Export the packages anvil requires.

Export and ensure that we don't remove the
dependencies that anvil and openstack source
directories requires to operate.

- d2to1 is required to even run setup.py
- setuptools-git (the same)
- pbr (the same)

Fixes bug: #1189707

Change-Id: I099856eba07784afa2b65c3e4ebf6c0abcaab4bd

anvil/packaging/base.py

@@ -77,7 +77,6 @@ class DependencyHandler(object):
         self.distro = distro
         self.root_dir = root_dir
         self.instances = instances
-
         self.deps_dir = sh.joinpths(self.root_dir, "deps")
         self.download_dir = sh.joinpths(self.deps_dir, "download")
         self.log_dir = sh.joinpths(self.deps_dir, "output")
@@ -88,10 +87,17 @@ class DependencyHandler(object):
         self.pip_executable = str(self.distro.get_command_config('pip'))
         self.pips_to_install = []
         self.forced_packages = []
-        # these packages conflict with our deps and must be removed
+        # These packages conflict with our deps and must be removed
         self.nopackages = []
         self.package_dirs = self._get_package_dirs(instances)
-        self.python_names = self._get_python_names(self.package_dirs)
+        # Instantiate this as late as we can.
+        self._python_names = None
+
+    @property
+    def python_names(self):
+        if self._python_names is None:
+            self._python_names  = self._get_python_names(self.package_dirs)
+        return self._python_names
 
     @staticmethod
     def _get_package_dirs(instances):

anvil/packaging/yum.py

@@ -21,6 +21,7 @@ import sys
 from datetime import datetime
 
 from anvil import colorizer
+from anvil import env
 from anvil import log as logging
 from anvil.packaging import base
 from anvil.packaging.helpers import pip_helper
@@ -412,11 +413,17 @@ BuildArch: noarch
             sh.unlink(self.tracereader.filename())
             self.tracereader = None
 
+        # Don't take out packages that anvil requires to run...
+        no_remove = os.env.get_key('REQUIRED_PACKAGES', '').split()
+        no_remove = sorted(set(no_remove))
         rpm_names = []
         for name in self._convert_names_python2rpm(self.python_names):
-            if self.helper.is_installed(name):
+            if self.helper.is_installed(name) and name not in no_remove:
                 rpm_names.append(name)
 
         if rpm_names:
-            cmdline = ["yum", "remove", "--remove-leaves", "-y"] + rpm_names
+            cmdline = ["yum", "remove", "--remove-leaves", "-y"]
+            for p in no_remove:
+                cmdline.append("--exclude=%s" % (p))
+            cmdline.extend(rpm_names)
             sh.execute(cmdline, stdout_fh=sys.stdout, stderr_fh=sys.stderr)