add x/errors.OK, Create, NoContent and NoContentOrNotModified package-level generic functions as custom service helpers

x/errors/errors.go

@@ -48,9 +48,12 @@ type (
 // A read-only map of valid http error codes.
 var errorCodeMap = make(map[ErrorCodeName]ErrorCode)
 
-// E registers a custom HTTP Error and returns its canonical name for future use.
+// Deprecated: Use Register instead.
+var E = Register
+
+// Register registers a custom HTTP Error and returns its canonical name for future use.
 // The method "New" is reserved and was kept as it is for compatibility
-// with the standard errors package, therefore the "E" name was chosen instead.
+// with the standard errors package, therefore the "Register" name was chosen instead.
 // The key stroke "e" is near and accessible while typing the "errors" word
 // so developers may find it easy to use.
 //
@@ -59,14 +62,14 @@ var errorCodeMap = make(map[ErrorCodeName]ErrorCode)
 // Example:
 //
 //		var (
-//	   		NotFound = errors.E("NOT_FOUND", http.StatusNotFound)
+//	   		NotFound = errors.Register("NOT_FOUND", http.StatusNotFound)
 //		)
 //		...
 //		NotFound.Details(ctx, "resource not found", "user with id: %q was not found", userID)
 //
 // This method MUST be called on initialization, before HTTP server starts as
 // the internal map is not protected by mutex.
-func E(httpErrorCanonicalName string, httpStatusCode int) ErrorCodeName {
+func Register(httpErrorCanonicalName string, httpStatusCode int) ErrorCodeName {
 	canonicalName := ErrorCodeName(httpErrorCanonicalName)
 	RegisterErrorCode(canonicalName, httpStatusCode)
 	return canonicalName
@@ -99,22 +102,22 @@ func RegisterErrorCodeMap(errorMap map[ErrorCodeName]int) {
 
 // List of default error codes a server should follow and send back to the client.
 var (
-	Cancelled          ErrorCodeName = E("CANCELLED", context.StatusTokenRequired)
-	Unknown            ErrorCodeName = E("UNKNOWN", http.StatusInternalServerError)
-	InvalidArgument    ErrorCodeName = E("INVALID_ARGUMENT", http.StatusBadRequest)
-	DeadlineExceeded   ErrorCodeName = E("DEADLINE_EXCEEDED", http.StatusGatewayTimeout)
-	NotFound           ErrorCodeName = E("NOT_FOUND", http.StatusNotFound)
-	AlreadyExists      ErrorCodeName = E("ALREADY_EXISTS", http.StatusConflict)
-	PermissionDenied   ErrorCodeName = E("PERMISSION_DENIED", http.StatusForbidden)
-	Unauthenticated    ErrorCodeName = E("UNAUTHENTICATED", http.StatusUnauthorized)
-	ResourceExhausted  ErrorCodeName = E("RESOURCE_EXHAUSTED", http.StatusTooManyRequests)
-	FailedPrecondition ErrorCodeName = E("FAILED_PRECONDITION", http.StatusBadRequest)
-	Aborted            ErrorCodeName = E("ABORTED", http.StatusConflict)
-	OutOfRange         ErrorCodeName = E("OUT_OF_RANGE", http.StatusBadRequest)
-	Unimplemented      ErrorCodeName = E("UNIMPLEMENTED", http.StatusNotImplemented)
-	Internal           ErrorCodeName = E("INTERNAL", http.StatusInternalServerError)
-	Unavailable        ErrorCodeName = E("UNAVAILABLE", http.StatusServiceUnavailable)
-	DataLoss           ErrorCodeName = E("DATA_LOSS", http.StatusInternalServerError)
+	Cancelled          ErrorCodeName = Register("CANCELLED", context.StatusTokenRequired)
+	Unknown            ErrorCodeName = Register("UNKNOWN", http.StatusInternalServerError)
+	InvalidArgument    ErrorCodeName = Register("INVALID_ARGUMENT", http.StatusBadRequest)
+	DeadlineExceeded   ErrorCodeName = Register("DEADLINE_EXCEEDED", http.StatusGatewayTimeout)
+	NotFound           ErrorCodeName = Register("NOT_FOUND", http.StatusNotFound)
+	AlreadyExists      ErrorCodeName = Register("ALREADY_EXISTS", http.StatusConflict)
+	PermissionDenied   ErrorCodeName = Register("PERMISSION_DENIED", http.StatusForbidden)
+	Unauthenticated    ErrorCodeName = Register("UNAUTHENTICATED", http.StatusUnauthorized)
+	ResourceExhausted  ErrorCodeName = Register("RESOURCE_EXHAUSTED", http.StatusTooManyRequests)
+	FailedPrecondition ErrorCodeName = Register("FAILED_PRECONDITION", http.StatusBadRequest)
+	Aborted            ErrorCodeName = Register("ABORTED", http.StatusConflict)
+	OutOfRange         ErrorCodeName = Register("OUT_OF_RANGE", http.StatusBadRequest)
+	Unimplemented      ErrorCodeName = Register("UNIMPLEMENTED", http.StatusNotImplemented)
+	Internal           ErrorCodeName = Register("INTERNAL", http.StatusInternalServerError)
+	Unavailable        ErrorCodeName = Register("UNAVAILABLE", http.StatusServiceUnavailable)
+	DataLoss           ErrorCodeName = Register("DATA_LOSS", http.StatusInternalServerError)
 )
 
 // errorFuncCodeMap is a read-only map of error code names and their error functions.
@@ -352,7 +355,7 @@ var (
 	// The server fails to send an error on two cases:
 	// 1. when the provided error code name is not registered (the error value is the ErrUnexpectedErrorCode)
 	// 2. when the error contains data but cannot be encoded to json (the value of the error is the result error of json.Marshal).
-	ErrUnexpected = E("UNEXPECTED_ERROR", http.StatusInternalServerError)
+	ErrUnexpected = Register("UNEXPECTED_ERROR", http.StatusInternalServerError)
 	// ErrUnexpectedErrorCode is the error which logged
 	// when the given error code name is not registered.
 	ErrUnexpectedErrorCode = New("unexpected error code name")