Function bootstrap_pex

pex/pex_bootstrapper.py:651–705

(
    entry_point,  # type: str
    execute=True,  # type: bool
    venv_dir=None,  # type: Optional[str]
    python_args=(),  # type: Sequence[str]
)

# NB: This helper is used by the PEX bootstrap __main__.py as well as the __pex__/__init__.py
# import hook code.
def bootstrap_pex(
    entry_point,  # type: str
    execute=True,  # type: bool
    venv_dir=None,  # type: Optional[str]
    python_args=(),  # type: Sequence[str]
):
    # type: (...) -> Any

    pex_info = _bootstrap(entry_point)

    # ENV.PEX_ROOT is consulted by PythonInterpreter and Platform so set that up as early as
    # possible in the run.
    with ENV.patch(PEX_ROOT=pex_info.pex_root):
        cache_access.read_write()
        if not execute:
            for location in _activate_pex(entry_point, pex_info, venv_dir=venv_dir):
                from pex.third_party import VendorImporter

                VendorImporter.install(
                    uninstallable=False, prefix="__pex__", path_items=["."], root=location
                )

            from pex import bootstrap

            # For inscrutable reasons, CPython 2.7 (not PyPy 2.7 and not any other CPython or PyPy
            # version supported by Pex) cannot handle pex.third_party being un-imported at this
            # stage; so we just skip that cleanup step for every interpreter to keep things simple.
            # The main point here is that we've un-imported all "exposed" Pex vendored code, notably
            # `attrs`.
            bootstrap.demote(disable_vendor_importer=False)
            return

        interpreter_test = InterpreterTest(entry_point=entry_point, pex_info=pex_info)
        if not (ENV.PEX_UNZIP or ENV.PEX_TOOLS) and pex_info.venv:
            try:
                target = find_compatible_interpreter(
                    interpreter_test=interpreter_test,
                    interpreter_selection_strategy=pex_info.interpreter_selection_strategy,
                )
            except UnsatisfiableInterpreterConstraintsError as e:
                die(str(e))
            venv_pex = _bootstrap_venv(entry_point, interpreter=target)
            venv_pex.execv(python_args=python_args, additional_args=sys.argv[1:])
        else:
            maybe_reexec_pex(
                interpreter_test=interpreter_test,
                interpreter_selection_strategy=pex_info.interpreter_selection_strategy,
                python_args=python_args,
            )
            from . import pex

            try:
                return pex.PEX(entry_point).execute(python_args=python_args)
            except pex.PEX.Error as e:
                return e


def _activate_pex(