Configurable firmware for IoT switch based on ESP8266 chip (and maybe ESP32). Using Espressif SDK and MQTT protocol for messaging.

• Prepare toolchain following the official guide - https://docs.espressif.com/projects/esp8266-rtos-sdk/en/latest/get-started/linux-setup.html
• Cd to project dir
• Run make all
• Plug in your ESP chip to serial port and flash make flash
• Run make monitor (turn off/on) to watch live log

• To put switch to configuration mode - quick turn off/on chip 3+ times. You should see slowly blinking builtin LED for 1 sec every second.
• Discover WiFi. Find 'esp-XXXXXX' access point and connect with password esp_admin (/main/app_wifi.h APP_WIFI_DEFAULT_AP_PASS)
• To request current WiFi config:

curl -X GET http://192.168.4.1/api/wifi/config

• To update WiFi config. Example:

curl -X POST http://192.168.4.1/api/wifi/config --data '{"ssid": "yourssid", "password": "yourpass"}'

• To request current MQTT config:

curl -X GET http://192.168.4.1/api/mqtt/config

• To update MQTT config. Example:

curl -X POST http://192.168.4.1/api/mqtt/config --data '{"uri": "mqtt://your.mqtt.host",  "username": "mqtt", "password": "yourpass",  "topic_forceon": {"path": "home/ups/state/onbattery"}}'

• Restart:

curl -X POST http://192.168.4.1/api/restart

Discover api endpoints & sources for more details here: /main/app_api*.c