Commit cea54423 authored by Mitchell Hentges's avatar Mitchell Hentges
Browse files

Bug 1738848: Handle virtualenv case where metadata file is missing r=ahal 

At Mach initialization time, it needs to know if it's not running from
the Mach virtualenv so it can decide to insulate itself from the
external sys.path.

However, the current mechanism of detecting the Mach virtualenv
struggles if the venv is old, and therefore missing its metadata file.
In such a case, it's recognized as "not the Mach venv" rather than "an
out-of-date Mach venv".

As part of this, I'm realizing that simply using the metadata file as a
"virtualenv has finished building" marker is insufficient, because it
will cause similar confusion here. This is solved with a "finalization"
key in in the metadata.

Differential Revision: https://phabricator.services.mozilla.com/D130794
parent 370a3a7e

build/mach_initialize.py

+13 −0
Original line number Diff line number Diff line
@@ -182,10 +182,23 @@ def _activate_python_environment(topsrcdir, state_dir): 
    from mach.site import (

        MachSiteManager,

        VirtualenvOutOfDateException,

        MozSiteMetadata,

        MozSiteMetadataOutOfDateError,

    )



    try:

        active_metadata = MozSiteMetadata.from_runtime()

        if not active_metadata and os.path.basename(sys.prefix) == "mach":

            # Until the new "MozVirtualenvMetadata" code has been live for long enough,

            # there will be Mach virtualenvs without associated "metadata" files.

            # Since "active_metadata" will be "None" in these cases, let's try

            # to identify them with a dumb, but mostly correct, "parent directory name"

            # check.

            # If the check matches, then the virtualenv should be re-generated so it

            # gets its metadata file.

            raise MozSiteMetadataOutOfDateError(

                "Mach virtualenv is missing metadata file."

            )

        mach_environment = MachSiteManager.from_environment(

            topsrcdir,

            # normpath state_dir to normalize msys-style slashes.

python/mach/mach/site.py

+18 −6
Original line number Diff line number Diff line
@@ -41,8 +41,12 @@ class MozSiteMetadata: 
        self.site_name = site_name

        self.prefix = prefix



    def write(self):

        raw = {"hex_version": self.hex_version, "virtualenv_name": self.site_name}

    def write(self, is_finalized):

        raw = {

            "hex_version": self.hex_version,

            "virtualenv_name": self.site_name,

            "is_finalized": is_finalized,

        }

        with open(os.path.join(self.prefix, METADATA_FILENAME), "w") as file:

            json.dump(raw, file)
@@ -60,9 +64,16 @@ class MozSiteMetadata: 
    @classmethod

    def from_path(cls, prefix):

        metadata_path = os.path.join(prefix, METADATA_FILENAME)

        out_of_date_exception = MozSiteMetadataOutOfDateError(

            f'The virtualenv at "{prefix}" is out-of-date.'

        )

        try:

            with open(metadata_path, "r") as file:

                raw = json.load(file)



            if not raw.get("is_finalized", False):

                raise out_of_date_exception



            return cls(

                raw["hex_version"],

                raw["virtualenv_name"],
@@ -71,9 +82,7 @@ class MozSiteMetadata: 
        except FileNotFoundError:

            return None

        except KeyError:

            raise MozSiteMetadataOutOfDateError(

                f'The moz site metadata at "{metadata_path}" is out-of-date.'

            )

            raise out_of_date_exception





class SitePackagesSource(enum.Enum):
@@ -557,6 +566,9 @@ def _create_venv_with_pthfile( 
    if os.path.exists(virtualenv_root):

        shutil.rmtree(virtualenv_root)



    os.makedirs(virtualenv_root)

    metadata.write(is_finalized=False)



    subprocess.check_call(

        [

            sys.executable,
@@ -595,7 +607,7 @@ def _create_venv_with_pthfile( 
                )



    os.utime(target_venv.activate_path, None)

    metadata.write()

    metadata.write(is_finalized=True)





def _is_venv_up_to_date(