Add Firmata Integration (attempt 2)

[DaAwesomeP]

Proposed change

This pull adds a new Firmata integration.

• Binary digital input and output is implemented.
• Input is effectively done by push and callbacks instead of constantly telling the Arduino read inputs
• This still uses YAML and not config flows, but if I am understanding the mandate correctly then this falls into the category of OK to do that with since it is not a plug-and-play solution. It is also basically impossible to automatically discover how the user wants to configure each pin.
• This should deprecate the existing Arduino integration once I implement analog IO in a later pull. This one is async, uses push updates from the Arduino, and is more accurately named.

This is an updated continuation of an older pull (#24014).

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Example entry for configuration.yaml:

# Example configuration.yaml
firmata:
  - serial_port: /dev/serial/by-id/usb-Teensyduino_USB_Serial_358320-if00
    serial_baud_rate: 57600
    switches:
      - name: my_light
        pin_mode: OUTPUT
        pin: 4
        negate: true
      - name: my_other_output
        pin_mode: OUTPUT
        pin: 5
        negate: false
    binary_sensors:
      - name: stairs_motion
        pin_mode: PULLUP
        pin: 3

Additional information

• This PR is related to issue: Add Firmata Component #24014 is the original old pull
• Link to documentation pull request: Add Firmata integration docs home-assistant.io#13508

The usage of a Git repo for a requirement is temporary but should allow for at least a code review. I am awaiting a release on the Pymata side to fix some issues with event loop handling in the library (it required an empty loop and closes the loop on failure)—my pull was accepted and the developer is doing some testing.

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist (see additional info about Git requirement)
• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works. (this is a hardware integration without config flows, there are no tests) Tests have been added for the config flow

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

If the code communicates with devices, web services, or third-party tools:

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest. (see additional info about Git requirement)
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all. (see additional info about Git requirement)
• Untested files have been added to .coveragerc.

The integration reached or maintains the following Integration Quality Scale:

• No score or internal
• 🥈 Silver
• 🥇 Gold
• 🏆 Platinum

[DaAwesomeP]

I have fixed the Pymata dependency issue (the async issue in the Pypy version has been fixed). I have updated the checklist. I have started working on docs.

[DaAwesomeP]

I have opened a pull for docs and updated the above checklist.

[DaAwesomeP]

OK, I have been running the integration on my HA setup for a while now and I can successfully report zero issues!

[DaAwesomeP]

OK, I ran python3 -m script.scaffold config_flow, but this seemed to have generated an entire config flow. I do not want it to appear in the integrations add menu in the UI. I am not sure if I ran the right script. I see it added a test file though. Is that the only file I need?

I am also not sure what I am testing here. There is no pymata-mocks, so I am unsure how I would simulate the connection. Would you mind clarifying what exactly I need to add/change?

[DaAwesomeP]

If you have an example of what the tests and strings.json should look like for a YAML-only integration, that would be awesome.

[MartinHjelmare]

We want to test that each entry point and exit point in the config flow behaves as expected and generates the correct result.

In our case here that should be one test for successful entry creation and one test for unsuccessful connection with abort as result.

Patch the library to avoid I/O in the tests. Follow the example code generated by the scaffold script.

Search for other config flow tests that test the import step. It's basically the same as testing the user step, just a different step name so the source will be different.

[DaAwesomeP]

OK, so it also seems maybe I should be using the connection_error string since it is preferred as a builtin. However, this is an error instead of an abort., so my strings.json looks more like this:

{
    "config": {
        "error": {
            "cannot_connect": "[%key:common::config_flow::error::cannot_connect%]"
        },
        "step": {
            "import": {}
        }
    }
}

But I am confused how then to raise the error. Here is one example that confuses me:

async def async_step_import(self, user_input=None):
    """Handle the import."""
    errors = {}
    if user_input is not None:
        if self._host_port_alias_already_configured(user_input):
            return self.async_abort(reason="already_configured")
        _, errors = await self._async_validate_or_error(user_input)

        if not errors:
            title = _format_host_port_alias(user_input)
            return self.async_create_entry(title=title, data=user_input)

    return self.async_show_form(
        step_id="user", data_schema=_base_schema({}), errors=errors
    )

The error is raised using async_show_form(), but this is the import step, so how can a form be shown? Is there another way to trigger an error? I cannot find anything in docs.

[DaAwesomeP]

Additionally, how can I stop the integration from appearing in the UI? Currently it is listed and clicking it show a white box that simply says "Aborted."

[MartinHjelmare]

Our config flow should abort on error.

Don't set config flow to true in manifest.json to avoid the integration showing in the integration list in the GUI.

[DaAwesomeP]

Wow the GitHub Actions CI starts up and completes much faster than the Azure Pipelines did. Very smooth! 👏

[DaAwesomeP]

OK, I added two more tests for those two exceptions to maintain coverage. Please let me know if there are any other changes I need to make, and thank you for walking me through this process thus far!

[DaAwesomeP]

OK, let me know if there is anything else that needs to be fixed!

[MartinHjelmare]

Looks good!

[DaAwesomeP]

🎉 🎊 Yay! This was a great learning process for me, thank you! Can't believe it has been so long since I started #24014. 😄 🏠