esp-idf/examples/protocols/https_server/wss_server

HTTP Websocket server with SSL support

This example creates a SSL server and employs a simple Websocket request handler. It demonstrates handling multiple clients from the server including:

• PING-PONG mechanism
• Sending asynchronous messages to all clients

See the esp_https_server component documentation for details.

Before using the example, open the project configuration menu (idf.py menuconfig) to configure Wi-Fi or Ethernet. See "Establishing Wi-Fi or Ethernet Connection" section in examples/protocols/README.md for more details.

httpd_ws_recv_frame support two ways to get frame payload.

• Static buffer -- Allocate maximum expected packet length (either statically or dynamically) and call httpd_ws_recv_frame() referencing this buffer and it's size. (Unnecessarily large buffers might cause memory waste)

#define MAX_PAYLOAD_LEN 128
uint8_t buf[MAX_PAYLOAD_LEN] = { 0 };
httpd_ws_frame_t ws_pkt;
ws_pkt.payload = buf;
httpd_ws_recv_frame(req, &ws_pkt, MAX_PAYLOAD_LEN);

• Dynamic buffer -- Refer to the examples, which receive websocket data in these three steps:
  1. Call httpd_ws_recv_frame() with zero buffer size
  2. Allocate the size based on the received packet length
  3. Call httpd_ws_recv_frame() with the allocated buffer

Certificates

You will need to approve a security exception in your browser. This is because of a self signed certificate; this will be always the case, unless you preload the CA root into your browser/system as trusted.

You can generate a new certificate using the OpenSSL command line tool:

openssl req -newkey rsa:2048 -nodes -keyout prvtkey.pem -x509 -days 3650 -out cacert.pem -subj "/CN=ESP32 HTTPS server example"

Expiry time and metadata fields can be adjusted in the invocation.

Please see the openssl man pages (man openssl-req) for more details.

It is strongly recommended to not reuse the example certificate in your application; it is included only for demonstration.