Merge lp:~gnuoy/charms/trusty/openstack-dashboard/stable-charmhelper-sync into lp:~openstack-charmers-archive/charms/trusty/openstack-dashboard/trunk

[Liam Young]

[Chris Glass (tribaal)]

+1

review: Approve

=== modified file 'hooks/charmhelpers/contrib/openstack/utils.py'
--- hooks/charmhelpers/contrib/openstack/utils.py	2014-05-19 11:42:57 +0000
+++ hooks/charmhelpers/contrib/openstack/utils.py	2014-08-27 07:23:31 +0000
@@ -24,7 +24,7 @@
 )
 
 from charmhelpers.core.host import lsb_release, mounts, umount
-from charmhelpers.fetch import apt_install
+from charmhelpers.fetch import apt_install, apt_cache
 from charmhelpers.contrib.storage.linux.utils import is_block_device, zap_disk
 from charmhelpers.contrib.storage.linux.loopback import ensure_loopback_device
 
@@ -130,13 +130,8 @@
 
 def get_os_codename_package(package, fatal=True):
     '''Derive OpenStack release codename from an installed package.'''
-    apt.init()
-
-    # Tell apt to build an in-memory cache to prevent race conditions (if
-    # another process is already building the cache).
-    apt.config.set("Dir::Cache::pkgcache", "")
-
-    cache = apt.Cache()
+
+    cache = apt_cache()
 
     try:
         pkg = cache[package]

=== modified file 'hooks/charmhelpers/core/host.py'
--- hooks/charmhelpers/core/host.py	2014-08-13 15:55:59 +0000
+++ hooks/charmhelpers/core/host.py	2014-08-27 07:23:31 +0000
@@ -318,12 +318,8 @@
        0 => Installed revno is the same as supplied arg
       -1 => Installed revno is less than supplied arg
     '''
+    from charmhelpers.fetch import apt_cache
     if not pkgcache:
-        apt_pkg.init()
-        # Force Apt to build its cache in memory. That way we avoid race
-        # conditions with other applications building the cache in the same
-        # place.
-        apt_pkg.config.set("Dir::Cache::pkgcache", "")
-        pkgcache = apt_pkg.Cache()
+        pkgcache = apt_cache()
     pkg = pkgcache[package]
     return apt_pkg.version_compare(pkg.current_ver.ver_str, revno)

=== modified file 'hooks/charmhelpers/fetch/__init__.py'
--- hooks/charmhelpers/fetch/__init__.py	2014-08-13 15:55:59 +0000
+++ hooks/charmhelpers/fetch/__init__.py	2014-08-27 07:23:31 +0000
@@ -108,14 +108,8 @@
 
 def filter_installed_packages(packages):
     """Returns a list of packages that require installation"""
-    apt_pkg.init()
-
-    # Tell apt to build an in-memory cache to prevent race conditions (if
-    # another process is already building the cache).
-    apt_pkg.config.set("Dir::Cache::pkgcache", "")
-    apt_pkg.config.set("Dir::Cache::srcpkgcache", "")
-
-    cache = apt_pkg.Cache()
+
+    cache = apt_cache()
     _pkgs = []
     for package in packages:
         try:
@@ -128,6 +122,15 @@
     return _pkgs
 
 
+def apt_cache(in_memory=True):
+    """Build and return an apt cache"""
+    apt_pkg.init()
+    if in_memory:
+        apt_pkg.config.set("Dir::Cache::pkgcache", "")
+        apt_pkg.config.set("Dir::Cache::srcpkgcache", "")
+    return apt_pkg.Cache()
+
+
 def apt_install(packages, options=None, fatal=False):
     """Install one or more packages"""
     if options is None: