diff options
Diffstat (limited to 'src/vpp-api/python/vpp_papi/vpp_papi.py')
| -rw-r--r-- | src/vpp-api/python/vpp_papi/vpp_papi.py | 678 |
1 files changed, 0 insertions, 678 deletions
diff --git a/src/vpp-api/python/vpp_papi/vpp_papi.py b/src/vpp-api/python/vpp_papi/vpp_papi.py deleted file mode 100644 index 5ff8064d425..00000000000 --- a/src/vpp-api/python/vpp_papi/vpp_papi.py +++ /dev/null @@ -1,678 +0,0 @@ -#!/usr/bin/env python -# -# Copyright (c) 2016 Cisco and/or its affiliates. -# Licensed under the Apache License, Version 2.0 (the "License"); -# you may not use this file except in compliance with the License. -# You may obtain a copy of the License at: -# -# http://www.apache.org/licenses/LICENSE-2.0 -# -# Unless required by applicable law or agreed to in writing, software -# distributed under the License is distributed on an "AS IS" BASIS, -# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -# See the License for the specific language governing permissions and -# limitations under the License. -# - -from __future__ import print_function -import sys -import os -import logging -import collections -import struct -import json -import threading -import fnmatch -import weakref -import atexit -from cffi import FFI -import cffi -from vpp_serializer import VPPType, VPPEnumType, VPPUnionType, BaseTypes - -if sys.version[0] == '2': - import Queue as queue -else: - import queue as queue - -ffi = FFI() -ffi.cdef(""" -typedef void (*vac_callback_t)(unsigned char * data, int len); -typedef void (*vac_error_callback_t)(void *, unsigned char *, int); -int vac_connect(char * name, char * chroot_prefix, vac_callback_t cb, - int rx_qlen); -int vac_disconnect(void); -int vac_read(char **data, int *l, unsigned short timeout); -int vac_write(char *data, int len); -void vac_free(void * msg); - -int vac_get_msg_index(unsigned char * name); -int vac_msg_table_size(void); -int vac_msg_table_max_index(void); - -void vac_rx_suspend (void); -void vac_rx_resume (void); -void vac_set_error_handler(vac_error_callback_t); - """) - -# Barfs on failure, no need to check success. -vpp_api = ffi.dlopen('libvppapiclient.so') - - -def vpp_atexit(vpp_weakref): - """Clean up VPP connection on shutdown.""" - vpp_instance = vpp_weakref() - if vpp_instance.connected: - vpp_instance.logger.debug('Cleaning up VPP on exit') - vpp_instance.disconnect() - - -vpp_object = None - - -def vpp_iterator(d): - if sys.version[0] == '2': - return d.iteritems() - else: - return d.items() - - -@ffi.callback("void(unsigned char *, int)") -def vac_callback_sync(data, len): - vpp_object.msg_handler_sync(ffi.buffer(data, len)) - - -@ffi.callback("void(unsigned char *, int)") -def vac_callback_async(data, len): - vpp_object.msg_handler_async(ffi.buffer(data, len)) - - -@ffi.callback("void(void *, unsigned char *, int)") -def vac_error_handler(arg, msg, msg_len): - vpp_object.logger.warning("VPP API client:: %s", ffi.string(msg, msg_len)) - - -class Empty(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 VPPMessage(VPPType): - pass - -class VPP(): - """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} - - i = 0 - while True: - unresolved = {} - for k, v in types.items(): - t = v['data'] - 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 - 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=logging.getLogger('vpp_papi'), loglevel='debug', - read_timeout=0): - """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). - """ - global vpp_object - vpp_object = self - - if logger is None: - logger = logging.getLogger(__name__) - if loglevel is not None: - logger.setLevel(loglevel) - self.logger = logger - - self.messages = {} - self.id_names = [] - self.id_msgdef = [] - self.connected = False - 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.vpp_api = vpp_api - self.async_thread = async_thread - - if not apifiles: - # Pick up API definitions from default directory - 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: - with open(file) as apidef_file: - self.process_json_file(apidef_file) - - self.apifiles = apifiles - - # Basic sanity check - if len(self.messages) == 0 and not testmode: - raise ValueError(1, 'Missing JSON message definitions') - - # Make sure we allow VPP to clean up the message rings. - atexit.register(vpp_atexit, weakref.ref(self)) - - # Register error handler - if not testmode: - vpp_api.vac_set_error_handler(vac_error_handler) - - # Support legacy CFFI - # from_buffer supported from 1.8.0 - (major, minor, patch) = [int(s) for s in - cffi.__version__.split('.', 3)] - if major >= 1 and minor >= 8: - self._write = self._write_new_cffi - else: - self._write = self._write_legacy_cffi - - class ContextId(object): - """Thread-safe provider of unique context IDs.""" - def __init__(self): - self.context = 0 - self.lock = threading.Lock() - - def __call__(self): - """Get a new unique (or, at least, not recently used) context.""" - with self.lock: - self.context += 1 - return self.context - get_context = ContextId() - - @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: - # 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 - - return None - - @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 - - def status(self): - """Debug function: report current VPP API status to stdout.""" - print('Connected') if self.connected else print('Not Connected') - print('Read API definitions from', ', '.join(self.apifiles)) - - @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, async): - if (async): - def f(**kwargs): - return self._call_vpp_async(i, msg, **kwargs) - else: - 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): - self.id_names = [None] * (self.vpp_dictionary_maxid + 1) - self.id_msgdef = [None] * (self.vpp_dictionary_maxid + 1) - self._api = Empty() - for name, msg in vpp_iterator(self.messages): - n = name + '_' + msg.crc[2:] - i = vpp_api.vac_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 - f = self.make_function(msg, i, multipart, async) - setattr(self._api, name, FuncWrapper(f)) - else: - self.logger.debug( - 'No such message type or failed CRC checksum: %s', n) - - def _write_new_cffi(self, buf): - """Send a binary-packed message to VPP.""" - if not self.connected: - raise IOError(1, 'Not connected') - return vpp_api.vac_write(ffi.from_buffer(buf), len(buf)) - - def _write_legacy_cffi(self, buf): - """Send a binary-packed message to VPP.""" - if not self.connected: - raise IOError(1, 'Not connected') - return vpp_api.vac_write(bytes(buf), len(buf)) - - def _read(self): - if not self.connected: - raise IOError(1, 'Not connected') - mem = ffi.new("char **") - size = ffi.new("int *") - rv = vpp_api.vac_read(mem, size, self.read_timeout) - if rv: - raise IOError(rv, 'vac_read failed') - msg = bytes(ffi.buffer(mem[0], size[0])) - vpp_api.vac_free(mem[0]) - return msg - - def connect_internal(self, name, msg_handler, chroot_prefix, rx_qlen, - async): - pfx = chroot_prefix.encode() if chroot_prefix else ffi.NULL - rv = vpp_api.vac_connect(name.encode(), pfx, msg_handler, rx_qlen) - if rv != 0: - raise IOError(2, 'Connect failed') - self.connected = True - self.vpp_dictionary_maxid = vpp_api.vac_msg_table_max_index() - self._register_functions(async=async) - - # Initialise control ping - crc = self.messages['control_ping'].crc - self.control_ping_index = vpp_api.vac_get_msg_index( - ('control_ping' + '_' + crc[2:]).encode()) - self.control_ping_msgdef = self.messages['control_ping'] - 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 connect(self, name, chroot_prefix=None, async=False, rx_qlen=32): - """Attach to VPP. - - name - the name of the client. - chroot_prefix - if VPP is chroot'ed, the prefix of the jail - 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 = vac_callback_sync if not async else vac_callback_async - return self.connect_internal(name, msg_handler, chroot_prefix, rx_qlen, - async) - - def connect_sync(self, name, chroot_prefix=None, rx_qlen=32): - """Attach to VPP in synchronous mode. Application must poll for events. - - 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. - """ - - return self.connect_internal(name, ffi.NULL, chroot_prefix, rx_qlen, - async=False) - - def disconnect(self): - """Detach from VPP.""" - rv = vpp_api.vac_disconnect() - self.connected = False - self.message_queue.put("terminate event thread") - return rv - - def msg_handler_sync(self, msg): - """Process an incoming message from VPP in sync mode. - - 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 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 - - 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 decode_incoming_msg(self, msg): - if not msg: - self.logger.warning('vpp_api.read failed') - return - - i, ci = self.header.unpack(msg, 0) - if self.id_names[i] == 'rx_thread_exit': - return - - # - # Decode message and returns a tuple. - # - msgobj = self.id_msgdef[i] - if not msgobj: - raise IOError(2, 'Reply message undefined') - - r = 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__ - - if self.event_callback: - self.event_callback(msgname, r) - - def _control_ping(self, context): - """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 - - self.validate_args(msg, kwargs) - b = msg.pack(kwargs) - vpp_api.vac_rx_suspend() - self._write(b) - - if multipart: - # Send a ping after the request - we use its response - # to detect that we have seen all results. - self._control_ping(context) - - # Block until we get a reply. - rl = [] - while (True): - msg = self._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: - self.message_queue.put_nowait(r) - continue - - if not multipart: - rl = r - break - if msgname == 'control_ping_reply': - break - - rl.append(r) - - vpp_api.vac_rx_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'] - kwargs['client_index'] = 0 - kwargs['_vl_msg_id'] = i - b = msg.pack(kwargs) - - self._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 registerd 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 |