Support for Elementary OS (#10)

apt_mirror_updater/__init__.py

@@ -1,7 +1,7 @@
 # Automated, robust apt-get mirror selection for Debian and Ubuntu.
 #
 # Author: Peter Odding <peter@peterodding.com>
-# Last Change: April 17, 2020
+# Last Change: April 18, 2020
 # URL: https://apt-mirror-updater.readthedocs.io
 
 """
@@ -154,8 +154,8 @@ def backend(self):
         :raises: :exc:`~exceptions.EnvironmentError` when no matching backend
                  module is available.
         """
-        logger.debug("Checking whether %s platform is supported ..", self.distributor_id.capitalize())
         module_path = "%s.backends.%s" % (__name__, self.distributor_id)
+        logger.debug("Checking if '%s' module can be imported ..", module_path)
         try:
             __import__(module_path)
         except ImportError:
@@ -522,7 +522,7 @@ def create_chroot(self, directory, arch=None):
             if arch:
                 debootstrap_command.append('--arch=%s' % arch)
             debootstrap_command.append('--keyring=%s' % self.release.keyring_file)
-            debootstrap_command.append(self.distribution_codename)
+            debootstrap_command.append(self.release.upstream_series)
             debootstrap_command.append(directory)
             debootstrap_command.append(self.best_mirror)
             self.context.execute(*debootstrap_command, sudo=True)
@@ -865,9 +865,9 @@ def release_gpg_url(self):
         :attr:`~AptMirrorUpdater.distribution_codename` property of the
         :attr:`updater` object.
         """
-        if self.updater and self.updater.distribution_codename:
+        if self.updater and self.updater.release.upstream_series:
             return '%s/dists/%s/Release.gpg' % (
-                self.mirror_url, self.updater.distribution_codename,
+                self.mirror_url, self.updater.release.upstream_series,
             )
 
     @mutable_property

apt_mirror_updater/backends/elementary.py

@@ -0,0 +1,117 @@
+# Automated, robust apt-get mirror selection for Debian and Ubuntu.
+#
+# Author: Peter Odding <peter@peterodding.com>
+# Last Change: April 16, 2020
+# URL: https://apt-mirror-updater.readthedocs.io
+
+"""
+Support for `Elementary OS`_ package archive mirror selection.
+
+Elementary OS is based on Ubuntu LTS releases and as such this module is a very
+thin wrapper for the :mod:`apt_mirror_updater.backends.ubuntu` module.
+
+.. _Elementary OS: https://en.wikipedia.org/wiki/Elementary_OS
+"""
+
+# Standard library modules.
+import datetime
+import decimal
+
+# Modules included in our package.
+from apt_mirror_updater.backends import ubuntu
+from apt_mirror_updater.releases import Release
+
+# Public identifiers that require documentation.
+__all__ = (
+    'KNOWN_RELEASES',
+    'OLD_RELEASES_URL',
+    'SECURITY_URL',
+    'discover_mirrors',
+    'generate_sources_list',
+)
+
+OLD_RELEASES_URL = ubuntu.OLD_RELEASES_URL
+"""Alias for :attr:`apt_mirror_updater.backends.ubuntu.OLD_RELEASES_URL`."""
+
+SECURITY_URL = ubuntu.SECURITY_URL
+"""Alias for :attr:`apt_mirror_updater.backends.ubuntu.SECURITY_URL`."""
+
+discover_mirrors = ubuntu.discover_mirrors
+"""Alias for :func:`apt_mirror_updater.backends.ubuntu.discover_mirrors`."""
+
+generate_sources_list = ubuntu.generate_sources_list
+"""Alias for :func:`apt_mirror_updater.backends.ubuntu.generate_sources_list`."""
+
+KNOWN_RELEASES = [
+    Release(
+        codename='Jupiter',
+        created_date=datetime.date(2011, 3, 31),
+        distributor_id='elementary',
+        upstream_distributor_id='ubuntu',
+        upstream_series='maverick',
+        upstream_version=decimal.Decimal('10.10'),
+        is_lts=False,
+        series='jupiter',
+        version=decimal.Decimal('0.1'),
+    ),
+    Release(
+        codename='Luna',
+        created_date=datetime.date(2013, 8, 10),
+        distributor_id='elementary',
+        upstream_distributor_id='ubuntu',
+        upstream_series='precise',
+        upstream_version=decimal.Decimal('12.04'),
+        is_lts=False,
+        series='luna',
+        version=decimal.Decimal('0.2'),
+    ),
+    Release(
+        codename='Freya',
+        created_date=datetime.date(2015, 4, 11),
+        distributor_id='elementary',
+        upstream_distributor_id='ubuntu',
+        upstream_series='trusty',
+        upstream_version=decimal.Decimal('14.04'),
+        is_lts=False,
+        series='freya',
+        version=decimal.Decimal('0.3'),
+    ),
+    Release(
+        codename='Loki',
+        created_date=datetime.date(2016, 9, 9),
+        distributor_id='elementary',
+        upstream_distributor_id='ubuntu',
+        upstream_series='xenial',
+        upstream_version=decimal.Decimal('16.04'),
+        is_lts=False,
+        series='loki',
+        version=decimal.Decimal('0.4'),
+    ),
+    Release(
+        codename='Juno',
+        created_date=datetime.date(2018, 10, 16),
+        distributor_id='elementary',
+        upstream_distributor_id='ubuntu',
+        upstream_series='bionic',
+        upstream_version=decimal.Decimal('18.04'),
+        is_lts=False,
+        series='juno',
+        version=decimal.Decimal('5.0'),
+    ),
+    Release(
+        codename='Hera',
+        created_date=datetime.date(2019, 12, 3),
+        distributor_id='elementary',
+        upstream_distributor_id='ubuntu',
+        upstream_series='bionic',
+        upstream_version=decimal.Decimal('18.04'),
+        is_lts=False,
+        series='hera',
+        version=decimal.Decimal('5.1'),
+    ),
+]
+"""
+List of :class:`.Release` objects corresponding to known elementary OS
+releases based on the summary table on the following web page:
+https://en.wikipedia.org/wiki/Elementary_OS#Summary_table
+"""

apt_mirror_updater/releases.py

@@ -1,7 +1,7 @@
 # Easy to use metadata on Debian and Ubuntu releases.
 #
 # Author: Peter Odding <peter@peterodding.com>
-# Last Change: April 16, 2020
+# Last Change: April 18, 2020
 # URL: https://apt-mirror-updater.readthedocs.io
 
 """
@@ -123,18 +123,20 @@ def coerce_release(value):
 @cached
 def discover_releases():
     """
-    Discover known Debian and Ubuntu releases.
+    Discover known Debian, Elementary OS and Ubuntu releases.
 
     :returns: A list of discovered :class:`Release` objects sorted by
              :attr:`~Release.distributor_id` and :attr:`~Release.version`.
 
     The first time this function is called it will try to parse the CSV files
     in ``/usr/share/distro-info`` using :func:`parse_csv_file()` and merge any
     releases it finds with the releases embedded into the source code of this
-    module. The result is cached and returned each time the function is called.
-    It's not a problem if the ``/usr/share/distro-info`` directory doesn't
-    exist or doesn't contain any ``*.csv`` files (it won't cause a warning or
-    error). Of course in this case only the embedded releases will be returned.
+    module and the releases defined by
+    :data:`apt_mirror_updater.backends.elementary.KNOWN_RELEASES`. The result
+    is cached and returned each time the function is called. It's not a problem
+    if the ``/usr/share/distro-info`` directory doesn't exist or doesn't
+    contain any ``*.csv`` files (it won't cause a warning or error). Of course
+    in this case only the embedded releases will be returned.
     """
     # Discover the known releases on the first call to discover_releases().
     # First we check the CSV files on the system where apt-mirror-updater
@@ -144,10 +146,14 @@ def discover_releases():
     for filename in glob.glob(os.path.join(DISTRO_INFO_DIRECTORY, '*.csv')):
         for release in parse_csv_file(filename):
             result.add(release)
-    # Add the releases bundled with apt-mirror-updater to the result
-    # without causing duplicate entries (due to the use of a set and key
+    # Add the Debian and Ubuntu releases bundled with apt-mirror-updater to the
+    # result without causing duplicate entries (due to the use of a set and key
     # properties).
     result.update(BUNDLED_RELEASES)
+    # Add the Elementary OS releases bundled with apt-mirror-updater.
+    # We import the known releases here to avoid circular imports.
+    from apt_mirror_updater.backends import elementary
+    result.update(elementary.KNOWN_RELEASES)
     # Sort the releases by distributor ID and version / series.
     return sorted(result, key=lambda r: (r.distributor_id, r.version or 0, r.series))
 
@@ -240,7 +246,7 @@ def ubuntu_keyring_updated():
 
 class Release(PropertyManager):
 
-    """Data class for metadata on Debian and Ubuntu releases."""
+    """Data class for metadata on Debian, Elementary OS and Ubuntu releases."""
 
     @key_property
     def codename(self):
@@ -252,7 +258,7 @@ def created_date(self):
 
     @key_property
     def distributor_id(self):
-        """The name of the distributor (a string like ``debian`` or ``ubuntu``)."""
+        """The name of the distributor (one of the strings ``debian``, ``elementary`` or ``ubuntu``)."""
 
     @writable_property
     def eol_date(self):
@@ -283,6 +289,21 @@ def release_date(self):
     def series(self):
         """The short version of :attr:`codename` (a string)."""
 
+    @writable_property
+    def upstream_distributor_id(self):
+        """The upstream distributor ID (a string, defaults to :attr:`distributor_id`)."""
+        return self.distributor_id
+
+    @writable_property
+    def upstream_series(self):
+        """The upstream series (a string, defaults to :attr:`series`)."""
+        return self.series
+
+    @writable_property
+    def upstream_version(self):
+        """The upstream version (a string, defaults to :attr:`version`)."""
+        return self.version
+
     @writable_property
     def version(self):
         """
@@ -304,12 +325,12 @@ def keyring_file(self):
         filename = None
         reason = None
         logger.debug("Selecting keyring file for %s ..", self)
-        if self.distributor_id == 'debian':
+        if self.upstream_distributor_id == 'debian':
             filename = DEBIAN_KEYRING_CURRENT
             reason = "only known keyring"
-        elif self.distributor_id == 'ubuntu':
+        elif self.upstream_distributor_id == 'ubuntu':
             if ubuntu_keyring_updated():
-                if self.version > decimal.Decimal('12.04'):
+                if self.upstream_version > decimal.Decimal('12.04'):
                     filename = UBUNTU_KEYRING_CURRENT
                     reason = "new keyring package / new release"
                 else:
@@ -337,6 +358,8 @@ def __str__(self):
         if self.version:
             label.append(str(self.version))
         label.append("(%s)" % self.series)
+        if self.upstream_distributor_id and self.upstream_version:
+            label.extend(("based on", self.upstream_distributor_id.title(), str(self.upstream_version)))
         return " ".join(label)
 
 
@@ -349,9 +372,17 @@ def __str__(self):
 # indent = " " * 4
 # cog.out("\nBUNDLED_RELEASES = [\n")
 # for release in discover_releases():
+#     if release.distributor_id == 'elementary':
+#         # Don't duplicate the Elementary OS releases.
+#         continue
 #     cog.out(indent + "Release(\n")
 #     for name in release.find_properties(cached=False):
 #         value = getattr(release, name)
+#         if ((name == 'upstream_distributor_id' and value == release.distributor_id) or
+#                 (name == 'upstream_series' and value == release.series) or
+#                 (name == 'upstream_version' and value == release.version)):
+#             # Skip redundant values.
+#             continue
 #         if value is not None:
 #             if isinstance(value, decimal.Decimal):
 #                 # It seems weirdly inconsistency to me that this is needed

docs/api.rst

@@ -19,6 +19,12 @@ the `apt-mirror-updater` package. The following modules are available:
 .. automodule:: apt_mirror_updater.backends.debian
    :members:
 
+:mod:`apt_mirror_updater.backends.elementary`
+---------------------------------------------
+
+.. automodule:: apt_mirror_updater.backends.elementary
+   :members:
+
 :mod:`apt_mirror_updater.backends.ubuntu`
 -----------------------------------------