Source code for libcloud.common.providers

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Common methods for obtaining a reference to the provider driver class.

__all__ = ["get_driver", "set_driver"]

[docs]def get_driver(drivers, provider, deprecated_providers=None, deprecated_constants=None): """ Get a driver. :param drivers: Dictionary containing valid providers. :type drivers: ``dict`` :param provider: Id (constant) of provider to get the driver for. :type provider: :class:`libcloud.types.Provider` :param: deprecated_providers: Dictionary with information about the deprecated drivers. :type deprecated_providers: ``dict`` :param: deprecated_constants: Dictionary with information about the deprecated provider constants. :type deprecated_constants: ``dict`` """ # Those providers have been shut down or similar. deprecated_providers = deprecated_providers or {} if provider in deprecated_providers: url = deprecated_providers[provider]["url"] reason = deprecated_providers[provider]["reason"] msg = "Provider no longer supported: {}, please visit: {}".format(url, reason) raise Exception(msg) # Those drivers have moved to "region" constructor argument model deprecated_constants = deprecated_constants or {} if provider in deprecated_constants: old_name = provider.upper() new_name = deprecated_constants[provider].upper() url = "" msg = ( 'Provider constant "%s" has been removed. New constant ' 'is now called "%s".\n' "For more information on this change and how to modify your " "code to work with it, please visit: %s" % (old_name, new_name, url) ) raise Exception(msg) if provider in drivers: mod_name, driver_name = drivers[provider] _mod = __import__(mod_name, globals(), locals(), [driver_name]) return getattr(_mod, driver_name) # NOTE: This is for backward compatibility reasons where user could use # a string value instead of a Provider.FOO enum constant and this function # would still work for provider_name, (mod_name, driver_name) in drivers.items(): # NOTE: This works because Provider enum class overloads __eq__ if provider.lower() == provider_name.lower(): _mod = __import__(mod_name, globals(), locals(), [driver_name]) return getattr(_mod, driver_name) raise AttributeError("Provider %s does not exist" % (provider))
[docs]def set_driver(drivers, provider, module, klass): """ Sets a driver. :param drivers: Dictionary to store providers. :param provider: Id of provider to set driver for :type provider: :class:`libcloud.types.Provider` :param module: The module which contains the driver :type module: L :param klass: The driver class name :type klass: """ if provider in drivers: raise AttributeError("Provider %s already registered" % (provider)) drivers[provider] = (module, klass) # Check if this driver is valid try: driver = get_driver(drivers, provider) except (ImportError, AttributeError) as exp: drivers.pop(provider) raise exp return driver