tl;dr;

As a new user of esp32-ble2mqtt, the toolchain required to build it seemed non-obvious to me. These are my notes on how to get going with it.

Installing dependencies

You should clone this repo with git clone --recursive path_to_repo to pull in matched versions of esp-idf and esp32-ble2mqtt. If you didn't do this and already have a checked out copy, git submodule update --init --recursive will do it.

ESP-IDF dependencies

This bit follows https://docs.espressif.com/projects/esp-idf/en/stable/get-started/linux-setup.html

wget https://dl.espressif.com/dl/xtensa-esp32-elf-linux64-1.22.0-80-g6c4433a-5.2.0.tar.gz
mkdir esp
cd esp
tar xvf xtensa-esp32-elf-linux64-1.22.0-80-g6c4433a-5.2.0.tar.gz

sudo apt-get install gcc git wget make libncurses-dev flex bison gperf
virtualenv -p python2 esp-venv
. esp-venv/bin/activate
pip install -r esp-idf/requirements.txt

Building

export PATH="/full/path/to/xtensa-esp32-elf/bin:$PATH"
cd esp32-ble2mqtt
export IDF_PATH=../esp-idf
make

First run with do make menuconfig in esp-idf. Set Serial flasher config to /dev/ttyUSB0 or wherever your ESP32 is connected and Save.

You might get errors about __bswap16() not being a function. Change it to __bswap_16() if you do.

Installing

make flash