Web Sockets

there are 2

• terminal websocket used to stream data to webUI and exchange internal data

• data websocket used to exchange data with external client (not used by WebUI)

Terminal websocket

use subprotocol webui-v3 and port is same as web port but use address /ws

text mode

Reserved messages between webui / ESP Format: <label>:<message>

• from ESP to WebUI

  • currentID:<id> Sent when client is connecting, it is the last ID used and become the active ID

  • activeID:<id> Broadcast current active ID, when new client is connecting, client without this is should close, ESP WS Server close all open WS connections but this one also

  • PING:<time left>:<time out> It is a response to PING from client to inform the time left if no activity (see below)

  • ERROR:<code>:<message> If an error raise when doing upload, it informs client it must stop uploading because sometimes the http answer is not possible, or cannot cancel the upload, this is a workaround as there is no API in current webserver to cancel active upload

  • NOTIFICATION:<message> Forward the message sent by [ESP600] to webUI toast system

  • SENSOR: <value>[<unit>] <value2>[<unit2>] ... The sensor connected to ESP like DHT22

• from WebUI to ESP

  • PING:<current cookiesessionID / none > if any, or “none” if none

binary mode

Reserved

• from ESP to WebUI stream data from ESP to WebUI

• from WEBUI to ESP
  [-> File transfert from WebUI to ESP : not implemented yet]

Data websocket

use sub protocol arduino and port same as web port but use address /wsdata

text mode

This mode is used to transfert all GCODE commands and their answers from printer/cnc

binary mode

This mode is used to transfert files to / from esp board

it use frame of 1024 bytes, can be increased after test

the frame format is : 2 bytes: for frame type 2 bytes: for frame size to check some integrity, currently as already part of frame no checksume is used x bytes : extra data according frame type

Frame types

Query status frame

type: client -> esp Status Request

with hexadecimal values:

Response frame use inverted header: Response Status

with hexadecimal values:

the first byte of answer is the state

extra data may be added :

For Error:

error code and string, 1 byte : error code: 0->255 1 byte : string size 0->255 XX bytes for the string

For Upload:

Upload informations: 1 byte : path size 0->255 XX bytes : the path string 1 byte : the filename size 0->255 xx bytes : filename string 4 bytes : total file size 4 bytes : currently processed bytes 4 bytes : last packet id processed

For Download:

Download informations: 1 byte : path size 0->255 XX bytes : the path string 1 byte : the filename size 0->255 xx bytes : filename string 4 bytes : total file size 4 bytes : currently processed bytes 4 bytes : last packet id processed

Start upload frame

header is :

the content is: 1 byte : path size 0->255 XX bytes : the path string 1 byte : the filename size 0->255 xx bytes : filename string 4 bytes : total file size

if answer is :

it means transfert can start

Transfert upload frame

header is :

4 bytes is packet id XXXX bytes is data

if packet is received the answer is

Start dowload frame

header is :

the content is: 1 byte : path size 0->255 XX bytes : the path string 1 byte : the filename size 0->255 xx bytes : filename string 4 bytes : total file size

if answer is :

it means transfert can start

Transfert download frame

header is :

4 bytes is packet id XXXX bytes is data

if packet is received the answer is

Command frame

header is :

Commands:

Abort command frame