updates to service monitor. fix 500 on /api/info for empty listings

r2/r2/lib/jsontemplates.py

@@ -302,7 +302,7 @@ class RedditJsonTemplate(JsonTemplate):
 
 class PanestackJsonTemplate(JsonTemplate):
     def render(self, thing = None, *a, **kw):
-        res = [t.render() for t in thing.stack] if thing else []
+        res = [t.render() for t in thing.stack if t] if thing else []
         res = [x for x in res if x]
         if not res:
             return {}

r2/r2/templates/panestack.xml

@@ -21,5 +21,5 @@
 ################################################################################
 
 %for t in thing.stack:
-${t.render()}
+${t.render() if t else ''}
 %endfor

r2/supervise_watcher.py

@@ -298,15 +298,6 @@ def run_top(proc_ids = [], name = '', exe = "/usr/bin/top"):
 
     handle = subprocess.Popen(cmd, stdout = subprocess.PIPE,
                               stderr = subprocess.PIPE)
-    if handle.wait():
-        cmd = [exe, '-l', '1', '-p',
-               "^aaaaa ^nnnnnnnnn X X X X X X ^ccccc 0.0" +
-               " ^wwwwwwwwwww ^bbbbbbbbbbbbbbb"]
-        handle = subprocess.Popen(cmd, stdout = subprocess.PIPE,
-                                  stderr = subprocess.PIPE)
-        if handle.wait():
-            raise ValueError, "failed to run top"
-
     proc_ids = set(map(int, proc_ids))
     res = {}
     for line in handle.communicate()[0].split('\n'):