sonotify-nfc-esp32

ESP32 firmware that reads a dispatch JSON (list of NFC tag -> Spotify URIs) and triggers a Home Assistant webhook to play a selected Spotify URI on a Sonos device.

This repository contains a simple example using:

• ESP-IDF
• SPIFFS (for storing dispatch.json)
• cJSON (JSON parsing)
• esp_http_client (downstream HTTP POST to Home Assistant webhook)
• Wi‑Fi connectivity

Repository layout

• main/sonotify-nfc-esp32.c — main application source.
• main/CMakeLists.txt, main/idf_component.yml, main/Kconfig.projbuild — component build metadata.
• data/dispatch.json — example JSON containing tag entries (copied into SPIFFS at deploy time).
• Other project files for build and configuration are present at the repo root.

Features / behavior

• Connects to Wi‑Fi using WIFI_SSID / WIFI_PASSWORD (provided via menuconfig).
• Initializes SPIFFS and reads /spiffs/dispatch.json.
• Selects the first entry and extracts spotifyUri.
• Performs an HTTP POST to a Home Assistant webhook URL with form fields uri and entity_id.

Configuration

• Wi‑Fi SSID and password are configured in menuconfig (main/Kconfig.projbuild):

  • WIFI_SSID
  • WIFI_PASSWORD

• Home Assistant webhook URL and Sonos entity ID are hardcoded in main/sonotify-nfc-esp32.c:

  • HA_WEBHOOK_URL
  • SONOS_ENTITY_ID

Adjust these defines in code or convert them into menuconfig options if you prefer runtime configuration.

Preparing SPIFFS

This project expects dispatch.json to be available under SPIFFS at /spiffs/dispatch.json. Typical workflow:

1. Keep your dispatch.json under data/dispatch.json (example provided).
2. Create a data partition or use ESP-IDF's spiffs partition tool to embed or flash the file to SPIFFS.

Refer to the ESP-IDF documentation for creating/packing SPIFFS data (component spiffs and partition_table usage).

Build & flash (quick)

1. Configure the project:

   • idf.py menuconfig
   • Set Wi‑Fi values under the "WiFi Configuration" menu

2. Build and flash:

   • idf.py build
   • idf.py -p /dev/ttyUSB0 flash monitor

Replace /dev/ttyUSB0 with your serial adapter device.

Troubleshooting

• If the device fails to mount SPIFFS, check partition table and that the SPIFFS partition exists.
• If the HTTP POST fails, verify the HA_WEBHOOK_URL and the device has network connectivity.
• Use the serial monitor (idf.py monitor) to view ESP_LOG output.

License

MIT License Copyright (c) 2026 André Santos