Merge lp:~lool/xdeb/dont-load-apt-cache-on-import into lp:xdeb

[Loïc Minier]

This speeds up importing aptutils.py and xdeb.py by deferring the cache = apt.Cache() in aptutils, which also speeds up running the testsutie; I've also added some progress messages for this step.

It's a bit ugly that xdeb.py functions have to call init_pkg_cache() (NB: the init_cache() name is used in another function in xdeb already), but I couldn't implement __get__()-style hooks here as "aptutils.cache" isn't in a class. We could either move to an aptutils.get_cache() method or move progressively to something like a XdebContext class which would hold things like an apt.Cache() and other globals, and which could use __get__ tricks.

Unmerged revisions

300. By Loïc Minier on 2011-10-19

Add progress message when rebuilding package cache.

299. By Loïc Minier on 2011-10-19

Defer building cache = apt.Cache() in aptutils as this is lengthy; call sites
need to init_pkg_cache() first.

=== modified file 'aptutils.py'
--- aptutils.py	2011-09-26 16:48:55 +0000
+++ aptutils.py	2011-10-19 13:59:23 +0000
@@ -20,7 +20,7 @@
 import utils
 
 
-cache = apt.Cache()
+cache = None
 
 srcrec = None
 pkgsrc = None
@@ -51,12 +51,14 @@
 
 
 def reopen_cache():
+    print "Rebuilding package cache ..."
     cache.open()
 
 
 def update_destdir(options):
     # We can't use this until we've stopped using apt-get to install
     # build-dependencies.
+    #init_pkg_cache()
     #cache.update(sources_list='%s.destdir' % sources_list_path(options))
     command = ['apt-get']
     command.extend(apt_options(options))
@@ -155,6 +157,16 @@
     update_apt_repository(options)
 
 
+def init_pkg_cache():
+    """Build package cache."""
+    global cache
+    if cache is not None:
+        return
+
+    print "Building package cache ..."
+    cache = apt.Cache()
+
+
 def init_src_cache():
     """Build a source package cache."""
     global srcrec, pkgsrc
@@ -224,6 +236,7 @@
 
 def get_real_pkg(pkg):
     """Get the real name of binary package pkg, resolving Provides."""
+    init_pkg_cache()
     if pkg in cache and cache[pkg].versions:
         return pkg
     elif pkg in seen_providers:
@@ -279,6 +292,7 @@
 
 def get_pkg_record(pkg):
     """Return a parsed binary package record for binary package pkg."""
+    init_pkg_cache()
     return deb822.Packages(str(cache[pkg].candidate.record))
 
 
@@ -292,6 +306,7 @@
 
 def get_src_binaries(src):
     """Return all the binaries produced by source package src."""
+    init_pkg_cache()
     record = get_src_record(src)
     if record is not None:
         bins = [b[0]['name'] for b in record.relations['binary']]

=== modified file 'xdeb.py'
--- xdeb.py	2011-10-05 15:19:38 +0000
+++ xdeb.py	2011-10-19 13:59:23 +0000
@@ -418,6 +418,8 @@
 re_deb_filename = re.compile(r"(.+?)_(.+?)_(.+)\.deb$")
 
 def install_build_depends(options, srcs):
+    aptutils.init_pkg_cache()
+
     available_builddeps = set()
     if options.architecture != build_arch:
         if ('binutils-multiarch' in aptutils.cache and
@@ -699,6 +701,8 @@
 
     aptutils.update_apt_repository(options, force_rebuild=previously_built)
 
+    aptutils.init_apt_cache()
+
     if previously_built:
         # We'll need to install all these again.
         command = ['apt-get', '-y']