# Copyright 2018 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

from autotest_lib.client.common_lib import autotemp
from autotest_lib.client.cros.update_engine import nebraska_wrapper
from autotest_lib.client.cros.update_engine import update_engine_test

class autoupdate_UrlSwitch(update_engine_test.UpdateEngineTest):
    """Tests that we can continue with the second url when the first fails."""
    version = 1

    def run_once(self, image_url):
        """
        Runs the URL switch test.

        Test to see whether the update_engine can successfully switch to a
        different URL if one fails.

        @param image_url: The URL of the update payload.
        """

        # Get payload properties file so we can run Nebraska with it.
        metadata_dir = autotemp.tempdir()
        self._get_payload_properties_file(image_url, metadata_dir.name)
        base_url = ''.join(image_url.rpartition('/')[0:2])
        with nebraska_wrapper.NebraskaWrapper(
                log_dir=self.resultsdir,
                update_metadata_dir=metadata_dir.name,
                update_payloads_address=base_url) as nebraska:

            # Start the update that will return two Urls. This matches what test
            # and production omaha does today.
            self._check_for_update(port=nebraska.get_port(), num_urls=2,
                                   critical_update=True)
            self._wait_for_progress(0.2)

            # Pull the network cable so the update fails.
            self._disable_internet()

            # It will retry 21 times before giving up.
            self._wait_for_update_to_fail()

            # Check that we are moving to the next Url.
            self._enable_internet()
            self._check_update_engine_log_for_entry(
                'Reached max number of failures for Url')

            # The next update attempt should resume and finish successfully.
            self._check_for_update(port=nebraska.get_port(),
                                   critical_update=True)
            self._wait_for_update_to_complete()
            self._check_update_engine_log_for_entry(
                'Resuming an update that was previously started.')