oslo.upgradecheck/doc/source/usage.rst

Usage

See the module oslo_upgradecheck.__main__ for an example of how to use this project.

Each consuming project should create a class that inherits from oslo_upgradecheck.upgradecheck.UpgradeCommands and implement check methods on it. Those check methods should then be added to the _upgrade_checks tuple so they will be run when the oslo_upgradecheck.upgradecheck.UpgradeCommands.check method is called. For example:

from oslo_upgradecheck import upgradecheck

class ProjectSpecificUpgradeCommands(upgradecheck.UpgradeCommands):
    def an_upgrade_check(self):
        if everything_is_awesome():
            return upgradecheck.UpgradeCheckResult(
                upgradecheck.UpgradeCheckCode.SUCCESS, 'Success details')
        else:
            return upgradecheck.UpgradeCheckResult(
                upgradecheck.UpgradeCheckCode.FAILURE, 'Failure details')

    _upgrade_checks = (('Awesome upgrade check', an_upgrade_check))

oslo.upgradecheck also includes a basic implementation of command line argument handling that can be used to provide the minimum processing needed to implement a $SERVICE-status upgrade check command. To make use of it, write a method that creates an instance of the class created above, then pass that class's check method into oslo_upgradecheck.upgradecheck.main. For example:

def main():
    inst = ProjectSpecificUpgradeCommands()
    return upgradecheck.main(inst.check)

The entry point for the $SERVICE-status command should then point at this method.

Alternatively, if a project has its own CLI code that it would prefer to reuse, it simply needs to ensure that the inst.check method is called when the upgrade check parameters are passed to the $SERVICE-status command.