PlatformIO Bazel rules

These are Bazel Starlark rules for building and uploading Arduino programs using the PlatformIO build system.

Disclaimer

This is not an official Google product.

Prerequisites

These rules don't execute the compiler directly. Instead they copy the libraries into a directory structure compatible with the PlatformIO build system and then execute the build via PlatformIO.

In order to do this, the rules execute couple of commands which must already be present on the system. The following commands are required:

• /bin/cp
• /usr/bin/zip
• /usr/bin/unzip
• /usr/local/bin/platformio

The first three ar usually available on any linux system. The platformio command is added by installing PlatformIO.

Setup

In order to use these Bazel rules, you must add this git repository to your WORKSPACE file and load the platformio rule definition in every BUILD file where they are needed.

Modify the WORKSPACE file

See Releases for the most up to date version to substitute for tag.

load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
git_repository(
    name = "platformio_rules",
    remote = "http://github.com/mum4k/platformio_rules.git",
    tag = "v0.0.14",
)

load("@platformio_rules//bazel:deps.bzl", "platformio_rules_dependencies")
platformio_rules_dependencies()

load("@platformio_rules//bazel:transitive.bzl", "platformio_rules_transitive_dependencies")
platformio_rules_transitive_dependencies()

load("@platformio_rules//bazel:pip_parse.bzl", "platformio_rules_pip_parse_dependencies")
platformio_rules_pip_parse_dependencies()

load("@platformio_rules//bazel:pip_install.bzl", "platformio_rules_pip_install_dependencies")
platformio_rules_pip_install_dependencies()

Load the rule definitions in the BUILD file

To load the Starlark definitions in your BUILD file add the following at the top of the BUILD file.

load(
    "@platformio_rules//platformio:platformio.bzl",
    "platformio_library",
    "platformio_project",
)

Defined rules

The following rules are defined for PlatformIO:

• platformio_library
• platformio_project

See the generated documentation.

Rules documentation

These rules have standard Starlark documentation inside the platformio_docs directory.

To rebuild the documentation run:

bazel build docs:platformio_docs

And then copy the created markdown file:

cp $(bazel info bazel-bin)/docs/platformio_doc.md docs/

Examples

See the tests subdirectory for a working example.

Define a PlatformIO library

In the BUILD file:

platformio_library(
    name = "Convert",
    hdr = "convert.h",
    src = "convert.cc",
)

Define a PlatformIO project

In the BUILD file:

platformio_project(
    name = "binary_counter",
    src = "binary_counter.cc",
    board = "megaatmega2560",
    framework = "arduino",
    platform = "atmelavr",
    deps = [
        ":Convert",
    ],
    # If you need to you can pass multiple string key-value pairs directly
    # to PlatformIO. All of these will appear under the environment section in
    # the generated platformio.ini file. That would be "[env:megaatmega2560]" in
    # this example. For the available options see:
    # http://docs.platformio.org/en/stable/projectconf.html
    environment_kwargs = {
        "board_f_cpu": "16000000L",
    }
)

Building with the rules

To build the library defined above you would run:

bazel build :Convert

To build the project defined above you would run:

bazel build :binary_counter

Uploading with the rules

When you run the project, it will upload the compiled firmware to the connected Arduino device.

bazel run :binary_counter