From 1814da42b0759b1d7af89f804499fb63d283152e Mon Sep 17 00:00:00 2001
From: Thomas Leonard <talex5@gmail.com>
Date: Sun, 20 Jun 2010 16:36:27 +0100
Subject: [PATCH] Removed the on-disk apt-cache cache

apt-cache queries no only happen when selection fails, so they're
no longer speed critical.
---
 zeroinstall/injector/distro.py | 66 ++++++++++++++++++++----------------------
 zeroinstall/injector/fetch.py  |  3 +-
 zeroinstall/injector/policy.py |  8 +++++
 3 files changed, 41 insertions(+), 36 deletions(-)

diff --git a/zeroinstall/injector/distro.py b/zeroinstall/injector/distro.py
index 4578ada..6039a01 100644
--- a/zeroinstall/injector/distro.py
+++ b/zeroinstall/injector/distro.py
@@ -320,7 +320,7 @@ class DebianDistribution(Distribution):
 
 	def __init__(self, dpkg_status, pkgcache):
 		self.dpkg_cache = Cache('dpkg-status.cache', dpkg_status, 2)
-		self.apt_cache = Cache('apt-cache-cache', pkgcache, 3)
+		self.apt_cache = {}
 
 	def _query_installed_package(self, package):
 		null = os.open('/dev/null', os.O_WRONLY)
@@ -356,9 +356,9 @@ class DebianDistribution(Distribution):
 		else:
 			installed_version = None
 
-		cached = self.apt_cache.get(package)
-		if cached not in (None, '-'):
-			candidate_version, candidate_arch, candidate_size = cached.split('\t')
+		cached = self.apt_cache.get(package, None)
+		if cached:
+			candidate_version, candidate_arch, candidate_size = cached
 			if candidate_version and candidate_version != installed_version:
 				impl = factory('package:deb:%s:%s' % (package, candidate_version))
 				impl.version = model.parse_version(candidate_version)
@@ -394,36 +394,34 @@ class DebianDistribution(Distribution):
 
 		for package in package_names:
 			# Check to see whether we could get a newer version using apt-get
-			cached = self.apt_cache.get(package)
-			if cached is None:
-				try:
-					null = os.open('/dev/null', os.O_WRONLY)
-					child = subprocess.Popen(['apt-cache', 'show', '--no-all-versions', '--', package], stdout = subprocess.PIPE, stderr = null)
-					os.close(null)
-
-					arch = version = size = None
-					for line in child.stdout:
-						line = line.strip()
-						if line.startswith('Version: '):
-							version = line[9:]
-							if ':' in version:
-								# Debian's 'epoch' system
-								version = version.split(':', 1)[1]
-							version = try_cleanup_distro_version(version)
-						elif line.startswith('Architecture: '):
-							arch = canonical_machine(line[14:].strip())
-						elif line.startswith('Size: '):
-							size = int(line[6:].strip())
-					if version and arch:
-						cached = '%s\t%s\t%d' % (version, arch, size)
-					else:
-						cached = '-'
-					child.wait()
-				except Exception, ex:
-					warn("'apt-cache show %s' failed: %s", package, ex)
-					cached = '-'
-				# (multi-arch support? can there be multiple candidates?)
-				self.apt_cache.put(package, cached)
+			try:
+				null = os.open('/dev/null', os.O_WRONLY)
+				child = subprocess.Popen(['apt-cache', 'show', '--no-all-versions', '--', package], stdout = subprocess.PIPE, stderr = null)
+				os.close(null)
+
+				arch = version = size = None
+				for line in child.stdout:
+					line = line.strip()
+					if line.startswith('Version: '):
+						version = line[9:]
+						if ':' in version:
+							# Debian's 'epoch' system
+							version = version.split(':', 1)[1]
+						version = try_cleanup_distro_version(version)
+					elif line.startswith('Architecture: '):
+						arch = canonical_machine(line[14:].strip())
+					elif line.startswith('Size: '):
+						size = int(line[6:].strip())
+				if version and arch:
+					cached = (version, arch, size)
+				else:
+					cached = None
+				child.wait()
+			except Exception, ex:
+				warn("'apt-cache show %s' failed: %s", package, ex)
+				cached = None
+			# (multi-arch support? can there be multiple candidates?)
+			self.apt_cache[package] = cached
 
 class RPMDistribution(CachedDistribution):
 	"""An RPM-based distribution."""
diff --git a/zeroinstall/injector/fetch.py b/zeroinstall/injector/fetch.py
index d7f33f6..e651296 100644
--- a/zeroinstall/injector/fetch.py
+++ b/zeroinstall/injector/fetch.py
@@ -167,8 +167,7 @@ class Fetcher(object):
 			tasks.check(fetch)
 
 			# Force feed to be regenerated with the new information
-			if feed_url in iface_cache._feeds:
-				del iface_cache._feeds[feed_url]
+			iface_cache.get_feed(feed_url, force = True)
 
 	def download_and_import_feed(self, feed_url, iface_cache, force = False):
 		"""Download the feed, download any required keys, confirm trust if needed and import.
diff --git a/zeroinstall/injector/policy.py b/zeroinstall/injector/policy.py
index cbd3b4b..3f0c0a6 100644
--- a/zeroinstall/injector/policy.py
+++ b/zeroinstall/injector/policy.py
@@ -362,6 +362,14 @@ class Policy(object):
 					del downloads_in_progress[f]
 					downloads_finished.add(f)
 
+					# Need to refetch any "distribution" feed that
+					# depends on this one
+					distro_feed_url = 'distribution:' + f
+					if distro_feed_url in downloads_finished:
+						downloads_finished.remove(distro_feed_url)
+					if distro_feed_url in downloads_in_progress:
+						del downloads_in_progress[distro_feed_url]
+
 	@tasks.async
 	def solve_and_download_impls(self, refresh = False, select_only = False):
 		"""Run L{solve_with_downloads} and then get the selected implementations too.
-- 
2.11.4.GIT