def providers_for(self, vpkg_spec):
if self.provider_index is None:
self.provider_index = ProviderIndex(self.all_package_names())
providers = self.provider_index.providers_for(vpkg_spec)
if not providers:
raise UnknownPackageError("No such virtual package: %s" % vpkg_spec)
return providers
class PackageDB(object):
def __init__(self, root):
"""Construct a new package database from a root directory."""
self.root = root
self.instances = {}
self.provider_index = None
@_autospec
def get(self, spec):
if spec.virtual:
raise UnknownPackageError(spec.name)
if not spec in self.instances:
package_class = self.get_class_for_package_name(spec.name)
self.instances[spec.name] = package_class(spec)
return self.instances[spec.name]
@_autospec
def get_installed(self, spec):
"""Get all the installed specs that satisfy the provided spec constraint."""
return [s for s in self.installed_package_specs() if s.satisfies(spec)]
@_autospec
def providers_for(self, vpkg_spec):
if self.provider_index is None:
self.provider_index = ProviderIndex(self.all_package_names())
providers = self.provider_index.providers_for(vpkg_spec)
if not providers:
raise UnknownPackageError("No such virtual package: %s" % vpkg_spec)
return providers
def dirname_for_package_name(self, pkg_name):
"""Get the directory name for a particular package. This is the
directory that contains its package.py file."""
return join_path(self.root, pkg_name)
def filename_for_package_name(self, pkg_name):
"""Get the filename for the module we should load for a particular
package. Packages for a pacakge DB live in
``$root/<package_name>/package.py``
This will return a proper package.py path even if the
package doesn't exist yet, so callers will need to ensure
the package exists before importing.
"""
validate_module_name(pkg_name)
pkg_dir = self.dirname_for_package_name(pkg_name)
return join_path(pkg_dir, _package_file_name)
def installed_package_specs(self):
"""Read installed package names straight from the install directory
layout.
"""
return spack.install_layout.all_specs()
@memoized
def all_package_names(self):
"""Generator function for all packages. This looks for
``<pkg_name>/package.py`` files within the root direcotry"""
all_package_names = []
for pkg_name in os.listdir(self.root):
pkg_dir = join_path(self.root, pkg_name)
pkg_file = join_path(pkg_dir, _package_file_name)
if os.path.isfile(pkg_file):
all_package_names.append(pkg_name)
all_package_names.sort()
return all_package_names
def all_packages(self):
for name in self.all_package_names():
yield self.get(name)
def exists(self, pkg_name):
"""Whether a package with the supplied name exists ."""
return os.path.exists(self.filename_for_package_name(pkg_name))
@memoized
def get_class_for_package_name(self, pkg_name):
"""Get an instance of the class for a particular package.
This method uses Python's ``imp`` package to load python
source from a Spack package's ``package.py`` file. A
normal python import would only load each package once, but
because we do this dynamically, the method needs to be
memoized to ensure there is only ONE package class
instance, per package, per database.
"""
file_path = self.filename_for_package_name(pkg_name)
if os.path.exists(file_path):
if not os.path.isfile(file_path):
tty.die("Something's wrong. '%s' is not a file!" % file_path)
if not os.access(file_path, os.R_OK):
tty.die("Cannot read '%s'!" % file_path)
else:
raise UnknownPackageError(pkg_name)
class_name = mod_to_class(pkg_name)
try:
module_name = _imported_packages_module + '.' + pkg_name
module = imp.load_source(module_name, file_path)
except ImportError, e:
tty.die("Error while importing %s from %s:\n%s" % (
pkg_name, file_path, e.message))
cls = getattr(module, class_name)
if not inspect.isclass(cls):
tty.die("%s.%s is not a class" % (pkg_name, class_name))
return cls
