WebSocket Server and Client for Arduino

a WebSocket Server and Client for Arduino based on RFC6455.

Supported features of RFC6455

text frame
binary frame
connection close
ping
pong
continuation frame

Limitations

max input length is limited to the ram size and the WEBSOCKETS_MAX_DATA_SIZE define
max output length has no limit (the hardware is the limit)
Client send big frames with mask 0x00000000 (on AVR all frames)
continuation frame reassembly need to be handled in the application code

Limitations for Async

Functions called from within the context of the websocket event might not honor yield() and/or delay(). See this issue for more info and a potential workaround.
wss / SSL is not possible.

Supported Hardware

ESP8266 Arduino for ESP8266
ESP32 Arduino for ESP32
ESP31B
Particle with STM32 ARM Cortex M3
ATmega328 with Ethernet Shield (ATmega branch)
ATmega328 with enc28j60 (ATmega branch)
ATmega2560 with Ethernet Shield (ATmega branch)
ATmega2560 with enc28j60 (ATmega branch)

Note:

version 2.0.0 and up is not compatible with AVR/ATmega, check ATmega branch.

version 2.3.0 has API changes for the ESP8266 BareSSL (may brakes existing code)

Arduino for AVR not supports std namespace of c++.

wss / SSL

supported for:

wss client on the ESP8266
wss / SSL is not natively supported in WebSocketsServer however it is possible to achieve secure websockets by running the device behind an SSL proxy. See Nginx for a sample Nginx server configuration file to enable this.

ESP Async TCP

This libary can run in Async TCP mode on the ESP.

The mode can be activated in the WebSockets.h (see WEBSOCKETS_NETWORK_TYPE define).

ESPAsyncTCP libary is required.

High Level Client API

begin : Initiate connection sequence to the websocket host.

void begin(const char *host, uint16_t port, const char * url = "/", const char * protocol = "arduino");
void begin(String host, uint16_t port, String url = "/", String protocol = "arduino");

onEvent: Callback to handle for websocket events

void onEvent(WebSocketClientEvent cbEvent);

WebSocketClientEvent: Handler for websocket events

void (*WebSocketClientEvent)(WStype_t type, uint8_t * payload, size_t length)

Where WStype_t type is defined as:

typedef enum {
    WStype_ERROR,
    WStype_DISCONNECTED,
    WStype_CONNECTED,
    WStype_TEXT,
    WStype_BIN,
    WStype_FRAGMENT_TEXT_START,
    WStype_FRAGMENT_BIN_START,
    WStype_FRAGMENT,
    WStype_FRAGMENT_FIN,
    WStype_PING,
    WStype_PONG,
} WStype_t;

Issues

Submit issues to: https://github.com/Links2004/arduinoWebSockets/issues

License and credits

The library is licensed under LGPLv2.1

libb64 written by Chris Venter. It is distributed under Public Domain see LICENSE.