3.3. Network Protocol

The interaction between a client and a server is a simple iterative dialog where the client sends a query, and waits for an answer from the server.

All values are sent as 64-bit little-endian numbers.

3.3.1. Client to Server

Prefix	Data	Description
joedb	client_version	first message, sent at connection time
H	until hash (32 bytes)	check SHA-256 hash code (fast)
I	until hash (32 bytes)	check SHA-256 hash code (full)
r	from until	read a range of bytes
D	wait from	pull, no lock, no data
E	wait from	pull, lock, no data
F	wait from	pull, no lock, data
G	wait from	pull, lock, data
L		lock
M		unlock
N	from until data	push, keep locked
O	from until data	push, unlock

Prefix	Data	Description
joedb	server_version session_id checkpoint ‘R’ or ‘W’	reply to joedb. server_version = 0 means client_version is rejected. ‘R’ is pull-only
H		reply to H, hash is matching
I		reply to I, hash is matching
h		reply to H or I, hash mismatch
r	until data	reply to r (size may be shorter than what was asked)
D	until	reply to D
E	until	reply to E
F	until data	reply to F
G	until data	reply to G
L		reply to L
M		reply to M
N		reply to N
O		reply to O
R		reply to E, G, L, M, N, O when the server is read-only
C		reply to N, O in case of conflict
t		reply to N, O in case of time out