Generate requirements.txt and requirements-dev.txt from pyproject.toml

generate_requirements.py

import tomlkit


def format_version_constraint(constraint):
    if constraint.startswith("^"):
        constraint = (
            ">="
            + constraint[1:]
            + ",<"
            + ".".join(
                str(int(part) + 1) if i == 0 else part
                for i, part in enumerate(constraint[1:].split("."))
            )
        )
    else:
        constraint = "==" + constraint
    return constraint


def write_requirements(dependencies, filename):
    with open(filename, "w") as f:
        for package, version in dependencies.items():
            if package.lower() == "python":
                continue

            if isinstance(version, tomlkit.items.InlineTable):
                constraint = format_version_constraint(
                    version.get("version", "*")
                )
                extras = version.get("extras", [])
                if extras:
                    f.write(f"{package}[{','.join(extras)}]{constraint}\n")
                else:
                    f.write(f"{package}{constraint}\n")
            else:
                constraint = format_version_constraint(str(version))
                f.write(f"{package}{constraint}\n")


def main():
    with open("pyproject.toml", "r") as f:
        content = tomlkit.parse(f.read())

    main_dependencies = content["tool"]["poetry"]["dependencies"]
    dev_dependencies = content["tool"]["poetry"]["group"]["dev"][
        "dependencies"
    ]

    write_requirements(main_dependencies, "requirements.txt")
    write_requirements(dev_dependencies, "requirements-dev.txt")


if __name__ == "__main__":
    main()