def check_modules(install=False):
"""
Check for the presence of various required modules.
If the ``install`` parameter is ``True``, an attempt will be made to
install missing modules using :func:`install_package`. Any available
required modules will be loaded into the running process as a side-effect
of running this function.
"""
missing = set()
# Try to load all the modules in our required set. If we fail, add the
# missing modules to the missing set.
for module in _REQUIRE_MODULES:
try:
import_module(module)
except ImportError:
logger.debug("Detected missing required module: {mod}".format(
mod=module))
missing.add(module)
# Have we already got all the modules? Great!
if not missing:
return
# Have we been asked to install the missing ones?
if not install:
raise EnvironmentException(
"Required Python modules are missing: {modules}".format(
modules=", ".join(sorted(missing))))
# Now try to install the missing modules
for module in missing:
logger.info("Installing Python module: {mod}".format(mod=module))
install_package(_REQUIRE_MODULES[module])
# Re-check all the modules
missing.clear()
for module in _REQUIRE_MODULES:
try:
import_module(module)
except ImportError:
logger.debug("Detected missing required module: {mod}".format(
mod=module))
missing.add(module)
if not missing:
return
# We failed to install the modules :-(
raise EnvironmentException(
"Required Python modules could not be installed: {modules}".format(
modules=", ".join(sorted(missing))))
def __locate(cls, module):
try:
return cls.__registered[module]
except KeyError:
pass
try:
import_module(module)
except ImportError:
raise AcquisitionError(
"Cannot import acquirer module {mod}.".format(mod=module))
try:
return cls.__registered[module]
except KeyError:
raise AcquisitionError(
"Could not find any registered acquirer modules in {mod}"
.format(mod=module))
def __locate(cls, module):
try:
return cls.__registered[module]
except KeyError:
pass
try:
import_module(module)
except ImportError:
raise DeploymentError(
"Cannot import deployment handler module {mod}.".format(
mod=module))
try:
return cls.__registered[module]
except KeyError:
raise DeploymentError(
"Could not find any registered deployment modules in {mod}"
.format(mod=module))
