
 	if err != nil {
 		website.log.Warn("Error reading file", "error", err)
 
-		return ihttp.InternalServerError("Error reading file", err)
+		return ErrReadingFile.WithCause(err)
 	}
 	if file == nil {
-		return ihttp.NotFound("File not found")
+		return ErrNotFound
 	}
 	analytics.WithTitle(r, file.Title)
 	w.Header().Add("ETag", file.Etag)
@@ -72,7 +78,7 @@ func (website *Website) Calendar(w http.ResponseWriter, r *http.Request) ihttp.Error {
 	analytics.WithTitle(r, "Calendar")
 	err := calendar.CalendarPage(*website.siteSettings, website.calendar).Render(w)
 	if err != nil {
-		return ihttp.InternalServerError("could not render calendar page", err)
+		return ErrRenderFailure.WithCause(err)
 	}
 
 	return nil

@@ -18,7 +18,7 @@ message string
 	cause   error
 }
 
-func (e *httpError) Error() string {
+func (e httpError) Error() string {
 	if e.message == "" {
 		e.message = http.StatusText(e.code)
 	}
@@ -26,11 +26,11 @@
 	return fmt.Sprintf("%d %s", e.code, e.message)
 }
 
-func (e *httpError) StatusCode() int {
+func (e httpError) StatusCode() int {
 	return e.code
 }
 
-func (e *httpError) Message() string {
+func (e httpError) Message() string {
 	if e.message == "" {
 		e.message = http.StatusText(e.code)
 	}
@@ -38,53 +38,21 @@
 	return e.message
 }
 
-func (e *httpError) Unwrap() error {
+func (e httpError) Unwrap() error {
 	return e.cause
 }
 
-func NewError(code int, message string, cause error) Error {
-	return &httpError{
+func NewError(message string, code int) httpError {
+	return httpError{
 		code:    code,
 		message: message,
-		cause:   cause,
 	}
 }
 
-func NotFound(message string) Error {
-	return &httpError{
-		code:    http.StatusNotFound,
-		message: message,
-	}
-}
-
-func BadRequest(message string, cause error) Error {
-	return &httpError{
-		code:    http.StatusBadRequest,
-		message: message,
-		cause:   cause,
-	}
-}
-
-func InternalServerError(message string, cause error) Error {
-	return &httpError{
-		code:    http.StatusInternalServerError,
-		message: message,
-		cause:   cause,
-	}
-}
-
-func Unauthorized(message string, cause error) Error {
-	return &httpError{
-		code:    http.StatusUnauthorized,
-		message: message,
-		cause:   cause,
-	}
-}
-
-func Forbidden(message string, cause error) Error {
-	return &httpError{
-		code:    http.StatusForbidden,
-		message: message,
+func (e httpError) WithCause(cause error) Error {
+	return httpError{
+		code:    e.code,
+		message: e.message,
 		cause:   cause,
 	}
 }