Source Code for Module osh.builtins

 1  # osh 
 2  # Copyright (C) Jack Orenstein <jao@geophile.com> 
 3  # 
 4  # This program is free software; you can redistribute it and/or modify 
 5  # it under the terms of the GNU General Public License as published by 
 6  # the Free Software Foundation; either version 2 of the License, or 
 7  # (at your option) any later version. 
 8  # 
 9  # This program is distributed in the hope that it will be useful, 
10  # but WITHOUT ANY WARRANTY; without even the implied warranty of 
11  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
12  # GNU General Public License for more details. 
13  # 
14  # You should have received a copy of the GNU General Public License 
15  # along with this program; if not, write to the Free Software 
16  # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 
17   
18  """This module contains miscellaneous functions builtin to osh. 
19  See also the C{osh.process} module for other builtins. 
20  """ 
21   
22  import config 
23  from core import add_to_namespace 
24  from cluster import cluster_named 
25   
26  #---------------------------------------------------------------------- 
27   
28  # processes 
29   
30  from process import processes 
31   
32  add_to_namespace('processes', processes) 
33   
34  #---------------------------------------------------------------------- 
35   
36  # ifelse 
37   
38 -def ifelse(predicate, if_true, if_false): 
39      """Returns C{if_true} if C{predicate} is true, C{if_false} otherwise. 
40      Both C{if_true} and C{if_false} are evaluated unconditionally. 
41      (This function is provided because the Python equivalent, the if expression, 
42      is not present prior to release 2.5.) 
43      """ 
44      if predicate: 
45          return if_true 
46      else: 
47          return if_false 
48   
49  add_to_namespace('ifelse', ifelse) 
50   
51  #---------------------------------------------------------------------- 
52   
53  # hosts 
54   
55 -def hosts(cluster_name): 
56      """Returns the value of C{cluster_name}'s C{hosts} configuration value, 
57      as specified in C{.oshrc}. Returns a map containing entries 
58      in which the key is the node's name, and the value is the node's 
59      IP address or DNS name. 
60      """ 
61      map = {} 
62      cluster = cluster_named(cluster_name) 
63      if cluster: 
64          for host in cluster.hosts: 
65              map[host.name] = host.address 
66          return map 
67      else: 
68          return None 
69   
70  add_to_namespace('hosts', hosts) 
71