hope to fix sync problems of multiple cache writers

flush, invalidate where needed

pisi/__init__.py

@@ -62,10 +62,6 @@ def _cleanup():
     if filesdb.is_initialized():
         filesdb.close()
 
-    installdb = pisi.db.installdb.InstallDB()
-    if installdb.is_initialized():
-        installdb.close()
-
     if ctx.build_leftover and os.path.exists(ctx.build_leftover):
         os.unlink(ctx.build_leftover)
 

pisi/api.py

@@ -65,8 +65,10 @@ def locked(func):
             raise pisi.errors.AnotherInstanceError(_("Another instance of PiSi is running. Only one instance is allowed."))
 
         try:
+            pisi.db.invalidate_caches()
             return func(*__args,**__kw)
         finally:
+            pisi.db.update_caches()
             lock.close()
     return wrapper
 
@@ -646,6 +648,7 @@ def add_repo(name, indexuri, at = None):
     else:
         repo = pisi.db.repodb.Repo(pisi.uri.URI(indexuri))
         repodb.add_repo(name, repo, at = at)
+        pisi.db.flush_caches()
         ctx.ui.info(_('Repo %s added to system.') % name)
 
 @locked
@@ -653,6 +656,7 @@ def remove_repo(name):
     repodb = pisi.db.repodb.RepoDB()
     if repodb.has_repo(name):
         repodb.remove_repo(name)
+        pisi.db.flush_caches()
         ctx.ui.info(_('Repo %s removed from system.') % name)
     else:
         raise pisi.Error(_('Repository %s does not exist. Cannot remove.')
@@ -663,14 +667,13 @@ def update_repos(repos, force=False):
     pisi.db.historydb.HistoryDB().create_history("repoupdate")
     for repo in repos:
         __update_repo(repo, force)
-    pisi.db.reload()
-
+    pisi.db.flush_caches()
 
 @locked
 def update_repo(repo, force=False):
     pisi.db.historydb.HistoryDB().create_history("repoupdate")
     __update_repo(repo, force)
-    pisi.db.reload()
+    pisi.db.flush_caches()
 
 def __update_repo(repo, force=False):
     ctx.ui.info(_('* Updating repository: %s') % repo)

pisi/db/__init__.py

@@ -10,9 +10,19 @@
 # Please read the COPYING file.
 #
 
-import pisi
+def invalidate_caches():
+    # Invalidates pisi caches in use and forces to re-fill caches from disk when needed
+    for db in [packagedb.PackageDB(), sourcedb.SourceDB(), componentdb.ComponentDB(), installdb.InstallDB()]:
+        db.invalidate()
 
-def reload():
-    pisi.db.packagedb.PackageDB().reload()
-    pisi.db.sourcedb.SourceDB().reload()
-    pisi.db.componentdb.ComponentDB().reload()
+def flush_caches():
+    # Invalidate and flush caches to re-generate them when needed
+    for db in [packagedb.PackageDB(), sourcedb.SourceDB(), componentdb.ComponentDB()]:
+        db.invalidate()
+        db.cache_flush()
+
+def update_caches():
+    # Updates ondisk caches
+    for db in [packagedb.PackageDB(), sourcedb.SourceDB(), componentdb.ComponentDB(), installdb.InstallDB()]:
+        if db.is_initialized():
+            db.cache_save()

pisi/db/lazydb.py

@@ -16,10 +16,17 @@ import time
 import pisi.context as ctx
 
 class Singleton(object):
+    _the_instances = {}
     def __new__(type):
-        if not '_the_instance' in type.__dict__:
-            type._the_instance = object.__new__(type)
-        return type._the_instance
+        if not type.__name__ in Singleton._the_instances:
+            Singleton._the_instances[type.__name__] = object.__new__(type)
+        return Singleton._the_instances[type.__name__]
+
+    def _instance(self):
+        return self._the_instances[type(self).__name__]
+
+    def _delete(self):
+        del self._the_instances[type(self).__name__]
 
 class LazyDB(Singleton):
     def __init__(self, cacheable=False):
@@ -32,12 +39,12 @@ class LazyDB(Singleton):
 
     def cache_save(self):
         if os.access("/var/cache/pisi", os.W_OK) and self.cacheable:
-            cPickle.dump(self.__class__._the_instance.__dict__,
+            cPickle.dump(self._instance().__dict__,
                          file('/var/cache/pisi/%s.cache' % self.__class__.__name__.lower(), 'wb'), 1)
 
     def cache_load(self):
         if os.path.exists("/var/cache/pisi/%s.cache" % self.__class__.__name__.lower()):
-            self.__class__._the_instance.__dict__ = cPickle.load(file('/var/cache/pisi/%s.cache' % self.__class__.__name__.lower(), 'rb'))
+            self._instance().__dict__ = cPickle.load(file('/var/cache/pisi/%s.cache' % self.__class__.__name__.lower(), 'rb'))
             return True
         return False
 
@@ -46,17 +53,12 @@ class LazyDB(Singleton):
         if os.path.exists(cache_file):
             os.unlink(cache_file)
 
-    def reload(self):
-        self.cache_flush()
-        self.__init()
-
-    def close(self):
-        self.cache_save()
+    def invalidate(self):
+        self._delete()
 
     def __init(self):
         if not self.cache_load():
             self.init()
-            self.cache_save()
 
     def __getattr__(self, attr):
         if not attr == "__setstate__" and not self.initialized: