Continuously export Memfault chunks from serial port

exporter.py

import pathlib
import subprocess

import click
import serial


def run_cli_post_chunks(output, project_key, device_serial):
    args = [
        "memfault",
        "--project-key",
        project_key,
        "post-chunk",
        "--device-serial",
        device_serial,
        "--encoding",
        "sdk_data_export",
        str(output),
    ]
    subprocess.run(args=args)


@click.command()
@click.argument("device")
@click.argument("output", type=click.Path(exists=False, path_type=pathlib.Path))
@click.option("--project-key", help="Project key to export data to")
@click.option("--device-serial", help="Device serial")
@click.option("--baudrate", default=115200, help="Baudrate of serial port")
@click.option("--timeout", default=60, help="Read timeout before sending batch of chunks")
def read_chunks(device, output, project_key, device_serial, baudrate, timeout):
    if output.exists():
        click.echo(f"Overwriting file {output}")

    port = serial.Serial(device, baudrate=baudrate, timeout=timeout)
    while True:
        with open(output, "wb") as output_file:
            lines = port.readlines()
            output_file.writelines([line + b"\n" for line in lines])
            output_file.flush()
        run_cli_post_chunks(output, project_key, device_serial)


if __name__ == "__main__":
    read_chunks(auto_envvar_prefix="MEMFAULT")