# Functions
GetRESTAgentByError returns a RESTAgent by the given error.
New creates a new WithCode error with the given AppErrCode and error message.
# Constants
12: database.
13: business logic.
13: business logic.
10: common.
11: model.
# Structs
SimpleRESTAgent is a simple internal implementation of RESTAgent interface.
WithCode implements interface error as a wrapper of an error with AppErrCode.
# Interfaces
RESTAgent handles HTTP status and user-facing message for the response if an error of a certain AppErrCode occurs during RESTful API request.
# Type aliases
AppErrCode defines the type of Application error code Application error codes are made of 4 digits.