3 # Copyright (c) 2016 Cisco and/or its affiliates.
4 # Licensed under the Apache License, Version 2.0 (the "License");
5 # you may not use this file except in compliance with the License.
6 # You may obtain a copy of the License at:
8 # http://www.apache.org/licenses/LICENSE-2.0
10 # Unless required by applicable law or agreed to in writing, software
11 # distributed under the License is distributed on an "AS IS" BASIS,
12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 # See the License for the specific language governing permissions and
14 # limitations under the License.
17 from __future__ import print_function
18 import sys, os, logging, collections, struct, json, threading
19 logging.basicConfig(level=logging.DEBUG)
22 def eprint(*args, **kwargs):
23 print(*args, file=sys.stderr, **kwargs)
26 def __init__(self, apifiles):
30 self.buffersize = 10000
31 self.connected = False
32 self.header = struct.Struct('>HI')
38 self.apifile.append(file)
39 with open(file) as apidef_file:
40 api = json.load(apidef_file)
41 for t in api['types']:
42 self.add_type(t[0], t[1:])
44 for m in api['messages']:
45 self.add_message(m[0], m[1:])
48 if not 'control_ping' in self.messages:
49 raise ValueError(1, 'Error in JSON message definitions')
52 class ContextId(object):
58 get_context = ContextId()
61 print('Connected') if self.connected else print('Not Connected')
62 print('Read API definitions from', self.apifile)
64 def __struct (self, t, n = None, e = 0, vl = None):
65 base_types = { 'u8' : 'B',
78 return struct.Struct('>' + str(e) + 's')
80 # Fixed array of base type
81 return [e, struct.Struct('>' + base_types[t])]
83 # Variable length array
84 return [vl, struct.Struct('>s')] if t == 'u8' else [vl, struct.Struct('>' + base_types[t])]
86 return struct.Struct('>' + base_types[t])
88 if t in self.messages:
89 ### Return a list in case of array ###
91 return [e, lambda self, encode, buf, offset, args: (
92 self.__struct_type(encode, self.messages[t], buf, offset, args)
95 return [vl, lambda self, encode, buf, offset, args: (
96 self.__struct_type(encode, self.messages[t], buf, offset, args)
98 return lambda self, encode, buf, offset, args: (
99 self.__struct_type(encode, self.messages[t], buf, offset, args)
104 def __struct_type(self, encode, msgdef, buf, offset, kwargs):
106 return self.__struct_type_encode(msgdef, buf, offset, kwargs)
108 return self.__struct_type_decode(msgdef, buf, offset)
110 def __struct_type_encode(self, msgdef, buf, offset, kwargs):
115 if k not in msgdef['args']:
116 raise ValueError(1, 'Invalid field-name in message call ' + k)
118 for k,v in msgdef['args'].iteritems():
129 size += v[1](self, True, buf, off + size,
137 buf[off:off + l] = bytearray(kwargs[k])
142 v[1].pack_into(buf, off + size, i)
146 size = v(self, True, buf, off, kwargs[k])
148 v.pack_into(buf, off, kwargs[k])
151 size = v.size if not type(v) is list else 0
153 return off + size - offset
156 def __getitem__(self, name):
157 if name in self.messages:
158 return self.messages[name]
161 def encode(self, msgdef, kwargs):
162 # Make suitably large buffer
163 buf = bytearray(self.buffersize)
165 size = self.__struct_type(True, msgdef, buf, offset, kwargs)
166 return buf[:offset + size]
168 def decode(self, msgdef, buf):
169 return self.__struct_type(False, msgdef, buf, 0, None)[1]
171 def __struct_type_decode(self, msgdef, buf, offset):
175 for k,v in msgdef['args'].iteritems():
179 if callable(v[1]): # compound type
181 if v[0] in msgdef['args']: # vla
187 (s,l) = v[1](self, False, buf, off + size, None)
194 res.append(buf[off:off + size])
203 lst.append(v[1].unpack_from(buf, off + size)[0])
207 (s,l) = v(self, False, buf, off, None)
211 res.append(v.unpack_from(buf, off)[0])
214 return off + size - offset, msgdef['return_tuple']._make(res)
216 def ret_tup(self, name):
217 if name in self.messages and 'return_tuple' in self.messages[name]:
218 return self.messages[name]['return_tuple']
221 def add_message(self, name, msgdef):
222 if name in self.messages:
223 raise ValueError('Duplicate message name: ' + name)
225 args = collections.OrderedDict()
226 argtypes = collections.OrderedDict()
230 if type(f) is dict and 'crc' in f:
231 msg['crc'] = f['crc']
235 args[field_name] = self.__struct(*f)
236 argtypes[field_name] = field_type
237 fields.append(field_name)
238 msg['return_tuple'] = collections.namedtuple(name, fields,
240 self.messages[name] = msg
241 self.messages[name]['args'] = args
242 self.messages[name]['argtypes'] = argtypes
243 return self.messages[name]
245 def add_type(self, name, typedef):
246 self.add_message('vl_api_' + name + '_t', typedef)
248 def make_function(self, name, i, msgdef, multipart, async):
250 f = lambda **kwargs: (self._call_vpp_async(i, msgdef, multipart, **kwargs))
252 f = lambda **kwargs: (self._call_vpp(i, msgdef, multipart, **kwargs))
253 args = self.messages[name]['args']
254 argtypes = self.messages[name]['argtypes']
255 f.__name__ = str(name)
256 f.__doc__ = ", ".join(["%s %s" % (argtypes[k], k) for k in args.keys()])
259 def _register_functions(self, async=False):
260 self.id_names = [None] * (self.vpp_dictionary_maxid + 1)
261 self.id_msgdef = [None] * (self.vpp_dictionary_maxid + 1)
262 for name, msgdef in self.messages.iteritems():
263 if name in self.vpp_dictionary:
264 if self.messages[name]['crc'] != self.vpp_dictionary[name]['crc']:
265 raise ValueError(3, 'Failed CRC checksum ' + name +
266 ' ' + self.messages[name]['crc'] +
267 ' ' + self.vpp_dictionary[name]['crc'])
268 i = self.vpp_dictionary[name]['id']
269 self.id_msgdef[i] = msgdef
270 self.id_names[i] = name
271 multipart = True if name.find('_dump') > 0 else False
272 setattr(self, name, self.make_function(name, i, msgdef, multipart, async))
274 def _write (self, buf):
275 if not self.connected:
276 raise IOError(1, 'Not connected')
277 return vpp_api.write(str(buf))
279 def _load_dictionary(self):
280 self.vpp_dictionary = {}
281 self.vpp_dictionary_maxid = 0
282 d = vpp_api.msg_table()
285 raise IOError(3, 'Cannot get VPP API dictionary')
287 name, crc = n.rsplit('_', 1)
289 self.vpp_dictionary[name] = { 'id' : i, 'crc' : crc }
290 self.vpp_dictionary_maxid = max(self.vpp_dictionary_maxid, i)
292 def connect(self, name, chroot_prefix = None, async = False):
293 msg_handler = self.msg_handler if not async else self.msg_handler_async
294 if not chroot_prefix:
295 rv = vpp_api.connect(name, msg_handler)
297 rv = vpp_api.connect(name, msg_handler, chroot_prefix)
300 raise IOError(2, 'Connect failed')
301 self.connected = True
303 self._load_dictionary()
304 self._register_functions(async=async)
306 # Initialise control ping
307 self.control_ping_index = self.vpp_dictionary['control_ping']['id']
308 self.control_ping_msgdef = self.messages['control_ping']
310 def disconnect(self):
311 rv = vpp_api.disconnect()
314 def results_wait(self, context):
315 return (self.results[context]['e'].wait(self.timeout))
317 def results_prepare(self, context):
318 self.results[context] = {}
319 self.results[context]['e'] = threading.Event()
320 self.results[context]['e'].clear()
321 self.results[context]['r'] = []
323 def results_clean(self, context):
324 del self.results[context]
326 def msg_handler(self, msg):
328 eprint('vpp_api.read failed')
331 i, ci = self.header.unpack_from(msg, 0)
332 if self.id_names[i] == 'rx_thread_exit':
336 # Decode message and returns a tuple.
338 msgdef = self.id_msgdef[i]
340 raise IOError(2, 'Reply message undefined')
342 r = self.decode(msgdef, msg)
343 if 'context' in r._asdict():
347 msgname = type(r).__name__
350 # XXX: Call provided callback for event
351 # Are we guaranteed to not get an event during processing of other messages?
352 # How to differentiate what's a callback message and what not? Context = 0?
354 #if not is_waiting_for_reply():
355 if r.context == 0 and self.event_callback:
356 self.event_callback(msgname, r)
360 # Collect results until control ping
362 if msgname == 'control_ping_reply':
363 self.results[context]['e'].set()
366 if not context in self.results:
367 eprint('Not expecting results for this context', context, r)
370 if 'm' in self.results[context]:
371 self.results[context]['r'].append(r)
374 self.results[context]['r'] = r
375 self.results[context]['e'].set()
377 def msg_handler_async(self, msg):
379 eprint('vpp_api.read failed')
382 i, ci = self.header.unpack_from(msg, 0)
383 if self.id_names[i] == 'rx_thread_exit':
387 # Decode message and returns a tuple.
389 msgdef = self.id_msgdef[i]
391 raise IOError(2, 'Reply message undefined')
393 r = self.decode(msgdef, msg)
394 msgname = type(r).__name__
396 self.event_callback(msgname, r)
398 def _control_ping(self, context):
399 self._write(self.encode(self.control_ping_msgdef,
400 { '_vl_msg_id' : self.control_ping_index,
401 'context' : context}))
403 def _call_vpp(self, i, msgdef, multipart, **kwargs):
404 if not 'context' in kwargs:
405 context = self.get_context()
406 kwargs['context'] = context
408 context = kwargs['context']
409 kwargs['_vl_msg_id'] = i
410 b = self.encode(msgdef, kwargs)
412 self.results_prepare(context)
416 self.results[context]['m'] = True
417 self._control_ping(context)
418 self.results_wait(context)
419 r = self.results[context]['r']
420 self.results_clean(context)
423 def _call_vpp_async(self, i, msgdef, multipart, **kwargs):
424 if not 'context' in kwargs:
425 context = self.get_context()
426 kwargs['context'] = context
428 context = kwargs['context']
429 kwargs['_vl_msg_id'] = i
430 b = self.encode(msgdef, kwargs)
434 def register_event_callback(self, callback):
435 self.event_callback = callback