package_manager: Share more common DEB / IPK code

Avoid code duplication by making `extract` a shared method (and
retrieving the package manager specific input via an abstract method).
Additionally, follow Python conventions and prefix class internal
methods with "_" to indicate that they shouldn't be called externally.

(From OE-Core rev: c4b126e216dfe8251ec55074be78188fcc3fcea8)

Signed-off-by: Philip Lorenz <philip.lorenz@bmw.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oe/package_manager/common_deb_ipk.py

@@ -20,9 +20,15 @@ class OpkgDpkgPM(PackageManager):
         """
         super(OpkgDpkgPM, self).__init__(d, target_rootfs)
 
-    def package_info(self, pkg, cmd):
+    def package_info(self, pkg):
         """
         Returns a dictionary with the package info.
+        """
+        raise NotImplementedError
+
+    def _common_package_info(self, cmd):
+        """
+       "Returns a dictionary with the package info.
 
         This method extracts the common parts for Opkg and Dpkg
         """
@@ -36,14 +42,16 @@ class OpkgDpkgPM(PackageManager):
 
         return opkg_query(proc.stdout)
 
-    def extract(self, pkg, pkg_info):
+    def extract(self, pkg):
         """
         Returns the path to a tmpdir where resides the contents of a package.
 
         Deleting the tmpdir is responsability of the caller.
-
-        This method extracts the common parts for Opkg and Dpkg
         """
+        pkg_info = self.package_info(pkg)
+        if not pkg_info:
+            bb.fatal("Unable to get information for package '%s' while "
+                     "trying to extract the package."  % pkg)
 
         ar_cmd = bb.utils.which(os.getenv("PATH"), "ar")
         tar_cmd = bb.utils.which(os.getenv("PATH"), "tar")

meta/lib/oe/package_manager/deb/__init__.py

@@ -7,7 +7,7 @@
 import re
 import subprocess
 from oe.package_manager import *
-from oe.package_manager import OpkgDpkgPM
+from oe.package_manager.common_deb_ipk import OpkgDpkgPM
 
 class DpkgIndexer(Indexer):
     def _create_configs(self):
@@ -431,7 +431,7 @@ class DpkgPM(OpkgDpkgPM):
         Returns a dictionary with the package info.
         """
         cmd = "%s show %s" % (self.apt_cache_cmd, pkg)
-        pkg_info = super(DpkgPM, self).package_info(pkg, cmd)
+        pkg_info = self._common_package_info(cmd)
 
         pkg_arch = pkg_info[pkg]["pkgarch"]
         pkg_filename = pkg_info[pkg]["filename"]
@@ -439,18 +439,3 @@ class DpkgPM(OpkgDpkgPM):
                 os.path.join(self.deploy_dir, pkg_arch, pkg_filename)
 
         return pkg_info
-
-    def extract(self, pkg):
-        """
-        Returns the path to a tmpdir where resides the contents of a package.
-
-        Deleting the tmpdir is responsability of the caller.
-        """
-        pkg_info = self.package_info(pkg)
-        if not pkg_info:
-            bb.fatal("Unable to get information for package '%s' while "
-                     "trying to extract the package."  % pkg)
-
-        tmp_dir = super(DpkgPM, self).extract(pkg, pkg_info)
-
-        return tmp_dir

meta/lib/oe/package_manager/ipk/__init__.py

@@ -416,7 +416,7 @@ class OpkgPM(OpkgDpkgPM):
         Returns a dictionary with the package info.
         """
         cmd = "%s %s info %s" % (self.opkg_cmd, self.opkg_args, pkg)
-        pkg_info = super(OpkgPM, self).package_info(pkg, cmd)
+        pkg_info = self._common_package_info(cmd)
 
         pkg_arch = pkg_info[pkg]["arch"]
         pkg_filename = pkg_info[pkg]["filename"]
@@ -424,16 +424,3 @@ class OpkgPM(OpkgDpkgPM):
                 os.path.join(self.deploy_dir, pkg_arch, pkg_filename)
 
         return pkg_info
-
-    def extract(self, pkg):
-        """
-        Returns the path to a tmpdir where resides the contents of a package.
-
-        Deleting the tmpdir is responsability of the caller.
-        """
-        pkg_info = self.package_info(pkg)
-        if not pkg_info:
-            bb.fatal("Unable to get information for package '%s' while "
-                     "trying to extract the package."  % pkg)
-
-        return super(OpkgPM, self).extract(pkg, pkg_info)