From: Greg Price <price@mit.edu>
Date: Wed, 29 Oct 2008 04:44:44 +0000 (-0400)
Subject: factor a bit of code out of the mondo invirt.config.load()
X-Git-Tag: 0.0.2~3
X-Git-Url: http://xvm.mit.edu/gitweb/invirt/packages/invirt-base.git/commitdiff_plain/1eff7d13e6578fc1e4da25cd3e78c126ebe62ebd

factor a bit of code out of the mondo invirt.config.load()

svn path=/trunk/packages/invirt-base/; revision=1421
---

diff --git a/python/invirt/config.py b/python/invirt/config.py
index 0e906d5..7c2b805 100644
--- a/python/invirt/config.py
+++ b/python/invirt/config.py
@@ -5,11 +5,22 @@ from invirt.common import *
 from os import rename
 from os.path import getmtime
 from contextlib import closing
+import yaml
+
+try:    loader = yaml.CSafeLoader
+except: loader = yaml.SafeLoader
 
 src_path   = '/etc/invirt/master.yaml'
 cache_path = '/var/lib/invirt/cache.json'
 lock_path  = '/var/lib/invirt/cache.lock'
 
+def load_master():
+    with closing(file(src_path)) as f:
+        return yaml.load(f, loader)
+
+def get_src_mtime():
+    return getmtime(src_path)
+
 def load(force_refresh = False):
     """
     Try loading the configuration from the faster-to-load JSON cache at
@@ -25,7 +36,7 @@ def load(force_refresh = False):
     if force_refresh:
         do_refresh = True
     else:
-        src_mtime = getmtime(src_path)
+        src_mtime = get_src_mtime()
         try:            cache_mtime = getmtime(cache_path)
         except OSError: do_refresh  = True
         else:           do_refresh  = src_mtime + 1 >= cache_mtime
@@ -66,21 +77,16 @@ def load(force_refresh = False):
         # is interleaved).  The final atomic rename is to keep this
         # transactionally isolated from the above cache read.  If we fail to
         # acquire the lock, just try to load the master configuration.
-        import yaml
-        try:    loader = yaml.CSafeLoader
-        except: loader = yaml.SafeLoader
         try:
             with lock_file(lock_path):
-                with closing(file(src_path)) as f:
-                    ns.cfg = yaml.load(f, loader)
+                ns.cfg = load_master()
                 try: 
                     with closing(file(cache_path + '.tmp', 'w')) as f:
                         f.write(json.write(ns.cfg))
                 except: pass # silent failure
                 else: rename(cache_path + '.tmp', cache_path)
         except IOError:
-            with closing(file(src_path)) as f:
-                ns.cfg = yaml.load(f, loader)
+            ns.cfg = load_master()
     return ns.cfg
 
 dicts = load()