Adding error list support

Author: Derek Dowling

document.go

@@ -13,7 +13,7 @@ of each attribute: http://jsonapi.org/format/#document-structure
 */
 type Document struct {
 	Data     List        `json:"data,omitempty"`
-	Errors   []*Error    `json:"errors,omitempty"`
+	Errors   ErrorList   `json:"errors,omitempty"`
 	Links    *Link       `json:"links,omitempty"`
 	Included []*Object   `json:"included,omitempty"`
 	Meta     interface{} `json:"meta,omitempty"`
@@ -62,10 +62,16 @@ func Build(payload Sendable) *Document {
 
 	err, isError := payload.(*Error)
 	if isError {
-		document.Errors = []*Error{err}
+		document.Errors = ErrorList{err}
 		document.Status = err.Status
 	}
 
+	errorList, isErrorList := payload.(ErrorList)
+	if isErrorList {
+		document.Errors = errorList
+		document.Status = errorList[0].Status
+	}
+
 	return document
 }
 
@@ -103,11 +109,9 @@ func (d *Document) Validate(r *http.Request, response bool) *Error {
 		return err
 	}
 
-	for _, docErr := range d.Errors {
-		err := docErr.Validate(r, response)
-		if err != nil {
-			return err
-		}
+	err = d.Errors.Validate(r, response)
+	if err != nil {
+		return err
 	}
 
 	return nil

error.go

@@ -16,6 +16,21 @@ var DefaultErrorDetail = "Request failed, something went wrong."
 // DefaultTitle can be customized to provide a more customized ISE Title
 var DefaultErrorTitle = "Internal Server Error"
 
+// ErrorList is wraps an Error Array so that it can implement Sendable
+type ErrorList []*Error
+
+// Validate checks all errors within the list to ensure that they are valid
+func (e ErrorList) Validate(r *http.Request, response bool) *Error {
+	for _, err := range e {
+		validationErr := err.Validate(r, response)
+		if validationErr != nil {
+			return validationErr
+		}
+	}
+
+	return nil
+}
+
 /*
 Error consists of a number of contextual attributes to make conveying
 certain error type simpler as per the JSON API specification:

error_test.go

@@ -70,6 +70,20 @@ func TestError(t *testing.T) {
 				So(contentLength, ShouldBeGreaterThan, 0)
 				So(writer.HeaderMap.Get("Content-Type"), ShouldEqual, ContentType)
 			})
+
+			Convey("should work for an ErrorList", func() {
+
+				errorList := ErrorList{testError}
+
+				err := Send(writer, request, errorList)
+				So(err, ShouldBeNil)
+				So(writer.Code, ShouldEqual, http.StatusForbidden)
+
+				contentLength, convErr := strconv.Atoi(writer.HeaderMap.Get("Content-Length"))
+				So(convErr, ShouldBeNil)
+				So(contentLength, ShouldBeGreaterThan, 0)
+				So(writer.HeaderMap.Get("Content-Type"), ShouldEqual, ContentType)
+			})
 		})
 	})
 }

object.go

@@ -63,7 +63,7 @@ specifying each struct attribute that failed. In this case, all you need to do i
 		jsh.Send(w, r, errors)
 	}
 */
-func (o *Object) Unmarshal(resourceType string, target interface{}) []*Error {
+func (o *Object) Unmarshal(resourceType string, target interface{}) ErrorList {
 
 	if resourceType != o.Type {
 		return []*Error{ISE(fmt.Sprintf(
@@ -172,15 +172,15 @@ func (o *Object) String() string {
 
 // validateInput runs go-validator on each attribute on the struct and returns all
 // errors that it picks up
-func validateInput(target interface{}) []*Error {
+func validateInput(target interface{}) ErrorList {
 
 	_, validationError := govalidator.ValidateStruct(target)
 	if validationError != nil {
 
 		errorList, isType := validationError.(govalidator.Errors)
 		if isType {
 
-			errors := []*Error{}
+			errors := ErrorList{}
 			for _, singleErr := range errorList.Errors() {
 
 				// parse out validation error