Have requests use Windows certs for TLS/SSL validation

client.py

"""
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"""
import requests


class NoCertsInSystemStore(Exception):
    """
    Raised on Windows when there are no certs in the system store
    """


class MyRequestsBasedAPIClient:
    def __enter__(self):
        self.session = requests.Session()
        # On Windows we need to tell requests not to use it's builtin ca store
        if os.name == "nt":
            ssl_context = ssl.create_default_context()
            self.windows_ca_file = pathlib.Path(
                tempfile.NamedTemporaryFile(suffix=".pem").name
            )
            ca_certs = ssl_context.get_ca_certs(binary_form=True)
            if not ca_certs:
                raise NoCertsInSystemStore()
            self.windows_ca_file.write_text(
                "\n".join(
                    map(
                        ssl.DER_cert_to_PEM_cert,
                        ssl_context.get_ca_certs(binary_form=True),
                    )
                )
            )
            self.session.verify = self.windows_ca_file
        return self

    def __exit__(self, exc_type, exc_value, traceback):
        if os.name == "nt":
            os.unlink(self.windows_ca_file)
            self.windows_ca_file = None
        self.session = None