ConvertFromMap uses json to marshal and unmarshal a map into a target type.

ConvertToMap uses json to marshal and unmarshal a target type into a map.

DeepCopy creates a deep copy/clone of a struct by using json to marshal the original struct, and then unmarshal it back into the new copy.

MergeMaps combines the src map keys and values with the dest map keys and values if the key exists.

MergeValues combines src with the dest.

SendJsonErrResp puts together the error response packet for the APIs.

SendJsonResp puts together the response packet for the APIs.

WrapHandler wraps `handler func(http.ResponseWriter, *http.Request)` into `echo.HandlerFunc`.