OVMS3-idf/docs/en/api-reference/protocols/esp_websocket_client.rst

71 lines
1.8 KiB
ReStructuredText
Raw Normal View History

ESP WebSocket Client
====================
Overview
--------
The ESP WebSocket client is an implementation of `WebSocket protocol client <https://tools.ietf.org/html/rfc6455>`_ for ESP32
Features
--------
* supports WebSocket over TCP, SSL with mbedtls
* Easy to setup with URI
* Multiple instances (Multiple clients in one application)
Configuration
-------------
URI
^^^
- Supports ``ws``, ``wss`` schemes
- WebSocket samples:
- ``ws://websocket.org``: WebSocket over TCP, default port 80
- ``wss://websocket.org``: WebSocket over SSL, default port 443
- Minimal configurations:
.. code:: c
const esp_websocket_client_config_t ws_cfg = {
.uri = "ws://websocket.org",
};
- If there are any options related to the URI in
``esp_websocket_client_config_t``, the option defined by the URI will be
overridden. Sample:
.. code:: c
const esp_websocket_client_config_t ws_cfg = {
.uri = "ws://websocket.org:123",
.port = 4567,
};
//WebSocket client will connect to websocket.org using port 4567
SSL
^^^
- Get certificate from server, example: ``websocket.org``
``openssl s_client -showcerts -connect websocket.org:443 </dev/null 2>/dev/null|openssl x509 -outform PEM >websocket_org.pem``
- Configuration:
.. code:: cpp
const esp_websocket_client_config_t ws_cfg = {
.uri = "wss://websocket.org",
.cert_pem = (const char *)websocket_org_pem_start,
};
For more options on ``esp_websocket_client_config_t``, please refer to API reference below
Application Example
-------------------
Simple WebSocket example that uses esp_websocket_client to establish a websocket connection and send/receive data with the `websocket.org <https://websocket.org>`_ Server: :example:`protocols/websocket`.
API Reference
-------------
.. include-build-file:: inc/esp_websocket_client.inc