Add --named-screen option

herd/herd.py

@@ -137,6 +137,7 @@ def run(local_file, remote_file, hosts):
 
 def transfer(host, local_file, remote_target, retry=0):
     rp = opts['remote_path']
+    named_screen = opts['named_screen']
     file_name = os.path.basename(local_file)
     remote_file = '%s/%s' % (rp, file_name)
     if ssh(host, 'test -d %s/BitTornado' % rp) != 0:
@@ -151,13 +152,17 @@ def transfer(host, local_file, remote_target, retry=0):
         rp,
         remote_file,
         remote_target)
+    if named_screen:
+        command = 'screen -S %s -- %s' % (named_screen, command)
     log.info("running \"%s\" on %s", command, host)
     result = ssh(host, command)
     if result == 0:
         cmd = 'python %s/herd.py %s %s --seed True' % (
             rp,
             remote_file,
             remote_target)
+        if named_screen:
+            cmd = 'screen -S %s -- %s' % (named_screen, cmd)
         s = threading.Thread(target=ssh, args=(host, cmd,))
         s.daemon = True
         s.start()
@@ -166,7 +171,7 @@ def transfer(host, local_file, remote_target, retry=0):
         while retry != 0:
             retry = retry - 1
             log.info("retrying on %s" % host)
-            transfer(host, local_file, remote_target, 0)
+            transfer(host, local_file, remote_target, 0, named_screen)
     return host
 
 
@@ -201,6 +206,11 @@ def mktorrent(file_name, tracker):
     return torrent_file[1]
 
 
+def screen_exists():
+    return_code = subprocess.call(['which', 'screen'])
+    return_code == 0
+
+
 def track():
     bttrack.track(["--dfile", opts['data_file'], "--port", opts['port']])
 
@@ -239,13 +249,17 @@ def herdmain():
 
 def run_with_opts(local_file, remote_file, hosts='', retry=0, port=8998,
                   remote_path='/tmp/herd', data_file='./data',
-                  log_dir='/tmp/herd', hostlist=False):
+                  log_dir='/tmp/herd', hostlist=False, named_screen=''):
     """Can include herd into existing python easier."""
     global opts
     opts['local-file'] = local_file
     opts['remote-file'] = remote_file
     opts['hosts'] = hosts
     opts['retry'] = retry
+    if screen_exists:
+        opts['named_screen'] = named_screen
+    else:
+        opts['named_screen'] = False
     opts['port'] = get_random_open_port(port)
     opts['remote_path'] = remote_path
     opts['data_file'] = data_file
@@ -274,6 +288,10 @@ def entry_point():
                         help="Number of times to retry in case of failure. " +
                         "Use -1 to make it retry forever (not recommended)")
 
+    parser.add_argument('--named-screen',
+                        default='',
+                        help="If value is given, runs murder inside named screen for easy cleanup")
+
     parser.add_argument('--port',
                         default=8998,
                         help="Port number to run the tracker on. Port range " +
@@ -301,6 +319,9 @@ def entry_point():
 
     opts = vars(parser.parse_args())
 
+    if not screen_exists():
+        opts['named_screen'] = False
+
     # potentially select a random port
     opts['port'] = get_random_open_port(opts['port'])