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
   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         elif modstatus == True:
  35                 if dependent:
  36                         print("OK)", end=' ')
  37                 else:
  38                         print("OK.")
  39         else:
  40                 if dependent:
  41                         print("OK: %s)" % (modstatus), end=' ')
  42                 else:
  43                         print("OK: %s." % (modstatus))
  44         return modstatus
  45
  46 def _load(parent, modname, dependent=False):
  47         """Load and return the new status of the module."""
  48         successstatus = []
  49         if not isloaded(modname):
  50                 importlib.invalidate_caches()
  51                 try:
  52                         mod = importlib.import_module('modules.'+modname)
  53                         reload(mod) #in case it's been previously loaded.
  54                 except Exception as e:
  55                         return modlib.error(e)
  56
  57
  58                 if not hasattr(mod, 'modinfo'):
  59                         return modlib.error('no modinfo')
  60
  61                 if parent.APIVERSION not in mod.modinfo['compatible']:
  62                         return modlib.error('API-incompatible')
  63
  64                 modules[modname] = mod
  65                 dependents[modname] = []
  66
  67                 for dep in mod.modinfo['depends']:
  68                         if bool(int(parent.cfg.get('autoloads', dep, default=1))):
  69                                 if dep not in modules:
  70                                         depret = load(parent, dep, dependent=True)
  71                                         if depret is not None and not depret:
  72                                                 return depret
  73                         else:
  74                                 return modlib.error("dependent %s disabled" % (dep))
  75                         dependents[dep].append(modname)
  76
  77                 for dep in mod.modinfo['softdeps']:
  78                         if bool(int(parent.cfg.get('autoloads', dep, default=1))):
  79                                 if dep not in modules:
  80                                         depret = load(parent, dep, dependent=True)
  81                                         if depret is not None:
  82                                                 if not depret:
  83                                                         successstatus.append("softdep %s failed" % (dep))
  84                         else:
  85                                 successstatus.append("softdep %s disabled" % (dep))
  86                         #swallow errors loading - softdeps are preferred, not required
  87
  88
  89                 ret = mod.modstart(parent)
  90                 if ret is None:
  91                         ret = True
  92                 if not ret:
  93                         del modules[modname]
  94                         del dependents[modname]
  95                         for dep in mod.modinfo['depends']:
  96                                 dependents[dep].remove(modname)
  97
  98                 successstatus = ';'.join(successstatus)
  99                 if len(successstatus) > 0 and ret:
 100                         if ret == True:
 101                                 return successstatus
 102                         else:
 103                                 return "%s (%s)" % (ret, successstatus)
 104                 else:
 105                         return ret
 106         else: #if not isloaded...else:
 107                 return modlib.error('already loaded')
 108
 109 def unload(parent, modname):
 110         if isloaded(modname):
 111                 for dependent in dependents[modname]:
 112                         unload(parent, dependent)
 113                 for dep in modules[modname].modinfo['depends']:
 114                         dependents[dep].remove(modname)
 115                 ret = modules[modname].modstop(parent)
 116                 del modules[modname]
 117                 return ret
 118         else:
 119                 return modlib.error('already unloaded')
 120
 121 def reloadmod(parent, modname):
 122         if isloaded(modname):
 123                 if modhas(modname, 'modrestart'): modules[modname].modrestart(parent)
 124                 else: modules[modname].modstop(parent)
 125
 126                 try:
 127                         reload(modules[modname])
 128                 except BaseException as e:
 129                         return modlib.error(e)
 130
 131                 if modhas(modname, 'modrestarted'): ret = modules[modname].modrestarted(parent)
 132                 else: ret = modules[modname].modstart(parent)
 133
 134                 return ret
 135         else:
 136                 return load(parent, modname)
 137
 138
 139 def loadall(parent, modlist):
 140         for m in modlist: load(parent, m)
 141 def unloadall(parent, modlist):
 142         for m in modlist: unload(parent, m)
 143 def reloadall(parent, modlist):
 144         for m in modlist: reloadmod(parent, m)