2.4 KiB
2.4 KiB
This document describes the expected usage of the library. It mixes go code and prose to expose what is intended. Also it features expected behavior and some library rules and websocket standards (e.g. RFC).
Warning
This document is not a documentation, it is used by developers to try to find the best interface for an eased usage by other developers using this library.
Handshake
1. Client HTTP Upgrade Request
This request is sent by clients which want to open a new websocket connection.
GET {uri} HTTP/{httpClientVersion}
Host: {host}
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Key: {clientKey}
Origin: {origin}
Sec-WebSocket-Protocol: {clientProtocols[]}
Sec-WebSocket-Extensions: {clientExtensions[]}
Sec-WebSocket-Version: {wsVersion}
Required fields
httpClientVersion
at least 1.1host
...Upgrade: websocket
header (not case sensitive)Connection: Upgrade
header (not case sensitive)Origin
for security issues only when from browser (to study)clientKey
because it is not consistent websocket without it. It must be a 16-byte value base64 encodedwsVersion
is required to be 13
Optional fields
clientProtocols[]
if not received is an empty listclientExtensions[]
if not received is an empty list
2. Server HTTP Response
HTTP/{httpServerVersion} {errorCode} Switching Protocols
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Accept: {serverKey}
Sec-WebSocket-Protocol: {serverProtocol}
Required fields
Upgrade: websocket
header because RFCConnection: Upgrade
header because RFCerrorCode
is 101 on success, other on failure- 400 Bad Request on missing or malformed headers
- 403 Forbidde on invalid
Origin
orhttps
/wss
required, ... - 426 Upgrade Required on invalid
wsVersion
- 404 Not Found on unserved or invalid
uri
- 1002 Protocol Error if received a non-masked frame
serverKey
but can be invalid if server don't want to accept the connection
Optional fields
serverProtocol
if the server has chosen one
Clients management
- It is required that for a same
host
andport
pair, a client can only have one connection in aCONNECTING
state. It means that one client can open a 2nd connection only when the 1st succeeded or failed.
Frames
- RFC requires the server to close all connections which sends a non-masked frame