Reusable components for the ESP32

This repository demonstrates a simple setup that allows to develop multiple components that can be used in multiple applications.

Preconditions

• SDK ESP-IDF is cloned into a local folder
• Envrionment variable IDF_PATH has been set to the SDK location

Setup

The repository consists of the custom components and an application that uses it.

Custom components

They are located in the custom-components folder. The components itself are located in the components subdirectory. This example contains the awesome_compontent and contains a simple method that adds two numbers.

Structure of a component

A component is a folder in custom-components/components every component should be located in this folder. See the awesome-component as an example.

my_component/
    include/
        my_code.h
    src/
        my_code.c
    test/
        component.mk
            COMPONENT_ADD_LDFLAGS = -Wl,--whole-archive -l$(COMPONENT_NAME) -Wl,--no-whole-archive
        test_my_code.c
    component.mk
        COMPONENT_ADD_INCLUDEDIRS := include
        COMPONENT_SRCDIRS := src

Execute custom component tests

This is based on unit-test-app. It consist of a standard Makefile, main/main.c and main/component.mk. There is usually no need to change anything here.

Before we can execute tests make sure to set environment variable EXTRA_COMPONENT_DIRS to "$IDF_PATH/tools/unit-test-app/components" this makes the unity framework available for the build system. Another option is to copy the unity component from this folder to your components folder.

Execute the tests

Open the shell and navigate to repository/custom-components and invoke make flash TEST_COMPONENTS='component_name1 other_component' monitor. This compiles everything, flashes it to your esp and starts monitoring once flashing is completed. The shell should display a menu of all available tests once bootstrapping is completed. More details see Testing

Example for this repository make flash TEST_COMPONENTS='awesome_component' monitor

Application

Of course we want to use our components in our applications. These applications can be located anywhere. This repository has its example application app located in the repository for demonstration purpose. This is a standard esp-idf application. Nothing special here.

Make custom components available

The build system does not know anything about your custom components right now. This can be changed similar to the way we made the unity component availabel.

To do that change the EXTRA_COMPONENT_DIRS to "$IDF_PATH/tools/unit-test-app/components repositoryPath/custom-components/components" make sure to replace repositoryPath to the location of your folder.

Example environment variables

export IDF_PATH="pathToSDK/"
export EXTRA_COMPONENT_DIRS="$IDF_PATH/tools/unit-test-app/components /pathToMyComponents/"