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authorOle Troan <ot@cisco.com>2018-06-12 21:06:44 +0200
committerFlorin Coras <florin.coras@gmail.com>2018-06-22 03:00:45 +0000
commita7564e8004fd6d9a63eb0605f752f27a71403645 (patch)
tree15a97b1b7852dfbdee28c56e0d58218689126c1b /src/vpp-api/python/vpp_papi
parentd600ffe13a0f8f5d11fdea6ab7b24a364c968347 (diff)
Python API: Add enum and union support.
As well as a rewrite of the encoders/decoders to make it more readable and extensible. (Re-commit after fix to verify build.) Change-Id: Ic244d3cebe070bb2570491f8a24f4a1e203f889a Signed-off-by: Ole Troan <ot@cisco.com>
Diffstat (limited to 'src/vpp-api/python/vpp_papi')
-rw-r--r--src/vpp-api/python/vpp_papi/__init__.py1
-rw-r--r--src/vpp-api/python/vpp_papi/vpp_papi.py679
-rw-r--r--src/vpp-api/python/vpp_papi/vpp_serializer.py343
3 files changed, 1023 insertions, 0 deletions
diff --git a/src/vpp-api/python/vpp_papi/__init__.py b/src/vpp-api/python/vpp_papi/__init__.py
new file mode 100644
index 00000000000..f9afcf17f29
--- /dev/null
+++ b/src/vpp-api/python/vpp_papi/__init__.py
@@ -0,0 +1 @@
+from .vpp_papi import *
diff --git a/src/vpp-api/python/vpp_papi/vpp_papi.py b/src/vpp-api/python/vpp_papi/vpp_papi.py
new file mode 100644
index 00000000000..edc0c6ab364
--- /dev/null
+++ b/src/vpp-api/python/vpp_papi/vpp_papi.py
@@ -0,0 +1,679 @@
+#!/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
+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 cffi import FFI
+import cffi
+from . vpp_serializer import VPPType, VPPEnumType, VPPUnionType, BaseTypes
+from . vpp_serializer import VPPMessage
+
+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 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
diff --git a/src/vpp-api/python/vpp_papi/vpp_serializer.py b/src/vpp-api/python/vpp_papi/vpp_serializer.py
new file mode 100644
index 00000000000..7f5c5ace2dc
--- /dev/null
+++ b/src/vpp-api/python/vpp_papi/vpp_serializer.py
@@ -0,0 +1,343 @@
+#
+# Copyright (c) 2018 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.
+#
+
+import struct
+import collections
+from enum import IntEnum
+import logging
+
+#
+# Set log-level in application by doing e.g.:
+# logger = logging.getLogger('vpp_serializer')
+# logger.setLevel(logging.DEBUG)
+#
+logger = logging.getLogger(__name__)
+
+
+class BaseTypes():
+ def __init__(self, type, elements=0):
+ base_types = {'u8': '>B',
+ 'u16': '>H',
+ 'u32': '>I',
+ 'i32': '>i',
+ 'u64': '>Q',
+ 'f64': '>d',
+ 'header': '>HI'}
+
+ if elements > 0 and type == 'u8':
+ self.packer = struct.Struct('>%ss' % elements)
+ else:
+ self.packer = struct.Struct(base_types[type])
+ self.size = self.packer.size
+ logger.debug('Adding {} with format: {}'
+ .format(type, base_types[type]))
+
+ def pack(self, data, kwargs=None):
+ logger.debug("Data: {} Format: {}".format(data, self.packer.format))
+ return self.packer.pack(data)
+
+ def unpack(self, data, offset, result=None):
+ logger.debug("@ {} Format: {}".format(offset, self.packer.format))
+ return self.packer.unpack_from(data, offset)[0]
+
+
+types = {}
+types['u8'] = BaseTypes('u8')
+types['u16'] = BaseTypes('u16')
+types['u32'] = BaseTypes('u32')
+types['i32'] = BaseTypes('i32')
+types['u64'] = BaseTypes('u64')
+types['f64'] = BaseTypes('f64')
+
+
+class FixedList_u8():
+ def __init__(self, name, field_type, num):
+ self.name = name
+ self.num = num
+ self.packer = BaseTypes(field_type, num)
+ self.size = self.packer.size
+
+ def pack(self, list, kwargs):
+ """Packs a fixed length bytestring. Left-pads with zeros
+ if input data is too short."""
+ logger.debug("Data: {}".format(list))
+
+ if len(list) > self.num:
+ raise ValueError('Fixed list length error for "{}", got: {}'
+ ' expected: {}'
+ .format(self.name, len(list), self.num))
+ return self.packer.pack(list)
+
+ def unpack(self, data, offset=0, result=None):
+ if len(data[offset:]) < self.num:
+ raise ValueError('Invalid array length for "{}" got {}'
+ ' expected {}'
+ .format(self.name, len(data), self.num))
+ return self.packer.unpack(data, offset)
+
+
+class FixedList():
+ def __init__(self, name, field_type, num):
+ self.num = num
+ self.packer = types[field_type]
+ self.size = self.packer.size * num
+
+ def pack(self, list, kwargs):
+ logger.debug("Data: {}".format(list))
+
+ if len(list) != self.num:
+ raise ValueError('Fixed list length error, got: {} expected: {}'
+ .format(len(list), self.num))
+ b = bytes()
+ for e in list:
+ b += self.packer.pack(e)
+ return b
+
+ def unpack(self, data, offset=0, result=None):
+ # Return a list of arguments
+ result = []
+ for e in range(self.num):
+ x = self.packer.unpack(data, offset)
+ result.append(x)
+ offset += self.packer.size
+ return result
+
+
+class VLAList():
+ def __init__(self, name, field_type, len_field_name, index):
+ self.index = index
+ self.packer = types[field_type]
+ self.size = self.packer.size
+ self.length_field = len_field_name
+
+ def pack(self, list, kwargs=None):
+ logger.debug("Data: {}".format(list))
+ if len(list) != kwargs[self.length_field]:
+ raise ValueError('Variable length error, got: {} expected: {}'
+ .format(len(list), kwargs[self.length_field]))
+ b = bytes()
+
+ # u8 array
+ if self.packer.size == 1:
+ return bytearray(list)
+
+ for e in list:
+ b += self.packer.pack(e)
+ return b
+
+ def unpack(self, data, offset=0, result=None):
+ logger.debug("Data: {} @ {} Result: {}"
+ .format(list, offset, result[self.index]))
+ # Return a list of arguments
+
+ # u8 array
+ if self.packer.size == 1:
+ if result[self.index] == 0:
+ return b''
+ p = BaseTypes('u8', result[self.index])
+ r = p.unpack(data, offset)
+ return r
+
+ r = []
+ for e in range(result[self.index]):
+ x = self.packer.unpack(data, offset)
+ r.append(x)
+ offset += self.packer.size
+ return r
+
+
+class VLAList_legacy():
+ def __init__(self, name, field_type):
+ self.packer = types[field_type]
+ self.size = self.packer.size
+
+ def pack(self, list, kwargs=None):
+ logger.debug("Data: {}".format(list))
+
+ if self.packer.size == 1:
+ return bytes(list)
+
+ b = bytes()
+ for e in list:
+ b += self.packer.pack(e)
+ return b
+
+ def unpack(self, data, offset=0, result=None):
+ # Return a list of arguments
+ if (len(data) - offset) % self.packer.size:
+ raise ValueError('Legacy Variable Length Array length mismatch.')
+ elements = int((len(data) - offset) / self.packer.size)
+ r = []
+ logger.debug("Legacy VLA: {} elements of size {}"
+ .format(elements, self.packer.size))
+ for e in range(elements):
+ x = self.packer.unpack(data, offset)
+ r.append(x)
+ offset += self.packer.size
+ return r
+
+
+class VPPEnumType():
+ def __init__(self, name, msgdef):
+ self.size = types['u32'].size
+ e_hash = {}
+ for f in msgdef:
+ if type(f) is dict and 'enumtype' in f:
+ if f['enumtype'] != 'u32':
+ raise NotImplementedError
+ continue
+ ename, evalue = f
+ e_hash[ename] = evalue
+ self.enum = IntEnum(name, e_hash)
+ types[name] = self
+ logger.debug('Adding enum {}'.format(name))
+
+ def __getattr__(self, name):
+ return self.enum[name]
+
+ def pack(self, data, kwargs=None):
+ logger.debug("Data: {}".format(data))
+ return types['u32'].pack(data, kwargs)
+
+ def unpack(self, data, offset=0, result=None):
+ x = types['u32'].unpack(data, offset)
+ return self.enum(x)
+
+
+class VPPUnionType():
+ def __init__(self, name, msgdef):
+ self.name = name
+ self.size = 0
+ self.maxindex = 0
+ fields = []
+ self.packers = collections.OrderedDict()
+ for i, f in enumerate(msgdef):
+ if type(f) is dict and 'crc' in f:
+ self.crc = f['crc']
+ continue
+ f_type, f_name = f
+ if f_type not in types:
+ logger.debug('Unknown union type {}'.format(f_type))
+ raise ValueError('Unknown message type {}'.format(f_type))
+ fields.append(f_name)
+ size = types[f_type].size
+ self.packers[f_name] = types[f_type]
+ if size > self.size:
+ self.size = size
+ self.maxindex = i
+
+ types[name] = self
+ self.tuple = collections.namedtuple(name, fields, rename=True)
+ logger.debug('Adding union {}'.format(name))
+
+ def pack(self, data, kwargs=None):
+ logger.debug("Data: {}".format(data))
+ for k, v in data.items():
+ logger.debug("Key: {} Value: {}".format(k, v))
+ b = self.packers[k].pack(v, kwargs)
+ offset = self.size - self.packers[k].size
+ break
+ r = bytearray(self.size)
+ r[offset:] = b
+ return r
+
+ def unpack(self, data, offset=0, result=None):
+ r = []
+ for k, p in self.packers.items():
+ union_offset = self.size - p.size
+ r.append(p.unpack(data, offset + union_offset))
+ return self.tuple._make(r)
+
+
+class VPPType():
+ # Set everything up to be able to pack / unpack
+ def __init__(self, name, msgdef):
+ self.name = name
+ self.msgdef = msgdef
+ self.packers = []
+ self.fields = []
+ self.fieldtypes = []
+ self.field_by_name = {}
+ size = 0
+ for i, f in enumerate(msgdef):
+ if type(f) is dict and 'crc' in f:
+ self.crc = f['crc']
+ continue
+ f_type, f_name = f[:2]
+ self.fields.append(f_name)
+ self.field_by_name[f_name] = None
+ self.fieldtypes.append(f_type)
+ if f_type not in types:
+ logger.debug('Unknown type {}'.format(f_type))
+ raise ValueError('Unknown message type {}'.format(f_type))
+ if len(f) == 3: # list
+ list_elements = f[2]
+ if list_elements == 0:
+ p = VLAList_legacy(f_name, f_type)
+ self.packers.append(p)
+ elif f_type == 'u8':
+ p = FixedList_u8(f_name, f_type, list_elements)
+ self.packers.append(p)
+ size += p.size
+ else:
+ p = FixedList(f_name, f_type, list_elements)
+ self.packers.append(p)
+ size += p.size
+ elif len(f) == 4: # Variable length list
+ # Find index of length field
+ length_index = self.fields.index(f[3])
+ p = VLAList(f_name, f_type, f[3], length_index)
+ self.packers.append(p)
+ else:
+ self.packers.append(types[f_type])
+ size += types[f_type].size
+
+ self.size = size
+ self.tuple = collections.namedtuple(name, self.fields, rename=True)
+ types[name] = self
+ logger.debug('Adding type {}'.format(name))
+
+ def pack(self, data, kwargs=None):
+ if not kwargs:
+ kwargs = data
+ logger.debug("Data: {}".format(data))
+ b = bytes()
+ for i, a in enumerate(self.fields):
+ if a not in data:
+ logger.debug("Argument {} not given, defaulting to 0"
+ .format(a))
+ b += b'\x00' * self.packers[i].size
+ continue
+
+ if isinstance(self.packers[i], VPPType):
+ b += self.packers[i].pack(data[a], kwargs[a])
+ else:
+ b += self.packers[i].pack(data[a], kwargs)
+ return b
+
+ def unpack(self, data, offset=0, result=None):
+ # Return a list of arguments
+ result = []
+ for p in self.packers:
+ x = p.unpack(data, offset, result)
+ if type(x) is tuple and len(x) == 1:
+ x = x[0]
+ result.append(x)
+ offset += p.size
+ return self.tuple._make(result)
+
+
+class VPPMessage(VPPType):
+ pass