IDF Docker Image

IDF Docker image (espressif/idf) is intended for building applications and libraries with specific versions of ESP-IDF when doing automated builds.

The image contains:

• Common utilities such as git, wget, curl, and zip.

• Python 3.8 or newer.

• A copy of a specific version of ESP-IDF. See below for information about versions. IDF_PATH environment variable is set and points to the ESP-IDF location in the container.

• All the build tools required for the specific version of ESP-IDF: CMake, Ninja, cross-compiler toolchains, etc.

• All Python packages required by ESP-IDF are installed in a virtual environment.

The image ENTRYPOINT sets up the PATH environment variable to point to the correct version of tools, and activates the Python virtual environment. As a result, the environment is ready to use the ESP-IDF build system.

The image can also be used as a base for custom images, if additional utilities are required.

Tags

Multiple tags of this image are maintained:

• latest: tracks master branch of ESP-IDF

• vX.Y: corresponds to ESP-IDF release vX.Y

• release-vX.Y: tracks release/vX.Y branch of ESP-IDF

Note

Versions of ESP-IDF released before this feature was introduced do not have corresponding Docker image versions. You can check the up-to-date list of available tags at https://hub.docker.com/r/espressif/idf/tags.

Usage

Setting up Docker

Before using the espressif/idf Docker image locally, make sure you have Docker installed. Follow the instructions at https://docs.docker.com/install/, if it is not installed yet.

If using the image in a CI environment, consult the documentation of your CI service on how to specify the image used for the build process.

Building a Project with CMake

In the project directory, run:

docker run --rm -v $PWD:/project -w /project -u $UID -e HOME=/tmp espressif/idf idf.py build

The above command explained:

• docker run: runs a Docker image. It is a shorter form of the command docker container run.

• --rm: removes the container when the build is finished.

• -v $PWD:/project: mounts the current directory on the host ($PWD) as /project directory in the container.

• -w /project: makes /project the working directory for the command.

• -u $UID: makes the command run with your user ID so that files are created as you (instead of root).

• -e HOME=/tmp: gives the user a home directory for storing temporary files created by idf.py in ~/.cache.

• espressif/idf: uses Docker image espressif/idf with tag latest. The latest tag is implicitly added by Docker when no tag is specified.

• idf.py build: runs this command inside the container.

Note

When the mounted directory, /project, contains a git repository owned by a different user (UID) than the one running the Docker container, git commands executed within /project might fail, displaying an error message fatal: detected dubious ownership in repository at '/project'. To resolve this issue, you can designate the /project directory as safe by setting the IDF_GIT_SAFE_DIR environment variable during the Docker container startup. For instance, you can achieve this by including -e IDF_GIT_SAFE_DIR='/project' as a parameter. Additionally, multiple directories can be specified by using a : separator. To entirely disable this git security check, * can be used.

To build with a specific Docker image tag, specify it as espressif/idf:TAG, for example:

docker run --rm -v $PWD:/project -w /project -u $UID -e HOME=/tmp espressif/idf:release-v4.4 idf.py build

You can check the up-to-date list of available tags at https://hub.docker.com/r/espressif/idf/tags.

Using the Image Interactively

It is also possible to do builds interactively, to debug build issues or test the automated build scripts. Start the container with -i -t flags:

docker run --rm -v $PWD:/project -w /project -u $UID -e HOME=/tmp -it espressif/idf

Then inside the container, use idf.py as usual:

idf.py menuconfig
idf.py build

Note

Commands which communicate with the development board, such as idf.py flash and idf.py monitor does not work in the container, unless the serial port is passed through into the container. This can be done with Docker for Linux with the device option. However, currently, this is not possible with Docker for Windows (\<https://github.com/docker/for-win/issues/1018\>) and Docker for Mac (\<https://github.com/docker/for-mac/issues/900\>). This limitation may be overcome by using remote serial ports. An example of how to do this can be found in the following using remote serial port section.

Using Remote Serial Port

The RFC2217 (Telnet) protocol can be used to remotely connect to a serial port. For more information please see the remote serial ports documentation in the ESP tool project. This method can also be used to access the serial port inside a Docker container if it cannot be accessed directly. Following is an example of how to use the Flash command from within a Docker container.

On host install and start esp_rfc2217_server:

• On Windows, the package is available as a one-file bundled executable created by pyinstaller and it can be downloaded from the esptool releases page in a ZIP archive along with other ESP tool utilities:

  esp_rfc2217_server -v -p 4000 COM3

• On Linux or macOS, the package is available as part of esptool, which can be found in the ESP-IDF environment or by installing using pip:

  pip install esptool

And then starting the server by executing

esp_rfc2217_server.py -v -p 4000 /dev/ttyUSB0

Now the device attached to the host can be flashed from inside a Docker container by using:

docker run --rm -v <host_path>:/<container_path> -w /<container_path> espressif/idf idf.py --port 'rfc2217://host.docker.internal:4000?ign_set_control' flash

Please make sure that <host_path> is properly set to your project path on the host, and <container_path> is set as a working directory inside the container with the -w option. The host.docker.internal is a special Docker DNS name to access the host. This can be replaced with a host IP if necessary.

Building Custom Images

The Docker file in ESP-IDF repository provides several build arguments which can be used to customize the Docker image:

• IDF_CLONE_URL: URL of the repository to clone ESP-IDF from. Can be set to a custom URL when working with a fork of ESP-IDF. The default is https://github.com/espressif/esp-idf.git.

• IDF_CLONE_BRANCH_OR_TAG: Name of a git branch or tag used when cloning ESP-IDF. This value is passed to the git clone command using the --branch argument. The default is master.

• IDF_CHECKOUT_REF: If this argument is set to a non-empty value, git checkout $IDF_CHECKOUT_REF command performs after cloning. This argument can be set to the SHA of the specific commit to check out, for example, if some specific commit on a release branch is desired.

• IDF_CLONE_SHALLOW: If this argument is set to a non-empty value, --depth=1 --shallow-submodules arguments are used when performing git clone. Depth can be customized using IDF_CLONE_SHALLOW_DEPTH. Doing a shallow clone significantly reduces the amount of data downloaded and the size of the resulting Docker image. However, if switching to a different branch in such a "shallow" repository is necessary, an additional git fetch origin <branch> command must be executed first.

• IDF_CLONE_SHALLOW_DEPTH: This argument specifies the depth value to use when doing a shallow clone. If not set, --depth=1 will be used. This argument has effect only if IDF_CLONE_SHALLOW is used. Use this argument if you are building a Docker image for a branch, and the image has to contain the latest tag on that branch. To determine the required depth, run git describe for the given branch and note the offset number. Increment it by 1, then use it as the value of this argument. The resulting image will contain the latest tag on the branch, and consequently git describe command inside the Docker image will work as expected.

• IDF_INSTALL_TARGETS: Comma-separated list of ESP-IDF targets to install toolchains for, or all to install toolchains for all targets. Selecting specific targets reduces the amount of data downloaded and the size of the resulting Docker image. The default is all.

To use these arguments, pass them via the --build-arg command line option. For example, the following command builds a Docker image with a shallow clone of ESP-IDF v4.4.1 and tools for ESP32-C3 only:

docker build -t idf-custom:v4.4.1-esp32c3 \
    --build-arg IDF_CLONE_BRANCH_OR_TAG=v4.4.1 \
    --build-arg IDF_CLONE_SHALLOW=1 \
    --build-arg IDF_INSTALL_TARGETS=esp32c3 \
    tools/docker