Pass Me2Me config via stdin.

remoting/tools/me2me_virtual_host.py

Index: remoting/tools/me2me_virtual_host.py
diff --git a/remoting/tools/me2me_virtual_host.py b/remoting/tools/me2me_virtual_host.py
index 53a3118bc1602be68594b5668b48051abd2d2414..b159facac947824fa9c9e18550b28af7964fe561 100755
--- a/remoting/tools/me2me_virtual_host.py
+++ b/remoting/tools/me2me_virtual_host.py
@@ -288,12 +288,14 @@ class Desktop:
 
   def launch_host(self, host_config):
     # Start remoting host
-    args = [locate_executable(HOST_BINARY_NAME),
-            "--host-config=%s" % (host_config.path)]
-    self.host_proc = subprocess.Popen(args, env=self.child_env)
+    args = [locate_executable(HOST_BINARY_NAME), "--host-config=/dev/stdin"]
+    self.host_proc = subprocess.Popen(args, env=self.child_env,
+                                      stdin=subprocess.PIPE)
     logging.info(args)
     if not self.host_proc.pid:
       raise Exception("Could not start Chrome Remote Desktop host")
+    self.host_proc.stdin.write(json.dumps(host_config.data))
+    self.host_proc.stdin.close()
 
 
 class PidFile:
@@ -515,19 +517,27 @@ def cleanup():
   g_desktops = []
 
 
-def reload_config():
-  for desktop in g_desktops:
-    if desktop.host_proc:
-      desktop.host_proc.send_signal(signal.SIGHUP)
+class SignalHandler:
+  """Reload the config file on SIGHUP. Since we pass the configuration to the
+  host processes via stdin, they can't reload it, so terminate them. They will
+  be relaunched automatically with the new config."""
 
+  def __init__(self, host_config):
+    self.host_config = host_config
 
-def signal_handler(signum, _stackframe):
-  if signum == signal.SIGHUP:
-    logging.info("SIGHUP caught, reloading configuration.")
-    reload_config()
-  else:
-    # Exit cleanly so the atexit handler, cleanup(), gets called.
-    raise SystemExit
+  def __call__(self, signum, _stackframe):
+    if signum == signal.SIGHUP:
+      logging.info("SIGHUP caught, restarting host.")
+      self.reload_config()
+    else:
+      # Exit cleanly so the atexit handler, cleanup(), gets called.
+      raise SystemExit
+
+  def reload_config(self):

[Sergey Ulanov, 2012/09/04 22:01:48]

This method is not used outside of this class, so it should be private. call it
_reload_config()?

[Jamie, 2012/09/05 21:15:38]

I just got rid of the function. There was no real need for it to be factored
out.

+    self.host_config.load()
+    for desktop in g_desktops:
+      if desktop.host_proc:
+        desktop.host_proc.send_signal(signal.SIGTERM)
 
 
 def relaunch_self():
@@ -642,15 +652,15 @@ Web Store: https://chrome.google.com/remotedesktop"""
 
   atexit.register(cleanup)
 
-  for s in [signal.SIGHUP, signal.SIGINT, signal.SIGTERM, signal.SIGUSR1]:
-    signal.signal(s, signal_handler)
+  config_filename = os.path.join(CONFIG_DIR, "host#%s.json" % host_hash)
+  host_config = Config(config_filename)
 
-  # Ensure full path to config directory exists.
-  if not os.path.exists(CONFIG_DIR):
-    os.makedirs(CONFIG_DIR, mode=0700)
+  for s in [signal.SIGHUP, signal.SIGINT, signal.SIGTERM, signal.SIGUSR1]:
+    signal.signal(s, SignalHandler(host_config))
 
-  host_config = Config(os.path.join(CONFIG_DIR, "host#%s.json" % host_hash))
-  host_config.load()
+  if (not host_config.load()):
+    print >> sys.stderr, "Failed to load " + config_filename

[Lambros, 2012/09/05 16:35:54]

logging.error() is preferred for printing error messages.  We should eventually
fix other instances to be more consistent.  Now I'm thinking about it, we really
should be using logging.fatal() whenever the error is serious enough to exit the
program.  For this CL, I think "logging.error()" is OK for now, but do whatever
you think's best.

+    return 1
 
   auth = Authentication()
   auth_config_valid = auth.copy_from(host_config)