#
from __future__ import print_function
-import sys, os, logging, collections, struct, json, threading, glob
-logging.basicConfig(level=logging.DEBUG)
-import vpp_api
+from __future__ import absolute_import
+import sys
+import os
+import logging
+import collections
+import struct
+import json
+import threading
+import fnmatch
+import weakref
+import atexit
+from . vpp_serializer import VPPType, VPPEnumType, VPPUnionType, BaseTypes
+from . vpp_serializer import VPPMessage, vpp_get_type, VPPTypeAlias
+from . vpp_format import VPPFormat
+
+if sys.version[0] == '2':
+ import Queue as queue
+else:
+ import queue as queue
+
+
+class VppEnumType(type):
+ def __getattr__(cls, name):
+ t = vpp_get_type(name)
+ return t.enum
+
+
+# Python3
+# class VppEnum(metaclass=VppEnumType):
+# pass
+class VppEnum(object):
+ __metaclass__ = VppEnumType
+
+
+def vpp_atexit(vpp_weakref):
+ """Clean up VPP connection on shutdown."""
+ vpp_instance = vpp_weakref()
+ if vpp_instance and vpp_instance.transport.connected:
+ vpp_instance.logger.debug('Cleaning up VPP on exit')
+ vpp_instance.disconnect()
+
+
+def vpp_iterator(d):
+ if sys.version[0] == '2':
+ return d.iteritems()
+ else:
+ return d.items()
+
+
+class VppApiDynamicMethodHolder(object):
+ pass
+
+
+class FuncWrapper(object):
+ def __init__(self, func):
+ self._func = func
+ self.__name__ = func.__name__
+
+ def __call__(self, **kwargs):
+ return self._func(**kwargs)
+
+
+class VPP(object):
+ """VPP interface.
+
+ This class provides the APIs to VPP. The APIs are loaded
+ from provided .api.json files and makes functions accordingly.
+ These functions are documented in the VPP .api files, as they
+ are dynamically created.
+
+ Additionally, VPP can send callback messages; this class
+ provides a means to register a callback function to receive
+ these messages in a background thread.
+ """
+
+ def process_json_file(self, apidef_file):
+ api = json.load(apidef_file)
+ types = {}
+ for t in api['enums']:
+ t[0] = 'vl_api_' + t[0] + '_t'
+ types[t[0]] = {'type': 'enum', 'data': t}
+ for t in api['unions']:
+ t[0] = 'vl_api_' + t[0] + '_t'
+ types[t[0]] = {'type': 'union', 'data': t}
+ for t in api['types']:
+ t[0] = 'vl_api_' + t[0] + '_t'
+ types[t[0]] = {'type': 'type', 'data': t}
+ for t, v in api['aliases'].items():
+ types['vl_api_' + t + '_t'] = {'type': 'alias', 'data': v}
+
+ i = 0
+ while True:
+ unresolved = {}
+ for k, v in types.items():
+ t = v['data']
+ if not vpp_get_type(k):
+ if v['type'] == 'enum':
+ try:
+ VPPEnumType(t[0], t[1:])
+ except ValueError:
+ unresolved[k] = v
+ elif v['type'] == 'union':
+ try:
+ VPPUnionType(t[0], t[1:])
+ except ValueError:
+ unresolved[k] = v
+ elif v['type'] == 'type':
+ try:
+ VPPType(t[0], t[1:])
+ except ValueError:
+ unresolved[k] = v
+ elif v['type'] == 'alias':
+ try:
+ VPPTypeAlias(k, t)
+ except ValueError:
+ unresolved[k] = v
+ if len(unresolved) == 0:
+ break
+ if i > 3:
+ raise ValueError('Unresolved type definitions {}'
+ .format(unresolved))
+ types = unresolved
+ i += 1
+
+ for m in api['messages']:
+ try:
+ self.messages[m[0]] = VPPMessage(m[0], m[1:])
+ except NotImplementedError:
+ self.logger.error('Not implemented error for {}'.format(m[0]))
+
+ def __init__(self, apifiles=None, testmode=False, async_thread=True,
+ logger=None, loglevel=None,
+ read_timeout=5, use_socket=False,
+ server_address='/run/vpp-api.sock'):
+ """Create a VPP API object.
+
+ apifiles is a list of files containing API
+ descriptions that will be loaded - methods will be
+ dynamically created reflecting these APIs. If not
+ provided this will load the API files from VPP's
+ default install location.
+
+ logger, if supplied, is the logging logger object to log to.
+ loglevel, if supplied, is the log level this logger is set
+ to report at (from the loglevels in the logging module).
+ """
+ if logger is None:
+ logger = logging.getLogger(__name__)
+ if loglevel is not None:
+ logger.setLevel(loglevel)
+ self.logger = logger
-def eprint(*args, **kwargs):
- print(*args, file=sys.stderr, **kwargs)
-
-class VPP():
- def __init__(self, apifiles = None, testmode = False):
self.messages = {}
self.id_names = []
self.id_msgdef = []
- self.buffersize = 10000
- self.connected = False
- self.header = struct.Struct('>HI')
- self.results = {}
- self.timeout = 5
- self.apifile = []
+ self.header = VPPType('header', [['u16', 'msgid'],
+ ['u32', 'client_index']])
+ self.apifiles = []
+ self.event_callback = None
+ self.message_queue = queue.Queue()
+ self.read_timeout = read_timeout
+ self.async_thread = async_thread
+
+ if use_socket:
+ from . vpp_transport_socket import VppTransport
+ else:
+ from . vpp_transport_shmem import VppTransport
if not apifiles:
# Pick up API definitions from default directory
- apifiles = glob.glob('/usr/share/vpp/api/*.api.json')
+ try:
+ apifiles = self.find_api_files()
+ except RuntimeError:
+ # In test mode we don't care that we can't find the API files
+ if testmode:
+ apifiles = []
+ else:
+ raise
for file in apifiles:
- self.apifile.append(file)
with open(file) as apidef_file:
- api = json.load(apidef_file)
- for t in api['types']:
- self.add_type(t[0], t[1:])
+ self.process_json_file(apidef_file)
- for m in api['messages']:
- self.add_message(m[0], m[1:])
+ self.apifiles = apifiles
# Basic sanity check
if len(self.messages) == 0 and not testmode:
raise ValueError(1, 'Missing JSON message definitions')
+ self.transport = VppTransport(self, read_timeout=read_timeout,
+ server_address=server_address)
+ # Make sure we allow VPP to clean up the message rings.
+ atexit.register(vpp_atexit, weakref.ref(self))
class ContextId(object):
+ """Thread-safe provider of unique context IDs."""
def __init__(self):
self.context = 0
+ self.lock = threading.Lock()
+
def __call__(self):
- self.context += 1
- return self.context
+ """Get a new unique (or, at least, not recently used) context."""
+ with self.lock:
+ self.context += 1
+ return self.context
get_context = ContextId()
- def status(self):
- print('Connected') if self.connected else print('Not Connected')
- print('Read API definitions from', self.apifile)
-
- def __struct (self, t, n = None, e = -1, vl = None):
- base_types = { 'u8' : 'B',
- 'u16' : 'H',
- 'u32' : 'I',
- 'i32' : 'i',
- 'u64' : 'Q',
- 'f64' : 'd',
- }
- pack = None
- if t in base_types:
- pack = base_types[t]
- if not vl:
- if e > 0 and t == 'u8':
- # Fixed byte array
- return struct.Struct('>' + str(e) + 's')
- if e > 0:
- # Fixed array of base type
- return [e, struct.Struct('>' + base_types[t])]
- elif e == 0:
- # Old style variable array
- return [-1, struct.Struct('>' + base_types[t])]
- else:
- # Variable length array
- return [vl, struct.Struct('>s')] if t == 'u8' else \
- [vl, struct.Struct('>' + base_types[t])]
-
- return struct.Struct('>' + base_types[t])
-
- if t in self.messages:
- ### Return a list in case of array ###
- if e > 0 and not vl:
- return [e, lambda self, encode, buf, offset, args: (
- self.__struct_type(encode, self.messages[t], buf, offset,
- args))]
- if vl:
- return [vl, lambda self, encode, buf, offset, args: (
- self.__struct_type(encode, self.messages[t], buf, offset,
- args))]
- elif e == 0:
- # Old style VLA
- raise NotImplementedError(1, 'No support for compound types ' + t)
- return lambda self, encode, buf, offset, args: (
- self.__struct_type(encode, self.messages[t], buf, offset, args)
- )
-
- raise ValueError(1, 'Invalid message type: ' + t)
-
- def __struct_type(self, encode, msgdef, buf, offset, kwargs):
- if encode:
- return self.__struct_type_encode(msgdef, buf, offset, kwargs)
+ def get_type(self, name):
+ return vpp_get_type(name)
+
+ @classmethod
+ def find_api_dir(cls):
+ """Attempt to find the best directory in which API definition
+ files may reside. If the value VPP_API_DIR exists in the environment
+ then it is first on the search list. If we're inside a recognized
+ location in a VPP source tree (src/scripts and src/vpp-api/python)
+ then entries from there to the likely locations in build-root are
+ added. Finally the location used by system packages is added.
+
+ :returns: A single directory name, or None if no such directory
+ could be found.
+ """
+ dirs = []
+
+ if 'VPP_API_DIR' in os.environ:
+ dirs.append(os.environ['VPP_API_DIR'])
+
+ # perhaps we're in the 'src/scripts' or 'src/vpp-api/python' dir;
+ # in which case, plot a course to likely places in the src tree
+ import __main__ as main
+ if hasattr(main, '__file__'):
+ # get the path of the calling script
+ localdir = os.path.dirname(os.path.realpath(main.__file__))
else:
- return self.__struct_type_decode(msgdef, buf, offset)
-
- def __struct_type_encode(self, msgdef, buf, offset, kwargs):
- off = offset
- size = 0
-
- for k in kwargs:
- if k not in msgdef['args']:
- raise ValueError(1, 'Invalid field-name in message call ' + k)
-
- for k,v in msgdef['args'].iteritems():
- off += size
- if k in kwargs:
- if type(v) is list:
- if callable(v[1]):
- e = kwargs[v[0]] if v[0] in kwargs else v[0]
- size = 0
- for i in range(e):
- size += v[1](self, True, buf, off + size,
- kwargs[k][i])
- else:
- if v[0] in kwargs:
- l = kwargs[v[0]]
- else:
- l = len(kwargs[k])
- if v[1].size == 1:
- buf[off:off + l] = bytearray(kwargs[k])
- size = l
- else:
- size = 0
- for i in kwargs[k]:
- v[1].pack_into(buf, off + size, i)
- size += v[1].size
- else:
- if callable(v):
- size = v(self, True, buf, off, kwargs[k])
- else:
- v.pack_into(buf, off, kwargs[k])
- size = v.size
- else:
- size = v.size if not type(v) is list else 0
-
- return off + size - offset
-
+ # use cwd if there is no calling script
+ localdir = os.getcwd()
+ localdir_s = localdir.split(os.path.sep)
+
+ def dmatch(dir):
+ """Match dir against right-hand components of the script dir"""
+ d = dir.split('/') # param 'dir' assumes a / separator
+ length = len(d)
+ return len(localdir_s) > length and localdir_s[-length:] == d
+
+ def sdir(srcdir, variant):
+ """Build a path from srcdir to the staged API files of
+ 'variant' (typically '' or '_debug')"""
+ # Since 'core' and 'plugin' files are staged
+ # in separate directories, we target the parent dir.
+ return os.path.sep.join((
+ srcdir,
+ 'build-root',
+ 'install-vpp%s-native' % variant,
+ 'vpp',
+ 'share',
+ 'vpp',
+ 'api',
+ ))
+
+ srcdir = None
+ if dmatch('src/scripts'):
+ srcdir = os.path.sep.join(localdir_s[:-2])
+ elif dmatch('src/vpp-api/python'):
+ srcdir = os.path.sep.join(localdir_s[:-3])
+ elif dmatch('test'):
+ # we're apparently running tests
+ srcdir = os.path.sep.join(localdir_s[:-1])
+
+ if srcdir:
+ # we're in the source tree, try both the debug and release
+ # variants.
+ dirs.append(sdir(srcdir, '_debug'))
+ dirs.append(sdir(srcdir, ''))
+
+ # Test for staged copies of the scripts
+ # For these, since we explicitly know if we're running a debug versus
+ # release variant, target only the relevant directory
+ if dmatch('build-root/install-vpp_debug-native/vpp/bin'):
+ srcdir = os.path.sep.join(localdir_s[:-4])
+ dirs.append(sdir(srcdir, '_debug'))
+ if dmatch('build-root/install-vpp-native/vpp/bin'):
+ srcdir = os.path.sep.join(localdir_s[:-4])
+ dirs.append(sdir(srcdir, ''))
+
+ # finally, try the location system packages typically install into
+ dirs.append(os.path.sep.join(('', 'usr', 'share', 'vpp', 'api')))
+
+ # check the directories for existance; first one wins
+ for dir in dirs:
+ if os.path.isdir(dir):
+ return dir
- def __getitem__(self, name):
- if name in self.messages:
- return self.messages[name]
return None
- def encode(self, msgdef, kwargs):
- # Make suitably large buffer
- buf = bytearray(self.buffersize)
- offset = 0
- size = self.__struct_type(True, msgdef, buf, offset, kwargs)
- return buf[:offset + size]
-
- def decode(self, msgdef, buf):
- return self.__struct_type(False, msgdef, buf, 0, None)[1]
-
- def __struct_type_decode(self, msgdef, buf, offset):
- res = []
- off = offset
- size = 0
- for k,v in msgdef['args'].iteritems():
- off += size
- if type(v) is list:
- lst = []
- if callable(v[1]): # compound type
- size = 0
- if v[0] in msgdef['args']: # vla
- e = res[v[2]]
- else: # fixed array
- e = v[0]
- res.append(lst)
- for i in range(e):
- (s,l) = v[1](self, False, buf, off + size, None)
- lst.append(l)
- size += s
- continue
- if v[1].size == 1:
- if type(v[0]) is int:
- size = len(buf) - off
- else:
- size = res[v[2]]
- res.append(buf[off:off + size])
- else:
- e = v[0] if type(v[0]) is int else res[v[2]]
- if e == -1:
- e = (len(buf) - off) / v[1].size
- lst = []
- res.append(lst)
- size = 0
- for i in range(e):
- lst.append(v[1].unpack_from(buf, off + size)[0])
- size += v[1].size
- else:
- if callable(v):
- (s,l) = v(self, False, buf, off, None)
- res.append(l)
- size += s
- else:
- res.append(v.unpack_from(buf, off)[0])
- size = v.size
-
- return off + size - offset, msgdef['return_tuple']._make(res)
-
- def ret_tup(self, name):
- if name in self.messages and 'return_tuple' in self.messages[name]:
- return self.messages[name]['return_tuple']
- return None
-
- def add_message(self, name, msgdef):
- if name in self.messages:
- raise ValueError('Duplicate message name: ' + name)
-
- args = collections.OrderedDict()
- argtypes = collections.OrderedDict()
- fields = []
- msg = {}
- for i, f in enumerate(msgdef):
- if type(f) is dict and 'crc' in f:
- msg['crc'] = f['crc']
- continue
- field_type = f[0]
- field_name = f[1]
- if len(f) == 3 and f[2] == 0 and i != len(msgdef) - 2:
- raise ValueError('Variable Length Array must be last: ' + name)
- args[field_name] = self.__struct(*f)
- argtypes[field_name] = field_type
- if len(f) == 4: # Find offset to # elements field
- args[field_name].append(args.keys().index(f[3]) - i)
- fields.append(field_name)
- msg['return_tuple'] = collections.namedtuple(name, fields,
- rename = True)
- self.messages[name] = msg
- self.messages[name]['args'] = args
- self.messages[name]['argtypes'] = argtypes
- return self.messages[name]
-
- def add_type(self, name, typedef):
- return self.add_message('vl_api_' + name + '_t', typedef)
-
- def make_function(self, name, i, msgdef, multipart, async):
- if (async):
- f = lambda **kwargs: (self._call_vpp_async(i, msgdef, multipart, **kwargs))
+ @classmethod
+ def find_api_files(cls, api_dir=None, patterns='*'):
+ """Find API definition files from the given directory tree with the
+ given pattern. If no directory is given then find_api_dir() is used
+ to locate one. If no pattern is given then all definition files found
+ in the directory tree are used.
+
+ :param api_dir: A directory tree in which to locate API definition
+ files; subdirectories are descended into.
+ If this is None then find_api_dir() is called to discover it.
+ :param patterns: A list of patterns to use in each visited directory
+ when looking for files.
+ This can be a list/tuple object or a comma-separated string of
+ patterns. Each value in the list will have leading/trialing
+ whitespace stripped.
+ The pattern specifies the first part of the filename, '.api.json'
+ is appended.
+ The results are de-duplicated, thus overlapping patterns are fine.
+ If this is None it defaults to '*' meaning "all API files".
+ :returns: A list of file paths for the API files found.
+ """
+ if api_dir is None:
+ api_dir = cls.find_api_dir()
+ if api_dir is None:
+ raise RuntimeError("api_dir cannot be located")
+
+ if isinstance(patterns, list) or isinstance(patterns, tuple):
+ patterns = [p.strip() + '.api.json' for p in patterns]
+ else:
+ patterns = [p.strip() + '.api.json' for p in patterns.split(",")]
+
+ api_files = []
+ for root, dirnames, files in os.walk(api_dir):
+ # iterate all given patterns and de-dup the result
+ files = set(sum([fnmatch.filter(files, p) for p in patterns], []))
+ for filename in files:
+ api_files.append(os.path.join(root, filename))
+
+ return api_files
+
+ @property
+ def api(self):
+ if not hasattr(self, "_api"):
+ raise Exception("Not connected, api definitions not available")
+ return self._api
+
+ def make_function(self, msg, i, multipart, do_async):
+ if (do_async):
+ def f(**kwargs):
+ return self._call_vpp_async(i, msg, **kwargs)
else:
- f = lambda **kwargs: (self._call_vpp(i, msgdef, multipart, **kwargs))
- args = self.messages[name]['args']
- argtypes = self.messages[name]['argtypes']
- f.__name__ = str(name)
- f.__doc__ = ", ".join(["%s %s" % (argtypes[k], k) for k in args.keys()])
+ def f(**kwargs):
+ return self._call_vpp(i, msg, multipart, **kwargs)
+
+ f.__name__ = str(msg.name)
+ f.__doc__ = ", ".join(["%s %s" %
+ (msg.fieldtypes[j], k)
+ for j, k in enumerate(msg.fields)])
return f
- def _register_functions(self, async=False):
+ def _register_functions(self, do_async=False):
self.id_names = [None] * (self.vpp_dictionary_maxid + 1)
self.id_msgdef = [None] * (self.vpp_dictionary_maxid + 1)
- for name, msgdef in self.messages.iteritems():
- if name in self.vpp_dictionary:
- if self.messages[name]['crc'] != self.vpp_dictionary[name]['crc']:
- raise ValueError(3, 'Failed CRC checksum ' + name +
- ' ' + self.messages[name]['crc'] +
- ' ' + self.vpp_dictionary[name]['crc'])
- i = self.vpp_dictionary[name]['id']
- self.id_msgdef[i] = msgdef
+ self._api = VppApiDynamicMethodHolder()
+ for name, msg in vpp_iterator(self.messages):
+ n = name + '_' + msg.crc[2:]
+ i = self.transport.get_msg_index(n.encode())
+ if i > 0:
+ self.id_msgdef[i] = msg
self.id_names[i] = name
+ # TODO: Fix multipart (use services)
multipart = True if name.find('_dump') > 0 else False
- setattr(self, name, self.make_function(name, i, msgdef, multipart, async))
-
- def _write (self, buf):
- if not self.connected:
- raise IOError(1, 'Not connected')
- return vpp_api.write(str(buf))
-
- def _load_dictionary(self):
- self.vpp_dictionary = {}
- self.vpp_dictionary_maxid = 0
- d = vpp_api.msg_table()
-
- if not d:
- raise IOError(3, 'Cannot get VPP API dictionary')
- for i,n in d:
- name, crc = n.rsplit('_', 1)
- crc = '0x' + crc
- self.vpp_dictionary[name] = { 'id' : i, 'crc' : crc }
- self.vpp_dictionary_maxid = max(self.vpp_dictionary_maxid, i)
-
- def connect(self, name, chroot_prefix = None, async = False):
- msg_handler = self.msg_handler if not async else self.msg_handler_async
- if not chroot_prefix:
- rv = vpp_api.connect(name, msg_handler)
- else:
- rv = vpp_api.connect(name, msg_handler, chroot_prefix)
+ f = self.make_function(msg, i, multipart, do_async)
+ setattr(self._api, name, FuncWrapper(f))
+ else:
+ self.logger.debug(
+ 'No such message type or failed CRC checksum: %s', n)
+ def connect_internal(self, name, msg_handler, chroot_prefix, rx_qlen,
+ do_async):
+ pfx = chroot_prefix.encode() if chroot_prefix else None
+
+ rv = self.transport.connect(name.encode(), pfx, msg_handler, rx_qlen)
if rv != 0:
raise IOError(2, 'Connect failed')
- self.connected = True
-
- self._load_dictionary()
- self._register_functions(async=async)
+ self.vpp_dictionary_maxid = self.transport.msg_table_max_index()
+ self._register_functions(do_async=do_async)
# Initialise control ping
- self.control_ping_index = self.vpp_dictionary['control_ping']['id']
+ crc = self.messages['control_ping'].crc
+ self.control_ping_index = self.transport.get_msg_index(
+ ('control_ping' + '_' + crc[2:]).encode())
self.control_ping_msgdef = self.messages['control_ping']
-
- def disconnect(self):
- rv = vpp_api.disconnect()
+ if self.async_thread:
+ self.event_thread = threading.Thread(
+ target=self.thread_msg_handler)
+ self.event_thread.daemon = True
+ self.event_thread.start()
return rv
- def results_wait(self, context):
- return (self.results[context]['e'].wait(self.timeout))
+ def connect(self, name, chroot_prefix=None, do_async=False, rx_qlen=32):
+ """Attach to VPP.
- def results_prepare(self, context):
- self.results[context] = {}
- self.results[context]['e'] = threading.Event()
- self.results[context]['e'].clear()
- self.results[context]['r'] = []
+ name - the name of the client.
+ chroot_prefix - if VPP is chroot'ed, the prefix of the jail
+ do_async - if true, messages are sent without waiting for a reply
+ rx_qlen - the length of the VPP message receive queue between
+ client and server.
+ """
+ msg_handler = self.transport.get_callback(do_async)
+ return self.connect_internal(name, msg_handler, chroot_prefix, rx_qlen,
+ do_async)
- def results_clean(self, context):
- del self.results[context]
-
- def msg_handler(self, msg):
- if not msg:
- eprint('vpp_api.read failed')
- return
-
- i, ci = self.header.unpack_from(msg, 0)
- if self.id_names[i] == 'rx_thread_exit':
- return;
-
- #
- # Decode message and returns a tuple.
- #
- msgdef = self.id_msgdef[i]
- if not msgdef:
- raise IOError(2, 'Reply message undefined')
+ def connect_sync(self, name, chroot_prefix=None, rx_qlen=32):
+ """Attach to VPP in synchronous mode. Application must poll for events.
- r = self.decode(msgdef, msg)
- if 'context' in r._asdict():
- if r.context > 0:
- context = r.context
+ name - the name of the client.
+ chroot_prefix - if VPP is chroot'ed, the prefix of the jail
+ rx_qlen - the length of the VPP message receive queue between
+ client and server.
+ """
- msgname = type(r).__name__
+ return self.connect_internal(name, None, chroot_prefix, rx_qlen,
+ do_async=False)
- #
- # XXX: Call provided callback for event
- # Are we guaranteed to not get an event during processing of other messages?
- # How to differentiate what's a callback message and what not? Context = 0?
- #
- #if not is_waiting_for_reply():
- if r.context == 0 and self.event_callback:
- self.event_callback(msgname, r)
- return
+ def disconnect(self):
+ """Detach from VPP."""
+ rv = self.transport.disconnect()
+ self.message_queue.put("terminate event thread")
+ return rv
- #
- # Collect results until control ping
- #
- if msgname == 'control_ping_reply':
- self.results[context]['e'].set()
- return
+ def msg_handler_sync(self, msg):
+ """Process an incoming message from VPP in sync mode.
- if not context in self.results:
- eprint('Not expecting results for this context', context, r)
+ The message may be a reply or it may be an async notification.
+ """
+ r = self.decode_incoming_msg(msg)
+ if r is None:
return
- if 'm' in self.results[context]:
- self.results[context]['r'].append(r)
- return
+ # If we have a context, then use the context to find any
+ # request waiting for a reply
+ context = 0
+ if hasattr(r, 'context') and r.context > 0:
+ context = r.context
- self.results[context]['r'] = r
- self.results[context]['e'].set()
+ if context == 0:
+ # No context -> async notification that we feed to the callback
+ self.message_queue.put_nowait(r)
+ else:
+ raise IOError(2, 'RPC reply message received in event handler')
- def msg_handler_async(self, msg):
+ def decode_incoming_msg(self, msg):
if not msg:
- eprint('vpp_api.read failed')
+ self.logger.warning('vpp_api.read failed')
return
-
- i, ci = self.header.unpack_from(msg, 0)
+ (i, ci), size = self.header.unpack(msg, 0)
if self.id_names[i] == 'rx_thread_exit':
- return;
+ return
#
# Decode message and returns a tuple.
#
- msgdef = self.id_msgdef[i]
- if not msgdef:
+ msgobj = self.id_msgdef[i]
+ if not msgobj:
raise IOError(2, 'Reply message undefined')
- r = self.decode(msgdef, msg)
+ r, size = msgobj.unpack(msg)
+ return r
+
+ def msg_handler_async(self, msg):
+ """Process a message from VPP in async mode.
+
+ In async mode, all messages are returned to the callback.
+ """
+ r = self.decode_incoming_msg(msg)
+ if r is None:
+ return
+
msgname = type(r).__name__
- self.event_callback(msgname, r)
+ if self.event_callback:
+ self.event_callback(msgname, r)
def _control_ping(self, context):
- self._write(self.encode(self.control_ping_msgdef,
- { '_vl_msg_id' : self.control_ping_index,
- 'context' : context}))
-
- def _call_vpp(self, i, msgdef, multipart, **kwargs):
- if not 'context' in kwargs:
+ """Send a ping command."""
+ self._call_vpp_async(self.control_ping_index,
+ self.control_ping_msgdef,
+ context=context)
+
+ def validate_args(self, msg, kwargs):
+ d = set(kwargs.keys()) - set(msg.field_by_name.keys())
+ if d:
+ raise ValueError('Invalid argument {} to {}'
+ .format(list(d), msg.name))
+
+ def _call_vpp(self, i, msg, multipart, **kwargs):
+ """Given a message, send the message and await a reply.
+
+ msgdef - the message packing definition
+ i - the message type index
+ multipart - True if the message returns multiple
+ messages in return.
+ context - context number - chosen at random if not
+ supplied.
+ The remainder of the kwargs are the arguments to the API call.
+
+ The return value is the message or message array containing
+ the response. It will raise an IOError exception if there was
+ no response within the timeout window.
+ """
+
+ if 'context' not in kwargs:
context = self.get_context()
kwargs['context'] = context
else:
context = kwargs['context']
kwargs['_vl_msg_id'] = i
- b = self.encode(msgdef, kwargs)
- self.results_prepare(context)
- self._write(b)
+ try:
+ if self.transport.socket_index:
+ kwargs['client_index'] = self.transport.socket_index
+ except AttributeError:
+ pass
+ self.validate_args(msg, kwargs)
+ b = msg.pack(kwargs)
+ self.transport.suspend()
+
+ self.transport.write(b)
if multipart:
- self.results[context]['m'] = True
+ # Send a ping after the request - we use its response
+ # to detect that we have seen all results.
self._control_ping(context)
- self.results_wait(context)
- r = self.results[context]['r']
- self.results_clean(context)
- return r
- def _call_vpp_async(self, i, msgdef, multipart, **kwargs):
- if not 'context' in kwargs:
+ # Block until we get a reply.
+ rl = []
+ while (True):
+ msg = self.transport.read()
+ if not msg:
+ raise IOError(2, 'VPP API client: read failed')
+ r = self.decode_incoming_msg(msg)
+ msgname = type(r).__name__
+ if context not in r or r.context == 0 or context != r.context:
+ # Message being queued
+ self.message_queue.put_nowait(r)
+ continue
+
+ if not multipart:
+ rl = r
+ break
+ if msgname == 'control_ping_reply':
+ break
+
+ rl.append(r)
+
+ self.transport.resume()
+
+ return rl
+
+ def _call_vpp_async(self, i, msg, **kwargs):
+ """Given a message, send the message and await a reply.
+
+ msgdef - the message packing definition
+ i - the message type index
+ context - context number - chosen at random if not
+ supplied.
+ The remainder of the kwargs are the arguments to the API call.
+ """
+ if 'context' not in kwargs:
context = self.get_context()
kwargs['context'] = context
else:
context = kwargs['context']
+ try:
+ if self.transport.socket_index:
+ kwargs['client_index'] = self.transport.socket_index
+ except AttributeError:
+ kwargs['client_index'] = 0
kwargs['_vl_msg_id'] = i
- b = self.encode(msgdef, kwargs)
+ b = msg.pack(kwargs)
- self._write(b)
+ self.transport.write(b)
def register_event_callback(self, callback):
+ """Register a callback for async messages.
+
+ This will be called for async notifications in sync mode,
+ and all messages in async mode. In sync mode, replies to
+ requests will not come here.
+
+ callback is a fn(msg_type_name, msg_type) that will be
+ called when a message comes in. While this function is
+ executing, note that (a) you are in a background thread and
+ may wish to use threading.Lock to protect your datastructures,
+ and (b) message processing from VPP will stop (so if you take
+ a long while about it you may provoke reply timeouts or cause
+ VPP to fill the RX buffer). Passing None will disable the
+ callback.
+ """
self.event_callback = callback
+ def thread_msg_handler(self):
+ """Python thread calling the user registered message handler.
+
+ This is to emulate the old style event callback scheme. Modern
+ clients should provide their own thread to poll the event
+ queue.
+ """
+ while True:
+ r = self.message_queue.get()
+ if r == "terminate event thread":
+ break
+ msgname = type(r).__name__
+ if self.event_callback:
+ self.event_callback(msgname, r)
+
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4
Code Review / vpp.git / blobdiff