Writing a REST Service with Cloud Pages - GET Method

%%[
var @action,@entrycode,@Json,@JsonNotFound,@EmailAddress,@FristName,@LastName,@phone,@rowCount,@row,@rows

set @action=Requestparameter("action")
set @entrycode=Requestparameter("entrycode")
set @JsonNotFound=' {"status": "error","message": "Could not find record with entrycode" }'

If @action=="get" and not empty (@entrycode) then
	set @rows = LookupRows("Register","EntryCode",@entrycode)
	set @rowCount = rowcount(@rows)
	
If@rowCount==0 then
		output(v(@JsonNotFound))
	endif
	
	If @rowCount > 0 then		
set @row = row(@rows,1) 
		set @EmailAddress = field(@row,"EmailAddress")
		set @FristName = field(@row,"FirstName")
		set @LastName = field(@row,"LastName")
		set @phone = field(@row,"PhoneNumber")
		set @Json= '{"status": "ok","data": {"EntryCode":"'
		set @Json= concat(@Json,@entrycode,'","email": "',@EmailAddress)
		set @Json= concat(@Json,'","firstName":"',@FristName)
		set @Json= concat(@Json,'","lastName":"',@LastName)
		set @Json= concat(@Json,'","phoneNumber":"',@phone,'"}')
		set @Json= concat(@Json,'}')
		output(v(@Json))
	endif	
endif
]%%