def update()

in build/fbcode_builder/getdeps/fetcher.py [0:0]

• 41 lines of code
• 17 McCabe index (conditional complexity)

    def update(self) -> ChangeStatus:
        try:
            with open(self.hash_file, "r") as f:
                saved_hash = f.read().strip()
                if saved_hash == self.sha256 and os.path.exists(self.src_dir):
                    # Everything is up to date
                    return ChangeStatus()
                print(
                    "saved hash %s doesn't match expected hash %s, re-validating"
                    % (saved_hash, self.sha256)
                )
                os.unlink(self.hash_file)
        except EnvironmentError:
            pass

        # If we got here we know the contents of src_dir are either missing
        # or wrong, so blow away whatever happened to be there first.
        if os.path.exists(self.src_dir):
            shutil.rmtree(self.src_dir)

        # If we already have a file here, make sure it looks legit before
        # proceeding: any errors and we just remove it and re-download
        if os.path.exists(self.file_name):
            try:
                self._verify_hash()
            except Exception:
                if os.path.exists(self.file_name):
                    os.unlink(self.file_name)

        if not os.path.exists(self.file_name):
            self._download()

        if tarfile.is_tarfile(self.file_name):
            opener = tarfile.open
        elif zipfile.is_zipfile(self.file_name):
            opener = zipfile.ZipFile
        else:
            raise Exception("don't know how to extract %s" % self.file_name)
        os.makedirs(self.src_dir)
        print("Extract %s -> %s" % (self.file_name, self.src_dir))
        t = opener(self.file_name)
        if is_windows():
            # Ensure that we don't fall over when dealing with long paths
            # on windows
            src = r"\\?\%s" % os.path.normpath(self.src_dir)
        else:
            src = self.src_dir
        # The `str` here is necessary to ensure that we don't pass a unicode
        # object down to tarfile.extractall on python2.  When extracting
        # the boost tarball it makes some assumptions and tries to convert
        # a non-ascii path to ascii and throws.
        src = str(src)
        t.extractall(src)

        with open(self.hash_file, "w") as f:
            f.write(self.sha256)

        return ChangeStatus(True)