ctlmod.py

   1 # Erebus IRC bot - Author: John Runyon
   2 # vim: fileencoding=utf-8
   3 # module loading/unloading/tracking code
   4
   5 from __future__ import print_function
   6
   7 import sys, time, importlib, traceback
   8 import modlib
   9
  10 if sys.version_info.major >= 3:
  11         from importlib import reload # reload is only available as a global in Py2, only in importlib in Py3
  12 else:
  13         importlib.invalidate_caches = lambda: None # invalidate_caches doesn't exist in Py2
  14
  15 modules = {}
  16 dependents = {}
  17 #dependents[modname] = [list of modules which depend on modname]
  18
  19 def isloaded(modname): return modname in modules
  20 def modhas(modname, attname): return getattr(modules[modname], attname, None) is not None
  21
  22 def load(parent, modname, dependent=False):
  23         """Wrapper to call _load and print the return value."""
  24         if dependent:
  25                 print("(Loading dependency %s..." % (modname), end=' ')
  26         else:
  27                 print("%09.3f [MOD] [?] Loading %s..." % (time.time() % 100000, modname), end=' ')
  28         modstatus = _load(parent, modname, dependent)
  29         if not modstatus:
  30                 if dependent:
  31                         print("failed: %s)" % (modstatus), end=' ')
  32                 else:
  33                         print("failed: %s." % (modstatus))
  34                         if isinstance(modstatus, modlib.error) and isinstance(modstatus.errormsg, BaseException):
  35                                 traceback.print_exception(modstatus.errormsg)
  36         elif modstatus == True:
  37                 if dependent:
  38                         print("OK)", end=' ')
  39                 else:
  40                         print("OK.")
  41         else:
  42                 if dependent:
  43                         print("OK: %s)" % (modstatus), end=' ')
  44                 else:
  45                         print("OK: %s." % (modstatus))
  46         return modstatus
  47
  48 def _load(parent, modname, dependent=False):
  49         """Load and return the new status of the module."""
  50         successstatus = []
  51         if not isloaded(modname):
  52                 importlib.invalidate_caches()
  53                 try:
  54                         mod = importlib.import_module('modules.'+modname)
  55                         reload(mod) #in case it's been previously loaded.
  56                 except Exception as e:
  57                         return modlib.error(e)
  58
  59
  60                 if not hasattr(mod, 'modinfo'):
  61                         return modlib.error('no modinfo')
  62
  63                 if parent.APIVERSION not in mod.modinfo['compatible']:
  64                         return modlib.error('API-incompatible')
  65
  66                 modules[modname] = mod
  67                 dependents[modname] = []
  68
  69                 for dep in mod.modinfo['depends']:
  70                         if bool(int(parent.cfg.get('autoloads', dep, default=1))):
  71                                 if dep not in modules:
  72                                         depret = load(parent, dep, dependent=True)
  73                                         if depret is not None and not depret:
  74                                                 return depret
  75                         else:
  76                                 return modlib.error("dependent %s disabled" % (dep))
  77                         dependents[dep].append(modname)
  78
  79                 for dep in mod.modinfo['softdeps']:
  80                         if bool(int(parent.cfg.get('autoloads', dep, default=1))):
  81                                 if dep not in modules:
  82                                         depret = load(parent, dep, dependent=True)
  83                                         if depret is not None and not depret:
  84                                                 successstatus.append("softdep %s failed" % (dep))
  85                         else:
  86                                 successstatus.append("softdep %s disabled" % (dep))
  87                         #swallow errors loading - softdeps are preferred, not required
  88
  89
  90                 try:
  91                         ret = mod.modstart(parent)
  92                 except Exception as e:
  93                         return modlib.error(e)
  94                 if ret is None:
  95                         ret = True
  96                 if not ret:
  97                         del modules[modname]
  98                         del dependents[modname]
  99                         for dep in mod.modinfo['depends']:
 100                                 dependents[dep].remove(modname)
 101
 102                 successstatus = ';'.join(successstatus)
 103                 if len(successstatus) > 0 and ret:
 104                         if ret == True:
 105                                 return successstatus
 106                         else:
 107                                 return "%s (%s)" % (ret, successstatus)
 108                 else:
 109                         return ret
 110         else: #if not isloaded...else:
 111                 return modlib.error('already loaded')
 112
 113 def unload(parent, modname):
 114         if isloaded(modname):
 115                 for dependent in dependents[modname]:
 116                         unload(parent, dependent)
 117                 for dep in modules[modname].modinfo['depends']:
 118                         dependents[dep].remove(modname)
 119                 ret = modules[modname].modstop(parent)
 120                 del modules[modname]
 121                 return ret
 122         else:
 123                 return modlib.error('already unloaded')
 124
 125 def reloadmod(parent, modname):
 126         if isloaded(modname):
 127                 if modhas(modname, 'modrestart'): modules[modname].modrestart(parent)
 128                 else: modules[modname].modstop(parent)
 129
 130                 try:
 131                         reload(modules[modname])
 132                 except BaseException as e:
 133                         return modlib.error(e)
 134
 135                 if modhas(modname, 'modrestarted'): ret = modules[modname].modrestarted(parent)
 136                 else: ret = modules[modname].modstart(parent)
 137
 138                 return ret
 139         else:
 140                 return load(parent, modname)
 141
 142
 143 def loadall(parent, modlist):
 144         for m in modlist: load(parent, m)
 145 def unloadall(parent, modlist):
 146         for m in modlist: unload(parent, m)
 147 def reloadall(parent, modlist):
 148         for m in modlist: reloadmod(parent, m)