jobctrl.py: added %jobqueue for queueued system jobs

IPython/Extensions/jobctrl.py

@@ -41,8 +41,9 b' Now launch a new IPython prompt and kill the process:'
 (you don't need to specify PID for %kill if only one task is running)
 """                     
 
-from subprocess import Popen,PIPE
+from subprocess import *
 import os,shlex,sys,time
+import threading,Queue
 
 from IPython import genutils
 
@@ -71,15 +72,70 b' def startjob(job):'
     p.line = job
     return p
 
+class AsyncJobQ(threading.Thread):
+    def __init__(self):
+        threading.Thread.__init__(self)
+        self.q = Queue.Queue()
+        self.output = []
+        self.stop = False
+    def run(self):
+        while 1:
+            cmd,cwd = self.q.get()
+            if self.stop:
+                self.output.append("** Discarding: '%s' - %s" % (cmd,cwd))
+                continue
+            self.output.append("** Task started: '%s' - %s" % (cmd,cwd))
+            
+            p = Popen(cmd, shell=True, stdout=PIPE, stderr=STDOUT, cwd = cwd)
+            out = p.stdout.read()
+            self.output.append("** Task complete: '%s'\n" % cmd)
+            self.output.append(out)
+
+    def add(self,cmd):
+        self.q.put_nowait((cmd, os.getcwd()))
+        
+    def dumpoutput(self):
+        while self.output:
+            item = self.output.pop(0)
+            print item            
+
+_jobq = None
+
+def jobqueue_f(self, line):
+     
+    global _jobq
+    if not _jobq:
+        print "Starting jobqueue - do '&some_long_lasting_system_command' to enqueue"
+        _jobq = AsyncJobQ()
+        _jobq.setDaemon(True)
+        _jobq.start()
+        ip.jobq = _jobq.add
+        return
+    if line.strip() == 'stop':
+        print "Stopping and clearing jobqueue, %jobqueue start to start again"
+        _jobq.stop = True
+        return
+    if line.strip() == 'start':
+        _jobq.stop = False
+        return
+        
 def jobctrl_prefilter_f(self,line):    
     if line.startswith('&'):
         pre,fn,rest = self.split_user_input(line[1:])
         
         line = ip.IP.expand_aliases(fn,rest)
-        return '_ip.startjob(%s)' % genutils.make_quoted_expr(line)
+        if not _jobq:
+            return '_ip.startjob(%s)' % genutils.make_quoted_expr(line)
+        return '_ip.jobq(%s)' % genutils.make_quoted_expr(line)
 
     raise IPython.ipapi.TryNext
 
+def jobq_output_hook(self):
+    if not _jobq:
+        return
+    _jobq.dumpoutput()
+
+
 
 def job_list(ip):
     keys = ip.db.keys('tasks/*')
@@ -179,5 +235,6 b' def install():'
     ip.set_hook('shell_hook', jobctrl_shellcmd)
     ip.expose_magic('kill',magic_kill)
     ip.expose_magic('tasks',magic_tasks)
-    
+    ip.expose_magic('jobqueue',jobqueue_f)
+    ip.set_hook('pre_prompt_hook', jobq_output_hook) 
 install()