micropython-lib/README.md

# micropython-lib

This is a repository of packages designed to be useful for writing MicroPython
applications.

The packages here fall into categories corresponding to the four top-level
directories:

* **python-stdlib**: Compatible versions of modules from [The Python Standard
    Library](https://docs.python.org/3/library/). These should be drop-in
    replacements for the corresponding Python modules, although many have
    reduced functionality or missing methods or classes (which may not be an
    issue for most cases).

 * **python-ecosys**: Compatible, but reduced-functionality versions of
     packages from the wider Python ecosystem. For example, a package that
     might be found in the [Python Package Index](https://pypi.org/).

 * **micropython**: MicroPython-specific packages that do not have equivalents
     in other Python environments. This includes drivers for hardware
     (e.g. sensors, peripherals, or displays), libraries to work with
     embedded functionality (e.g. bluetooth), or MicroPython-specific
     packages that do not have equivalents in CPython.

* **unix-ffi**: These packages are specifically for the MicroPython Unix port
    and provide access to operating-system and third-party libraries via FFI,
    or functionality that is not useful for non-Unix ports.

## Usage

To install a micropython-lib package, there are four main options. For more
information see the [Package management documentation](https://docs.micropython.org/en/latest/reference/packages.html)
documentation.

### On a network-enabled device

As of MicroPython v1.20 (and nightly builds since October 2022), boards
with WiFi and Ethernet support include the `mip` package manager.

```py
>>> import mip
>>> mip.install("package-name")
```

### Using `mpremote` from your PC

`mpremote` is the officially-supported tool for interacting with a MicroPython
device and, since v0.4.0, support for installing micropython-lib packages is
provided by using the `mip` command.

```bash
$ mpremote connect /dev/ttyUSB0 mip install package-name
```

See the [mpremote documentation](https://docs.micropython.org/en/latest/reference/mpremote.html).

### Freeze into your firmware

If you are building your own firmware, all packages in this repository include
a `manifest.py` that can be included into your board manifest via the
`require()` command. See [Manifest files](https://docs.micropython.org/en/latest/reference/manifest.html#require) for
more information.

### Copy the files manually

Many micropython-lib packages are just single-file modules, and you can
quickly get started by copying the relevant Python file to your device. For
example, to add the `base64` library, you can directly copy
`python-stdlib/base64/base64.py` to the `lib` directory on your device.

This can be done using `mpremote`, for example:

```bash
$ mpremote connect /dev/ttyUSB0 cp python-stdlib/base64/base64.py :/lib
```

For packages that are implemented as a package directory, you'll need to copy
the directory instead. For example, to add `collections.defaultdict`, copy
`collections/collections/__init__.py` and
`collections-defaultdict/collections/defaultdict.py` to a directory named
`lib/collections` on your device.

Note that unlike the other three approaches based on `mip` or `manifest.py`,
you will need to manually resolve dependencies. You can inspect the relevant
`manifest.py` file to view the list of dependencies for a given package.

## Installing packages from forks

It is possible to use the `mpremote mip install` or `mip.install()` methods to
install packages built from a
[fork](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/about-forks)
of micropython-lib, if the fork's owner has opted in.

This can be useful to install packages from a pending Pull Request, for example.

First, the owner of the fork must opt-in as described under
[Publishing packages from forks](CONTRIBUTING.md#publishing-packages-from-forks).

After this has happened, each time someone pushes to a branch in that fork then
GitHub Actions will automatically publish the packages to a GitHub Pages site.

To install these packages, use commands such as:

```bash
$ mpremote connect /dev/ttyUSB0 mip install --index https://USERNAME.github.io/micropython-lib/mip/BRANCH_NAME PACKAGE_NAME
```

Or from a networked device:

```py
import mip
mip.install(PACKAGE_NAME, index="https://USERNAME.github.io/micropython-lib/mip/BRANCH_NAME")
```

(Where `USERNAME`, `BRANCH_NAME` and `PACKAGE_NAME` are replaced with the owner
of the fork, the branch the packages were built from, and the package name.)

## Contributing

We use [GitHub Discussions](https://github.com/micropython/micropython/discussions)
as our forum, and [Discord](https://micropython.org/discord) for chat. These
are great places to ask questions and advice from the community or to discuss your
MicroPython-based projects.

The [MicroPython Wiki](https://github.com/micropython/micropython/wiki) is
also used for micropython-lib.

For bugs and feature requests, please [raise an issue](https://github.com/micropython/micropython-lib/issues/new).

We welcome pull requests to add new packages, fix bugs, or add features.
Please be sure to follow the
[Contributor's Guidelines & Code Conventions](CONTRIBUTING.md). Note that
MicroPython is licensed under the [MIT license](LICENSE) and all contributions
should follow this license.

### Future plans (and new contributor ideas)

* Develop a set of example programs using these packages.
* Develop more MicroPython packages for common tasks.
* Expand unit testing coverage.
* Add support for referencing remote/third-party repositories.

## Notes on terminology

The terms *library*, *package*, and *module* are overloaded and lead to some
confusion. The interpretation used in by the MicroPython project is that:

A *library* is a collection of installable packages, e.g. [The Python Standard
  Library](https://docs.python.org/3/library/), or micropython-lib.

A *package* can refer to two things. The first meaning, "library package", is
something that can be installed from a library, e.g. via `mip` (or `pip` in
CPython/PyPI). Packages provide *modules* that can be imported. The ambiguity
here is that the module provided by the package does not necessarily have to
have the same name, e.g. the `pyjwt` package provides the `jwt` module. In
CPython, the `pyserial` package providing the `serial` module is another
common example.

A *module* is something that can be imported. For example, "the *os* module".

A module can be implemented either as a single file, typically also called
a *module* or "single-file module", or as a *package* (the second meaning),
which in this context means a directory containing multiple `.py` files
(usually at least an `__init__.py`).

In micropython-lib, we also have the concept of an *extension package* which
is a library package that extends the functionality of another package, by
adding additional files to the same package directory. These packages have
hyphenated names. For example, the `collections-defaultdict` package extends
the `collections` package to add the `defaultdict` class to the `collections`
module.