Class Variables

pex/variables.py:177–786

Environment variables supported by the PEX runtime.

class Variables(object):
    """Environment variables supported by the PEX runtime."""

    @classmethod
    def process_pydoc(cls, pydoc):
        # type: (Optional[str]) -> Tuple[str, str]
        if pydoc is None:
            return "Unknown", "Unknown"
        pydoc_lines = pydoc.splitlines()
        variable_type = pydoc_lines[0]
        variable_text = " ".join(filter(None, (line.strip() for line in pydoc_lines[2:])))
        return variable_type, variable_text

    @classmethod
    def iter_help(cls):
        # type: () -> Iterator[Tuple[str, str, str]]
        for variable_name, value in sorted(cls.__dict__.items()):
            if not variable_name.startswith("PEX_"):
                continue
            value = value._func if isinstance(value, DefaultedProperty) else value
            variable_type, variable_text = cls.process_pydoc(getattr(value, "__doc__"))
            yield variable_name, variable_type, variable_text

    @classmethod
    def from_rc(cls, rc=None):
        # type: (Optional[str]) -> Dict[str, str]
        """Read pex runtime configuration variables from a pexrc file.

        :param rc: an absolute path to a pexrc file.
        :return: A dict of key value pairs found in processed pexrc files.
        """
        ret_vars = {}  # type: Dict[str, str]
        rc_locations = [
            os.path.join(os.sep, "etc", "pexrc"),
            os.path.join("~", ".pexrc"),
            os.path.join(os.path.dirname(sys.argv[0]), ".pexrc"),
        ]
        if rc:
            rc_locations.append(rc)
        for filename in rc_locations:
            try:
                with open(os.path.expanduser(filename)) as fh:
                    rc_items = map(cls._get_kv, fh)
                    ret_vars.update(dict(filter(None, rc_items)))
            except IOError:
                continue
        return ret_vars

    @classmethod
    def _get_kv(cls, variable):
        kv = variable.strip().split("=")
        if len(list(filter(None, kv))) == 2:
            return kv

    @staticmethod
    def _maybe_get_bool_var(
        name,  # type: str
        env,  # type: Mapping[str, Optional[str]]