PicoWebsocket

PicoWebsocket is a websocket library for ESP8266 and ESP32 devices offering a seamless and intuitive interface, enabling effortless integration with any Arduino framework sockets.

PicoWebsocket let's you easily:

• Create client WebSockets on top of any Arduino client class, e.g. WiFiClient, EthernetClient or WiFiClientSecure.
• Create WebSocket servers on top of any Arduino server class, e.g. WiFiServer, EthernetServer or WiFiServerSecure.
• Use websocket server and client instances just like the raw underlying classes providing the same interface.

Quickstart

To get started, try compiling and running the code below or explore examples.

Client

#include <Arduino.h>
#include <ESP8266WiFi.h>        // use <WiFi.h> on the ESP32

#include <PicoWebsocket.h>

// Define the client -- any Arduino Client subclass can be
// used here (e.g. EthernetClient)
WiFiClient client;

// Define the websocket
PicoWebsocket::Client websocket(client);

void setup() {
    Serial.begin(115200);
    WiFi.begin("network", "secret");
}

void loop() {
    // Now we can use websocket just like we would use client.  Internally
    // data is exchanged using the websocket protocol, but we can ignore
    // that -- we'll only have to deal with payload data, as if it was
    // exchanged over a raw TCP connection.

    if (!websocket.connect("ws.vi-server.org", 80)) {
        // connection failed
        return;
    } // else: we're connected 

    // say hello
    websocket.println("Hello from PicoWebsocket!");

    // wait for reply
    while (websocket.connected() && !websocket.available()) {
        yield();
    }

    // read reply to buffer
    uint8_t buffer[128];
    const auto bytes_read = websocket.read(buffer, 128);
    Serial.write(buffer, bytes_read);
}

Server

#include <Arduino.h>
#include <ESP8266WiFi.h>        // use <WiFi.h> on the ESP32
#include <WiFiServer.h>

#include <PicoWebsocket.h>

// Define underlying server.  Any class that has a begin() and an accept()
// method will can be used here (e.g. EthernetServer)
WiFiServer server(80);

// Define a websocket server, which wraps server
PicoWebsocket::Server<WiFiServer> websocket_server(server);

void setup() {
    Serial.begin(115200);
    WiFi.begin("network", "secret");
    websocket_server.begin();
}

void loop() {
    // Now we can use websocket server just like we would use server.  Client
    // connections will be transparently upgraded to a websocket connection.
    // We'll only have to deal with payload data, as if it was exchanged over
    // a raw TCP connection.

    auto websocket = websocket_server.accept();
    if (!websocket) {
        // no client
        return;
    }

    // wait for a message
    while (websocket.connected() && !websocket.available()) {
        yield();
    }

    // read the message to a buffer and print it
    uint8_t buffer[128];
    const auto bytes_read = websocket.read(buffer, 128);
    Serial.write(buffer, bytes_read);

    // echo the message
    websocket.write(buffer, bytes_read);
}

Related projects

PicoWebsockets is used by the PicoMQTT library to implement MQTT over websockets.

License

This library is open-source software licensed under GNU LGPLv3.