Note about Redis protocol specification

Nov 29 2017

This is the note that I create when reading about Redis protocol specification (RESP).

Networking Layer

RESP uses TCP, with request-response style.

Has 5 types: Simple String, Errors, Integer, Bulk Strings and Array
Every data end with "\r\n"
Simple String starts with a “+”. The string include “\r\n”. Client will return the string.
Error starts with a “-“. Convention “- ”. Client will raise and error.
Integer starts with a “:”. Integer will be a signed 64-bit integer.
Bulk Strings: starts with a “$”, followed by the string length, terminated by “\r\n”, followed by the actual string. The string is at most 512MB. Null String is “$-1\r\n”.
Array: starts with a “*”, followed by the number of elements and “\r\n”, followed by the Type for each element. Array can contain mixed types. There is also Null Array “*-1\r\r”