IDF Docker image (``espressif/idf``) is intended for building applications and libraries with specific versions of ESP-IDF, when doing automated builds.
- A copy of a specific version of ESP-IDF (see below for information about versions). ``IDF_PATH`` environment variable is set, and points to ESP-IDF location in the container.
- All Python packages required by ESP-IDF are installed in a virtual environment.
The image entrypoint sets up ``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 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 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
-``espressif/idf``: uses Docker image ``espressif/idf`` with tag ``latest`` (implicitly added by Docker when no tag is specified)
-``idf.py build``: runs this command inside the container
Commands which communicate with the development board, such as ``idf.py flash`` and ``idf.py monitor`` will 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 how to do this can be found in the following `using remote serial port`_ section.
.._using remote serial port:
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 esptool 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 how to use the flash command from within a Docker container.
On host start ``esp_rfc2217_server``. It 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 esptool utilities::
esp_rfc2217_server -v -p 4000 COM3
Now the device attached to the host can be flashed from inside a Docker container by using::
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 host IP if necessary.
The Dockerfile 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. Default is ``https://github.com/espressif/esp-idf.git``.
-``IDF_CLONE_BRANCH_OR_TAG``: Name of a git branch or tag use when cloning ESP-IDF. This value is passed to ``git clone`` command using the ``--branch`` argument. Default is ``master``.
-``IDF_CHECKOUT_REF``: If this argument is set to a non-empty value, ``git checkout $IDF_CHECKOUT_REF`` command will be performed 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 will be used when performing ``git clone``. This 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_INSTALL_TARGETS``: Comma-separated list of 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. Default is ``all``.
To use these arguments, pass them via the ``--build-arg`` command line option. For example, the following command will build a Docker image with a shallow clone of ESP-IDF v4.4.1 and tools for ESP32-C3, only::
