Mac/Lib/aetools.py

   1 """Tools for use in AppleEvent clients and servers.
   2
   3 pack(x) converts a Python object to an AEDesc object
   4 unpack(desc) does the reverse
   5
   6 packevent(event, parameters, attributes) sets params and attrs in an AEAppleEvent record
   7 unpackevent(event) returns the parameters and attributes from an AEAppleEvent record
   8
   9 Plus...  Lots of classes and routines that help representing AE objects,
  10 ranges, conditionals, logicals, etc., so you can write, e.g.:
  11
  12         x = Character(1, Document("foobar"))
  13
  14 and pack(x) will create an AE object reference equivalent to AppleScript's
  15
  16         character 1 of document "foobar"
  17
  18 Some of the stuff that appears to be exported from this module comes from other
  19 files: the pack stuff from aepack, the objects from aetypes.
  20
  21 """
  22
  23
  24 from types import *
  25 from Carbon import AE
  26 from Carbon import AppleEvents
  27 import MacOS
  28 import sys
  29
  30 from aetypes import *
  31 from aepack import pack, unpack, coerce, AEDescType
  32
  33 Error = 'aetools.Error'
  34
  35 # Special code to unpack an AppleEvent (which is *not* a disguised record!)
  36 # Note by Jack: No??!? If I read the docs correctly it *is*....
  37
  38 aekeywords = [
  39         'tran',
  40         'rtid',
  41         'evcl',
  42         'evid',
  43         'addr',
  44         'optk',
  45         'timo',
  46         'inte', # this attribute is read only - will be set in AESend
  47         'esrc', # this attribute is read only
  48         'miss', # this attribute is read only
  49         'from'  # new in 1.0.1
  50 ]
  51
  52 def missed(ae):
  53         try:
  54                 desc = ae.AEGetAttributeDesc('miss', 'keyw')
  55         except AE.Error, msg:
  56                 return None
  57         return desc.data
  58
  59 def unpackevent(ae):
  60         parameters = {}
  61         try:
  62                 dirobj = ae.AEGetParamDesc('----', '****')
  63         except AE.Error:
  64                 pass
  65         else:
  66                 parameters['----'] = unpack(dirobj)
  67                 del dirobj
  68         while 1:
  69                 key = missed(ae)
  70                 if not key: break
  71                 parameters[key] = unpack(ae.AEGetParamDesc(key, '****'))
  72         attributes = {}
  73         for key in aekeywords:
  74                 try:
  75                         desc = ae.AEGetAttributeDesc(key, '****')
  76                 except (AE.Error, MacOS.Error), msg:
  77                         if msg[0] != -1701 and msg[0] != -1704:
  78                                 raise sys.exc_type, sys.exc_value
  79                         continue
  80                 attributes[key] = unpack(desc)
  81         return parameters, attributes
  82
  83 def packevent(ae, parameters = {}, attributes = {}):
  84         for key, value in parameters.items():
  85                 ae.AEPutParamDesc(key, pack(value))
  86         for key, value in attributes.items():
  87                 ae.AEPutAttributeDesc(key, pack(value))
  88
  89 #
  90 # Support routine for automatically generated Suite interfaces
  91 # These routines are also useable for the reverse function.
  92 #
  93 def keysubst(arguments, keydict):
  94         """Replace long name keys by their 4-char counterparts, and check"""
  95         ok = keydict.values()
  96         for k in arguments.keys():
  97                 if keydict.has_key(k):
  98                         v = arguments[k]
  99                         del arguments[k]
 100                         arguments[keydict[k]] = v
 101                 elif k != '----' and k not in ok:
 102                         raise TypeError, 'Unknown keyword argument: %s'%k
 103
 104 def enumsubst(arguments, key, edict):
 105         """Substitute a single enum keyword argument, if it occurs"""
 106         if not arguments.has_key(key) or edict is None:
 107                 return
 108         v = arguments[key]
 109         ok = edict.values()
 110         if edict.has_key(v):
 111                 arguments[key] = edict[v]
 112         elif not v in ok:
 113                 raise TypeError, 'Unknown enumerator: %s'%v
 114
 115 def decodeerror(arguments):
 116         """Create the 'best' argument for a raise MacOS.Error"""
 117         errn = arguments['errn']
 118         err_a1 = errn
 119         if arguments.has_key('errs'):
 120                 err_a2 = arguments['errs']
 121         else:
 122                 err_a2 = MacOS.GetErrorString(errn)
 123         if arguments.has_key('erob'):
 124                 err_a3 = arguments['erob']
 125         else:
 126                 err_a3 = None
 127
 128         return (err_a1, err_a2, err_a3)
 129
 130 class TalkTo:
 131         """An AE connection to an application"""
 132         _signature = None       # Can be overridden by subclasses
 133
 134         def __init__(self, signature=None, start=0, timeout=0):
 135                 """Create a communication channel with a particular application.
 136
 137                 Addressing the application is done by specifying either a
 138                 4-byte signature, an AEDesc or an object that will __aepack__
 139                 to an AEDesc.
 140                 """
 141                 self.target_signature = None
 142                 if signature is None:
 143                         signature = self._signature
 144                 if type(signature) == AEDescType:
 145                         self.target = signature
 146                 elif type(signature) == InstanceType and hasattr(signature, '__aepack__'):
 147                         self.target = signature.__aepack__()
 148                 elif type(signature) == StringType and len(signature) == 4:
 149                         self.target = AE.AECreateDesc(AppleEvents.typeApplSignature, signature)
 150                         self.target_signature = signature
 151                 else:
 152                         raise TypeError, "signature should be 4-char string or AEDesc"
 153                 self.send_flags = AppleEvents.kAEWaitReply
 154                 self.send_priority = AppleEvents.kAENormalPriority
 155                 if timeout:
 156                         self.send_timeout = timeout
 157                 else:
 158                         self.send_timeout = AppleEvents.kAEDefaultTimeout
 159                 if start:
 160                         self._start()
 161
 162         def _start(self):
 163                 """Start the application, if it is not running yet"""
 164                 try:
 165                         self.send('ascr', 'noop')
 166                 except AE.Error:
 167                         _launch(self.target_signature)
 168
 169         def start(self):
 170                 """Deprecated, used _start()"""
 171                 self._start()
 172
 173         def newevent(self, code, subcode, parameters = {}, attributes = {}):
 174                 """Create a complete structure for an apple event"""
 175
 176                 event = AE.AECreateAppleEvent(code, subcode, self.target,
 177                           AppleEvents.kAutoGenerateReturnID, AppleEvents.kAnyTransactionID)
 178                 packevent(event, parameters, attributes)
 179                 return event
 180
 181         def sendevent(self, event):
 182                 """Send a pre-created appleevent, await the reply and unpack it"""
 183
 184                 reply = event.AESend(self.send_flags, self.send_priority,
 185                                           self.send_timeout)
 186                 parameters, attributes = unpackevent(reply)
 187                 return reply, parameters, attributes
 188
 189         def send(self, code, subcode, parameters = {}, attributes = {}):
 190                 """Send an appleevent given code/subcode/pars/attrs and unpack the reply"""
 191                 return self.sendevent(self.newevent(code, subcode, parameters, attributes))
 192
 193         #
 194         # The following events are somehow "standard" and don't seem to appear in any
 195         # suite...
 196         #
 197         def activate(self):
 198                 """Send 'activate' command"""
 199                 self.send('misc', 'actv')
 200
 201         def _get(self, _object, as=None, _attributes={}):
 202                 """_get: get data from an object
 203                 Required argument: the object
 204                 Keyword argument _attributes: AppleEvent attribute dictionary
 205                 Returns: the data
 206                 """
 207                 _code = 'core'
 208                 _subcode = 'getd'
 209
 210                 _arguments = {'----':_object}
 211                 if as:
 212                         _arguments['rtyp'] = mktype(as)
 213
 214                 _reply, _arguments, _attributes = self.send(_code, _subcode,
 215                                 _arguments, _attributes)
 216                 if _arguments.has_key('errn'):
 217                         raise Error, decodeerror(_arguments)
 218
 219                 if _arguments.has_key('----'):
 220                         return _arguments['----']
 221
 222 # Tiny Finder class, for local use only
 223
 224 class _miniFinder(TalkTo):
 225         def open(self, _object, _attributes={}, **_arguments):
 226                 """open: Open the specified object(s)
 227                 Required argument: list of objects to open
 228                 Keyword argument _attributes: AppleEvent attribute dictionary
 229                 """
 230                 _code = 'aevt'
 231                 _subcode = 'odoc'
 232
 233                 if _arguments: raise TypeError, 'No optional args expected'
 234                 _arguments['----'] = _object
 235
 236
 237                 _reply, _arguments, _attributes = self.send(_code, _subcode,
 238                                 _arguments, _attributes)
 239                 if _arguments.has_key('errn'):
 240                         raise Error, decodeerror(_arguments)
 241                 # XXXX Optionally decode result
 242                 if _arguments.has_key('----'):
 243                         return _arguments['----']
 244 #pass
 245
 246 _finder = _miniFinder('MACS')
 247
 248 def _launch(appfile):
 249         """Open a file thru the finder. Specify file by name or fsspec"""
 250         _finder.open(_application_file(('ID  ', appfile)))
 251
 252
 253 class _application_file(ComponentItem):
 254         """application file - An application's file on disk"""
 255         want = 'appf'
 256
 257 _application_file._propdict = {
 258 }
 259 _application_file._elemdict = {
 260 }
 261
 262 # Test program
 263 # XXXX Should test more, really...
 264
 265 def test():
 266         target = AE.AECreateDesc('sign', 'quil')
 267         ae = AE.AECreateAppleEvent('aevt', 'oapp', target, -1, 0)
 268         print unpackevent(ae)
 269         raw_input(":")
 270         ae = AE.AECreateAppleEvent('core', 'getd', target, -1, 0)
 271         obj = Character(2, Word(1, Document(1)))
 272         print obj
 273         print repr(obj)
 274         packevent(ae, {'----': obj})
 275         params, attrs = unpackevent(ae)
 276         print params['----']
 277         raw_input(":")
 278
 279 if __name__ == '__main__':
 280         test()
 281         sys.exit(1)