X-Git-Url: https://gerrit.fd.io/r/gitweb?p=csit.git;a=blobdiff_plain;f=resources%2Flibraries%2Fpython%2FPapiExecutor.py;h=ecee70c9c5e14ee284c9e65652145bb31a73273b;hp=ad0de27b82697aaa4afe0398d6f9de0dcf48babf;hb=b6606e7625e308a66bdfb9d5a9c065b58e429a99;hpb=da799981f5373b09398319df12e77e2efc75caa6 diff --git a/resources/libraries/python/PapiExecutor.py b/resources/libraries/python/PapiExecutor.py index ad0de27b82..ecee70c9c5 100644 --- a/resources/libraries/python/PapiExecutor.py +++ b/resources/libraries/python/PapiExecutor.py @@ -1,4 +1,4 @@ -# Copyright (c) 2018 Cisco and/or its affiliates. +# Copyright (c) 2021 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: @@ -11,214 +11,1043 @@ # See the License for the specific language governing permissions and # limitations under the License. -"""Python API executor library.""" +"""Python API executor library. +""" -import binascii +import copy +import glob import json +import shutil +import struct # vpp-papi can raise struct.error +import subprocess +import sys +import tempfile +import time +from collections import UserDict -from paramiko.ssh_exception import SSHException + +from pprint import pformat from robot.api import logger from resources.libraries.python.Constants import Constants -from resources.libraries.python.PapiErrors import PapiInitError, \ - PapiJsonFileError, PapiCommandError, PapiCommandInputError -# TODO: from resources.libraries.python.PapiHistory import PapiHistory -from resources.libraries.python.ssh import SSH, SSHTimeout +from resources.libraries.python.LocalExecution import run +from resources.libraries.python.FilteredLogger import FilteredLogger +from resources.libraries.python.PapiHistory import PapiHistory +from resources.libraries.python.ssh import ( + SSH, SSHTimeout, exec_cmd_no_error, scp_node) +from resources.libraries.python.topology import Topology, SocketType +from resources.libraries.python.VppApiCrc import VppApiCrcChecker -__all__ = ['PapiExecutor'] +__all__ = [ + u"PapiExecutor", + u"PapiSocketExecutor", + u"Disconnector", +] -class PapiExecutor(object): - """Contains methods for executing Python API commands on DUTs.""" - def __init__(self, node): - self._stdout = None - self._stderr = None - self._ret_code = None +def dictize(obj): + """A helper method, to make namedtuple-like object accessible as dict. + + If the object is namedtuple-like, its _asdict() form is returned, + but in the returned object __getitem__ method is wrapped + to dictize also any items returned. + If the object does not have _asdict, it will be returned without any change. + Integer keys still access the object as tuple. + + A more useful version would be to keep obj mostly as a namedtuple, + just add getitem for string keys. Unfortunately, namedtuple inherits + from tuple, including its read-only __getitem__ attribute, + so we cannot monkey-patch it. + + TODO: Create a proxy for named tuple to allow that. + + :param obj: Arbitrary object to dictize. + :type obj: object + :returns: Dictized object. + :rtype: same as obj type or collections.OrderedDict + """ + if not hasattr(obj, u"_asdict"): + return obj + overriden = UserDict(obj._asdict()) + old_get = overriden.__getitem__ + new_get = lambda self, key: dictize(old_get(self, key)) + overriden.__getitem__ = new_get + return overriden + + +class PapiSocketExecutor: + """Methods for executing VPP Python API commands on forwarded socket. + + Previously, we used an implementation with single client instance + and connection being handled by a resource manager. + On "with" statement, the instance connected, and disconnected + on exit from the "with" block. + This was limiting (no nested with blocks) and mainly it was slow: + 0.7 seconds per disconnect cycle on Skylake, more than 3 second on Taishan. + + The currently used implementation caches the connected client instances, + providing speedup and making "with" blocks unnecessary. + But with many call sites, "with" blocks are still the main usage pattern. + Documentation still lists that as the intended pattern. + + As a downside, clients need to be explicitly told to disconnect + before VPP restart. + There is some amount of retries and disconnects on disconnect + (so unresponsive VPPs do not breach test much more than needed), + but it is hard to verify all that works correctly. + Especially, if Robot crashes, files and ssh processes may leak. + + Delay for accepting socket connection is 10s. + TODO: Decrease 10s to value that is long enough for creating connection + and short enough to not affect performance. + + The current implementation downloads and parses .api.json files only once + and caches client instances for reuse. + Cleanup metadata is added as additional attributes + directly to client instances. + + The current implementation seems to run into read error occasionally. + Not sure if the error is in Python code on Robot side, ssh forwarding, + or socket handling at VPP side. Anyway, reconnect after some sleep + seems to help, hoping repeated command execution does not lead to surprises. + The reconnection is logged at WARN level, so it is prominently shown + in log.html, so we can see how frequently it happens. + + TODO: Support handling of retval!=0 without try/except in caller. + + Note: Use only with "with" statement, e.g.: + + cmd = 'show_version' + with PapiSocketExecutor(node) as papi_exec: + reply = papi_exec.add(cmd).get_reply(err_msg) + + This class processes two classes of VPP PAPI methods: + 1. Simple request / reply: method='request'. + 2. Dump functions: method='dump'. + + Note that access to VPP stats over socket is not supported yet. + + The recommended ways of use are (examples): + + 1. Simple request / reply + + a. One request with no arguments: + + cmd = 'show_version' + with PapiSocketExecutor(node) as papi_exec: + reply = papi_exec.add(cmd).get_reply(err_msg) + + b. Three requests with arguments, the second and the third ones are the same + but with different arguments. + + with PapiSocketExecutor(node) as papi_exec: + replies = papi_exec.add(cmd1, **args1).add(cmd2, **args2).\ + add(cmd2, **args3).get_replies(err_msg) + + 2. Dump functions + + cmd = 'sw_interface_rx_placement_dump' + with PapiSocketExecutor(node) as papi_exec: + details = papi_exec.add(cmd, sw_if_index=ifc['vpp_sw_index']).\ + get_details(err_msg) + """ + + # Class cache for reuse between instances. + api_root_dir = None + """We copy .api json files and PAPI code from DUT to robot machine. + This class variable holds temporary directory once created. + When python exits, the directory is deleted, so no downloaded file leaks. + The value will be set to TemporaryDirectory class instance (not string path) + to ensure deletion at exit.""" + api_json_path = None + """String path to .api.json files, a directory somewhere in api_root_dir.""" + api_package_path = None + """String path to PAPI code, a different directory under api_root_dir.""" + crc_checker = None + """Accesses .api.json files at creation, caching speeds up accessing it.""" + reusable_vpp_client_list = list() + """Each connection needs a separate client instance, + and each client instance creation needs to parse all .api files, + which takes time. If a client instance disconnects, it is put here, + so on next connect we can reuse intead of creating new.""" + conn_cache = dict() + """Mapping from node key to connected client instance.""" + + def __init__(self, node, remote_vpp_socket=Constants.SOCKSVR_PATH): + """Store the given arguments, declare managed variables. + + :param node: Node to connect to and forward unix domain socket from. + :param remote_vpp_socket: Path to remote socket to tunnel to. + :type node: dict + :type remote_vpp_socket: str + """ self._node = node - self._json_data = None - self._api_reply = list() - self._api_data = None + self._remote_vpp_socket = remote_vpp_socket + # The list of PAPI commands to be executed on the node. + self._api_command_list = list() - self._ssh = SSH() + def ensure_api_dirs(self): + """Copy files from DUT to local temporary directory. + + If the directory is still there, do not copy again. + If copying, also initialize CRC checker (this also performs + static checks), and remember PAPI package path. + Do not add that to PATH yet. + """ + cls = self.__class__ + if cls.api_package_path: + return + cls.api_root_dir = tempfile.TemporaryDirectory(dir=u"/tmp") + root_path = cls.api_root_dir.name + # Pack, copy and unpack Python part of VPP installation from _node. + # TODO: Use rsync or recursive version of ssh.scp_node instead? + node = self._node + exec_cmd_no_error(node, [u"rm", u"-rf", u"/tmp/papi.txz"]) + # Papi python version depends on OS (and time). + # Python 2.7 or 3.4, site-packages or dist-packages. + installed_papi_glob = u"/usr/lib/python3*/*-packages/vpp_papi" + # We need to wrap this command in bash, in order to expand globs, + # and as ssh does join, the inner command has to be quoted. + inner_cmd = u" ".join([ + u"tar", u"cJf", u"/tmp/papi.txz", u"--exclude=*.pyc", + installed_papi_glob, u"/usr/share/vpp/api" + ]) + exec_cmd_no_error(node, [u"bash", u"-c", u"'" + inner_cmd + u"'"]) + scp_node(node, root_path + u"/papi.txz", u"/tmp/papi.txz", get=True) + run([u"tar", u"xf", root_path + u"/papi.txz", u"-C", root_path]) + cls.api_json_path = root_path + u"/usr/share/vpp/api" + # Perform initial checks before .api.json files are gone, + # by creating the checker instance. + cls.crc_checker = VppApiCrcChecker(cls.api_json_path) + # When present locally, we finally can find the installation path. + cls.api_package_path = glob.glob(root_path + installed_papi_glob)[0] + # Package path has to be one level above the vpp_papi directory. + cls.api_package_path = cls.api_package_path.rsplit(u"/", 1)[0] + + def ensure_vpp_instance(self): + """Create or reuse a closed client instance, return it. + + The instance is initialized for unix domain socket access, + it has initialized all the bindings, it is removed from the internal + list of disconnected instances, but it is not connected + (to a local socket) yet. + + :returns: VPP client instance ready for connect. + :rtype: vpp_papi.VPPApiClient + """ + self.ensure_api_dirs() + cls = self.__class__ + if cls.reusable_vpp_client_list: + # Reuse in LIFO fashion. + *cls.reusable_vpp_client_list, ret = cls.reusable_vpp_client_list + return ret + # Creating an instance leads to dynamic imports from VPP PAPI code, + # so the package directory has to be present until the instance. + # But it is simpler to keep the package dir around. try: - self._ssh.connect(node) - except: - raise SSHException('Cannot open SSH connection to host {host} to ' - 'execute PAPI command(s)'. - format(host=self._node['host'])) + sys.path.append(cls.api_package_path) + # TODO: Pylint says import-outside-toplevel and import-error. + # It is right, we should refactor the code and move initialization + # of package outside. + from vpp_papi.vpp_papi import VPPApiClient as vpp_class + vpp_class.apidir = cls.api_json_path + # We need to create instance before removing from sys.path. + vpp_instance = vpp_class( + use_socket=True, server_address=u"TBD", async_thread=False, + read_timeout=14, logger=FilteredLogger(logger, u"INFO") + ) + # Cannot use loglevel parameter, robot.api.logger lacks support. + # TODO: Stop overriding read_timeout when VPP-1722 is fixed. + finally: + if sys.path[-1] == cls.api_package_path: + sys.path.pop() + return vpp_instance + + @classmethod + def key_for_node_and_socket(cls, node, remote_socket): + """Return a hashable object to distinguish nodes. + + The usual node object (of "dict" type) is not hashable, + and can contain mutable information (mostly virtual interfaces). + Use this method to get an object suitable for being a key in dict. + + The fields to include are chosen by what ssh needs. + + This class method is needed, for disconnect. + + :param node: The node object to distinguish. + :param remote_socket: Path to remote socket. + :type node: dict + :type remote_socket: str + :return: Tuple of values distinguishing this node from similar ones. + :rtype: tuple of str + """ + return ( + node[u"host"], + node[u"port"], + remote_socket, + # TODO: Do we support sockets paths such as "~/vpp/api.socket"? + # If yes, add also: + # node[u"username"], + ) + + def key_for_self(self): + """Return a hashable object to distinguish nodes. + + Just a wrapper around key_for_node_and_socket + which sets up proper arguments. + + :return: Tuple of values distinguishing this node from similar ones. + :rtype: tuple of str + """ + return self.__class__.key_for_node_and_socket( + self._node, self._remote_vpp_socket, + ) + + def set_connected_client(self, client): + """Add a connected client instance into cache. + + This hides details of what the node key is. + + If there already is a client for the computed key, + fail, as it is a sign of resource leakage. + + :param client: VPP client instance in connected state. + :type client: vpp_papi.VPPApiClient + :raises RuntimeError: If related key already has a cached client. + """ + key = self.key_for_self() + cache = self.__class__.conn_cache + if key in cache: + raise RuntimeError(f"Caching client with existing key: {key}") + cache[key] = client + + def get_connected_client(self, check_connected=True): + """Return None or cached connected client. + + If check_connected, RuntimeError is raised when the client is + not in cache. None is returned if client is not in cache + (and the check is disabled). + + This hides details of what the node key is. + + :param check_connected: Whether cache miss raises. + :type check_connected: bool + :returns: Connected client instance, or None if uncached and no check. + :rtype: Optional[vpp_papi.VPPApiClient] + :raises RuntimeError: If cache miss and check enabled. + """ + key = self.key_for_self() + ret = self.__class__.conn_cache.get(key, None) + + if ret is None: + if check_connected: + raise RuntimeError(f"Client not cached for key: {key}") + else: + # When reading logs, it is good to see which VPP is accessed. + logger.debug(f"Activated cached PAPI client for key: {key}") + return ret def __enter__(self): + """Create a tunnel, connect VPP instance. + + If the connected client is in cache, return it. + Only if not, create a new (or reuse a disconnected) client instance. + + Only at this point a local socket names are created + in a temporary directory, as CSIT can connect to multiple VPPs. + + The following attributes are added to the client instance + to simplify caching and cleanup: + csit_temp_dir + - Temporary socket files are created here. + csit_control_socket + - This socket controls the local ssh process doing the forwarding. + csit_local_vpp_socket + - This is the forwarded socket to talk with remote VPP. + + The attribute names do not start with underscore, + so pylint does not complain about accessing private attribute. + The attribute names start with csit_ to avoid naming conflicts + with "real" attributes from VPP Python code. + + :returns: self + :rtype: PapiSocketExecutor + """ + # Do we have the connected instance in the cache? + vpp_instance = self.get_connected_client(check_connected=False) + if vpp_instance is not None: + return self + # No luck, create and connect a new instance. + time_enter = time.time() + node = self._node + # Parsing takes longer than connecting, prepare instance before tunnel. + vpp_instance = self.ensure_vpp_instance() + # Store into cache as soon as possible. + # If connection fails, it is better to attempt disconnect anyway. + self.set_connected_client(vpp_instance) + # Set additional attributes. + vpp_instance.csit_temp_dir = tempfile.TemporaryDirectory(dir=u"/tmp") + temp_path = vpp_instance.csit_temp_dir.name + api_socket = temp_path + u"/vpp-api.sock" + vpp_instance.csit_local_vpp_socket = api_socket + ssh_socket = temp_path + u"/ssh.sock" + vpp_instance.csit_control_socket = ssh_socket + # Cleanup possibilities. + ret_code, _ = run([u"ls", ssh_socket], check=False) + if ret_code != 2: + # This branch never seems to be hit in CI, + # but may be useful when testing manually. + run( + [u"ssh", u"-S", ssh_socket, u"-O", u"exit", u"0.0.0.0"], + check=False, log=True + ) + # TODO: Is any sleep necessary? How to prove if not? + run([u"sleep", u"0.1"]) + run([u"rm", u"-vrf", ssh_socket]) + # Even if ssh can perhaps reuse this file, + # we need to remove it for readiness detection to work correctly. + run([u"rm", u"-rvf", api_socket]) + # We use sleep command. The ssh command will exit in 30 second, + # unless a local socket connection is established, + # in which case the ssh command will exit only when + # the ssh connection is closed again (via control socket). + # The log level is to suppress "Warning: Permanently added" messages. + ssh_cmd = [ + u"ssh", u"-S", ssh_socket, u"-M", u"-L", + api_socket + u":" + self._remote_vpp_socket, + u"-p", str(node[u"port"]), + u"-o", u"LogLevel=ERROR", + u"-o", u"UserKnownHostsFile=/dev/null", + u"-o", u"StrictHostKeyChecking=no", + u"-o", u"ExitOnForwardFailure=yes", + node[u"username"] + u"@" + node[u"host"], + u"sleep", u"30" + ] + priv_key = node.get(u"priv_key") + if priv_key: + # This is tricky. We need a file to pass the value to ssh command. + # And we need ssh command, because paramiko does not support sockets + # (neither ssh_socket, nor _remote_vpp_socket). + key_file = tempfile.NamedTemporaryFile() + key_file.write(priv_key) + # Make sure the content is written, but do not close yet. + key_file.flush() + ssh_cmd[1:1] = [u"-i", key_file.name] + password = node.get(u"password") + if password: + # Prepend sshpass command to set password. + ssh_cmd[:0] = [u"sshpass", u"-p", password] + time_stop = time.time() + 10.0 + # subprocess.Popen seems to be the best way to run commands + # on background. Other ways (shell=True with "&" and ssh with -f) + # seem to be too dependent on shell behavior. + # In particular, -f does NOT return values for run(). + subprocess.Popen(ssh_cmd) + # Check socket presence on local side. + while time.time() < time_stop: + # It can take a moment for ssh to create the socket file. + ret_code, _ = run( + [u"ls", u"-l", api_socket], check=False + ) + if not ret_code: + break + time.sleep(0.1) + else: + raise RuntimeError(u"Local side socket has not appeared.") + if priv_key: + # Socket up means the key has been read. Delete file by closing it. + key_file.close() + # Everything is ready, set the local socket address and connect. + vpp_instance.transport.server_address = api_socket + # It seems we can get read error even if every preceding check passed. + # Single retry seems to help. + for _ in range(2): + try: + vpp_instance.connect_sync(u"csit_socket") + except (IOError, struct.error) as err: + logger.warn(f"Got initial connect error {err!r}") + vpp_instance.disconnect() + else: + break + else: + raise RuntimeError(u"Failed to connect to VPP over a socket.") + logger.trace( + f"Establishing socket connection took {time.time()-time_enter}s" + ) return self def __exit__(self, exc_type, exc_val, exc_tb): - pass + """No-op, the client instance remains in cache in connected state.""" - @staticmethod - def _process_api_data(api_d): - """Process API data for smooth converting to JSON string. + @classmethod + def disconnect_by_key(cls, key): + """Disconnect a connected client instance, noop it not connected. - Apply binascii.hexlify() method for string values. + Also remove the local sockets by deleting the temporary directory. + Put disconnected client instances to the reuse list. + The added attributes are not cleaned up, + as their values will get overwritten on next connect. - :param api_d: List of APIs with their arguments. - :type api_d: list - :returns: List of APIs with arguments pre-processed for JSON. - :rtype: list + This method is useful for disconnect_all type of work. + + :param key: Tuple identifying the node (and socket). + :type key: tuple of str """ + client_instance = cls.conn_cache.get(key, None) + if client_instance is None: + return + logger.debug(f"Disconnecting by key: {key}") + client_instance.disconnect() + run([ + u"ssh", u"-S", client_instance.csit_control_socket, u"-O", + u"exit", u"0.0.0.0" + ], check=False) + # Temp dir has autoclean, but deleting explicitly + # as an error can happen. + try: + client_instance.csit_temp_dir.cleanup() + except FileNotFoundError: + # There is a race condition with ssh removing its ssh.sock file. + # Single retry should be enough to ensure the complete removal. + shutil.rmtree(client_instance.csit_temp_dir.name) + # Finally, put disconnected clients to reuse list. + cls.reusable_vpp_client_list.append(client_instance) + # Invalidate cache last. Repeated errors are better than silent leaks. + del cls.conn_cache[key] - api_data_processed = list() - for api in api_d: - api_name = api['api_name'] - api_args = api['api_args'] - api_processed = dict(api_name=api_name) - api_args_processed = dict() - for a_k, a_v in api_args.iteritems(): - value = binascii.hexlify(a_v) if isinstance(a_v, str) else a_v - api_args_processed[str(a_k)] = value - api_processed['api_args'] = api_args_processed - api_data_processed.append(api_processed) - return api_data_processed + @classmethod + def disconnect_by_node_and_socket( + cls, node, remote_socket=Constants.SOCKSVR_PATH + ): + """Disconnect a connected client instance, noop it not connected. + + Also remove the local sockets by deleting the temporary directory. + Put disconnected client instances to the reuse list. + The added attributes are not cleaned up, + as their values will get overwritten on next connect. + + Call this method just before killing/restarting remote VPP instance. + """ + key = cls.key_for_node_and_socket(node, remote_socket) + return cls.disconnect_by_key(key) + + @classmethod + def disconnect_all_sockets_by_node(cls, node): + """Disconnect all socket connected client instance. + + Noop if not connected. + + Also remove the local sockets by deleting the temporary directory. + Put disconnected client instances to the reuse list. + The added attributes are not cleaned up, + as their values will get overwritten on next connect. + + Call this method just before killing/restarting remote VPP instance. + """ + sockets = Topology.get_node_sockets(node, socket_type=SocketType.PAPI) + if sockets: + for socket in sockets.values(): + # TODO: Remove sockets from topology. + PapiSocketExecutor.disconnect_by_node_and_socket(node, socket) + # Always attempt to disconnect the default socket. + return cls.disconnect_by_node_and_socket(node) @staticmethod - def _revert_api_reply(api_r): - """Process API reply / a part of API reply. + def disconnect_all_papi_connections(): + """Disconnect all connected client instances, tear down the SSH tunnels. + + Also remove the local sockets by deleting the temporary directory. + Put disconnected client instances to the reuse list. + The added attributes are not cleaned up, + as their values will get overwritten on next connect. + + This should be a class method, + but we prefer to call static methods from Robot. + + Call this method just before killing/restarting all VPP instances. + """ + cls = PapiSocketExecutor + # Iterate over copy of entries so deletions do not mess with iterator. + keys_copy = list(cls.conn_cache.keys()) + for key in keys_copy: + cls.disconnect_by_key(key) + + def add(self, csit_papi_command, history=True, **kwargs): + """Add next command to internal command list; return self. + + Unless disabled, new entry to papi history is also added at this point. + The argument name 'csit_papi_command' must be unique enough as it cannot + be repeated in kwargs. + The kwargs dict is deep-copied, so it is safe to use the original + with partial modifications for subsequent commands. + + Any pending conflicts from .api.json processing are raised. + Then the command name is checked for known CRCs. + Unsupported commands raise an exception, as CSIT change + should not start using messages without making sure which CRCs + are supported. + Each CRC issue is raised only once, so subsequent tests + can raise other issues. - Apply binascii.unhexlify() method for unicode values. + :param csit_papi_command: VPP API command. + :param history: Enable/disable adding command to PAPI command history. + :param kwargs: Optional key-value arguments. + :type csit_papi_command: str + :type history: bool + :type kwargs: dict + :returns: self, so that method chaining is possible. + :rtype: PapiSocketExecutor + :raises RuntimeError: If unverified or conflicting CRC is encountered. + """ + self.crc_checker.report_initial_conflicts() + if history: + PapiHistory.add_to_papi_history( + self._node, csit_papi_command, **kwargs + ) + self.crc_checker.check_api_name(csit_papi_command) + self._api_command_list.append( + dict( + api_name=csit_papi_command, + api_args=copy.deepcopy(kwargs) + ) + ) + return self + + def get_replies(self, err_msg="Failed to get replies."): + """Get replies from VPP Python API. + + The replies are parsed into dict-like objects, + "retval" field is guaranteed to be zero on success. + + :param err_msg: The message used if the PAPI command(s) execution fails. + :type err_msg: str + :returns: Responses, dict objects with fields due to API and "retval". + :rtype: list of dict + :raises RuntimeError: If retval is nonzero, parsing or ssh error. + """ + return self._execute(err_msg=err_msg) + + def get_reply(self, err_msg=u"Failed to get reply."): + """Get reply from VPP Python API. - :param api_r: API reply. - :type api_r: dict - :returns: Processed API reply / a part of API reply. + The reply is parsed into dict-like object, + "retval" field is guaranteed to be zero on success. + + TODO: Discuss exception types to raise, unify with inner methods. + + :param err_msg: The message used if the PAPI command(s) execution fails. + :type err_msg: str + :returns: Response, dict object with fields due to API and "retval". :rtype: dict + :raises AssertionError: If retval is nonzero, parsing or ssh error. """ + replies = self.get_replies(err_msg=err_msg) + if len(replies) != 1: + raise RuntimeError(f"Expected single reply, got {replies!r}") + return replies[0] + + def get_sw_if_index(self, err_msg=u"Failed to get reply."): + """Get sw_if_index from reply from VPP Python API. - reply_dict = dict() - reply_value = dict() - for reply_key, reply_v in api_r.iteritems(): - for a_k, a_v in reply_v.iteritems(): - # value = binascii.unhexlify(a_v) if isinstance(a_v, unicode) \ - # else a_v - # reply_value[a_k] = value - reply_value[a_k] = a_v - reply_dict[reply_key] = reply_value - return reply_dict + Frequently, the caller is only interested in sw_if_index field + of the reply, this wrapper makes such call sites shorter. - def _process_reply(self, api_reply): - """Process API reply. + TODO: Discuss exception types to raise, unify with inner methods. - :param api_reply: API reply. - :type api_reply: dict or list of dict - :returns: Processed API reply. - :rtype: list or dict + :param err_msg: The message used if the PAPI command(s) execution fails. + :type err_msg: str + :returns: Response, sw_if_index value of the reply. + :rtype: int + :raises AssertionError: If retval is nonzero, parsing or ssh error. """ + reply = self.get_reply(err_msg=err_msg) + logger.trace(f"Getting index from {reply!r}") + return reply[u"sw_if_index"] - if isinstance(api_reply, list): - reverted_reply = list() - for a_r in api_reply: - reverted_reply.append(self._revert_api_reply(a_r)) - else: - reverted_reply = self._revert_api_reply(api_reply) - return reverted_reply + def get_details(self, err_msg="Failed to get dump details."): + """Get dump details from VPP Python API. - def _process_json_data(self): - """Process received JSON data.""" + The details are parsed into dict-like objects. + The number of details per single dump command can vary, + and all association between details and dumps is lost, + so if you care about the association (as opposed to + logging everything at once for debugging purposes), + it is recommended to call get_details for each dump (type) separately. - for data in self._json_data: - api_name = data['api_name'] - api_reply = data['api_reply'] - api_reply_processed = dict( - api_name=api_name, api_reply=self._process_reply(api_reply)) - self._api_reply.append(api_reply_processed) + :param err_msg: The message used if the PAPI command(s) execution fails. + :type err_msg: str + :returns: Details, dict objects with fields due to API without "retval". + :rtype: list of dict + """ + return self._execute(err_msg) - def execute_papi(self, api_data, timeout=120): - """Execute PAPI command(s) on remote node and store the result. + @staticmethod + def run_cli_cmd( + node, cli_cmd, log=True, remote_vpp_socket=Constants.SOCKSVR_PATH): + """Run a CLI command as cli_inband, return the "reply" field of reply. - :param api_data: List of APIs with their arguments. - :param timeout: Timeout in seconds. - :type api_data: list - :type timeout: int - :raises SSHTimeout: If PAPI command(s) execution is timed out. - :raises PapiInitError: If PAPI initialization failed. - :raises PapiJsonFileError: If no api.json file found. - :raises PapiCommandError: If PAPI command(s) execution failed. - :raises PapiCommandInputError: If invalid attribute name or invalid - value is used in API call. - :raises RuntimeError: If PAPI executor failed due to another reason. + Optionally, log the field value. + + :param node: Node to run command on. + :param cli_cmd: The CLI command to be run on the node. + :param remote_vpp_socket: Path to remote socket to tunnel to. + :param log: If True, the response is logged. + :type node: dict + :type remote_vpp_socket: str + :type cli_cmd: str + :type log: bool + :returns: CLI output. + :rtype: str + """ + cmd = u"cli_inband" + args = dict( + cmd=cli_cmd + ) + err_msg = f"Failed to run 'cli_inband {cli_cmd}' PAPI command " \ + f"on host {node[u'host']}" + + with PapiSocketExecutor(node, remote_vpp_socket) as papi_exec: + reply = papi_exec.add(cmd, **args).get_reply(err_msg)["reply"] + if log: + logger.info( + f"{cli_cmd} ({node[u'host']} - {remote_vpp_socket}):\n" + f"{reply.strip()}" + ) + return reply + + @staticmethod + def run_cli_cmd_on_all_sockets(node, cli_cmd, log=True): + """Run a CLI command as cli_inband, on all sockets in topology file. + + :param node: Node to run command on. + :param cli_cmd: The CLI command to be run on the node. + :param log: If True, the response is logged. + :type node: dict + :type cli_cmd: str + :type log: bool """ - self._api_data = api_data - api_data_processed = self._process_api_data(api_data) - json_data = json.dumps(api_data_processed) + sockets = Topology.get_node_sockets(node, socket_type=SocketType.PAPI) + if sockets: + for socket in sockets.values(): + PapiSocketExecutor.run_cli_cmd( + node, cli_cmd, log=log, remote_vpp_socket=socket + ) + + @staticmethod + def dump_and_log(node, cmds): + """Dump and log requested information, return None. + + :param node: DUT node. + :param cmds: Dump commands to be executed. + :type node: dict + :type cmds: list of str + """ + with PapiSocketExecutor(node) as papi_exec: + for cmd in cmds: + dump = papi_exec.add(cmd).get_details() + logger.debug(f"{cmd}:\n{pformat(dump)}") + + def _execute(self, err_msg=u"Undefined error message", exp_rv=0): + """Turn internal command list into data and execute; return replies. + + This method also clears the internal command list. + + IMPORTANT! + Do not use this method in L1 keywords. Use: + - get_replies() + - get_reply() + - get_sw_if_index() + - get_details() + + :param err_msg: The message used if the PAPI command(s) execution fails. + :type err_msg: str + :returns: Papi responses parsed into a dict-like object, + with fields due to API (possibly including retval). + :rtype: list of dict + :raises RuntimeError: If the replies are not all correct. + """ + vpp_instance = self.get_connected_client() + local_list = self._api_command_list + # Clear first as execution may fail. + self._api_command_list = list() + replies = list() + for command in local_list: + api_name = command[u"api_name"] + papi_fn = getattr(vpp_instance.api, api_name) + try: + try: + reply = papi_fn(**command[u"api_args"]) + except (IOError, struct.error) as err: + # Occasionally an error happens, try reconnect. + logger.warn(f"Reconnect after error: {err!r}") + vpp_instance.disconnect() + # Testing shows immediate reconnect fails. + time.sleep(1) + vpp_instance.connect_sync(u"csit_socket") + logger.trace(u"Reconnected.") + reply = papi_fn(**command[u"api_args"]) + except (AttributeError, IOError, struct.error) as err: + raise AssertionError(err_msg) from err + # *_dump commands return list of objects, convert, ordinary reply. + if not isinstance(reply, list): + reply = [reply] + for item in reply: + message_name = item.__class__.__name__ + self.crc_checker.check_api_name(message_name) + dict_item = dictize(item) + if u"retval" in dict_item.keys(): + # *_details messages do not contain retval. + retval = dict_item[u"retval"] + if retval != exp_rv: + raise AssertionError( + f"Retval {retval!r} does not match expected " + f"retval {exp_rv!r} in message {message_name} " + f"for command {command}." + ) + replies.append(dict_item) + return replies + + +class Disconnector: + """Class for holding a single keyword.""" + + @staticmethod + def disconnect_all_papi_connections(): + """Disconnect all connected client instances, tear down the SSH tunnels. + + Also remove the local sockets by deleting the temporary directory. + Put disconnected client instances to the reuse list. + The added attributes are not cleaned up, + as their values will get overwritten on next connect. + + Call this method just before killing/restarting all VPP instances. + + This could be a class method of PapiSocketExecutor. + But Robot calls methods on instances, and it would be weird + to give node argument for constructor in import. + Also, as we have a class of the same name as the module, + the keywords defined on module level are not accessible. + """ + cls = PapiSocketExecutor + # Iterate over copy of entries so deletions do not mess with iterator. + keys_copy = list(cls.conn_cache.keys()) + for key in keys_copy: + cls.disconnect_by_key(key) + + +class PapiExecutor: + """Contains methods for executing VPP Python API commands on DUTs. + + TODO: Remove .add step, make get_stats accept paths directly. + + This class processes only one type of VPP PAPI methods: vpp-stats. + + The recommended ways of use are (examples): + + path = ['^/if', '/err/ip4-input', '/sys/node/ip4-input'] + with PapiExecutor(node) as papi_exec: + stats = papi_exec.add(api_name='vpp-stats', path=path).get_stats() + + print('RX interface core 0, sw_if_index 0:\n{0}'.\ + format(stats[0]['/if/rx'][0][0])) - cmd = "python {fw_dir}/{papi_provider} --json_data '{json}'".format( - fw_dir=Constants.REMOTE_FW_DIR, - papi_provider=Constants.RESOURCES_PAPI_PROVIDER, - json=json_data) + or + path_1 = ['^/if', ] + path_2 = ['^/if', '/err/ip4-input', '/sys/node/ip4-input'] + with PapiExecutor(node) as papi_exec: + stats = papi_exec.add('vpp-stats', path=path_1).\ + add('vpp-stats', path=path_2).get_stats() + + print('RX interface core 0, sw_if_index 0:\n{0}'.\ + format(stats[1]['/if/rx'][0][0])) + + Note: In this case, when PapiExecutor method 'add' is used: + - its parameter 'csit_papi_command' is used only to keep information + that vpp-stats are requested. It is not further processed but it is + included in the PAPI history this way: + vpp-stats(path=['^/if', '/err/ip4-input', '/sys/node/ip4-input']) + Always use csit_papi_command="vpp-stats" if the VPP PAPI method + is "stats". + - the second parameter must be 'path' as it is used by PapiExecutor + method 'add'. + - even if the parameter contains multiple paths, there is only one + reply item (for each .add). + """ + + def __init__(self, node): + """Initialization. + + :param node: Node to run command(s) on. + :type node: dict + """ + # Node to run command(s) on. + self._node = node + + # The list of PAPI commands to be executed on the node. + self._api_command_list = list() + + self._ssh = SSH() + + def __enter__(self): try: - ret_code, stdout, stderr = self._ssh.exec_command_sudo( - cmd=cmd, timeout=timeout) - except SSHTimeout: - logger.error('PAPI command(s) execution timeout on host {host}:' - '\n{apis}'.format(host=self._node['host'], - apis=self._api_data)) - raise - except (PapiInitError, PapiJsonFileError, PapiCommandError, - PapiCommandInputError): - logger.error('PAPI command(s) execution failed on host {host}'. - format(host=self._node['host'])) - raise - except: - raise RuntimeError('PAPI command(s) execution on host {host} ' - 'failed: {apis}'.format(host=self._node['host'], - apis=self._api_data)) + self._ssh.connect(self._node) + except IOError: + raise RuntimeError( + f"Cannot open SSH connection to host {self._node[u'host']} " + f"to execute PAPI command(s)" + ) + return self + + def __exit__(self, exc_type, exc_val, exc_tb): + self._ssh.disconnect(self._node) - self._ret_code = ret_code - self._stdout = stdout - self._stderr = stderr + def add(self, csit_papi_command=u"vpp-stats", history=True, **kwargs): + """Add next command to internal command list; return self. - def papi_should_have_failed(self): - """Read return code from last executed script and raise exception if the - PAPI command(s) didn't fail. + The argument name 'csit_papi_command' must be unique enough as it cannot + be repeated in kwargs. + The kwargs dict is deep-copied, so it is safe to use the original + with partial modifications for subsequent commands. - :raises RuntimeError: When no PAPI command executed. - :raises AssertionError: If PAPI command(s) execution passed. + :param csit_papi_command: VPP API command. + :param history: Enable/disable adding command to PAPI command history. + :param kwargs: Optional key-value arguments. + :type csit_papi_command: str + :type history: bool + :type kwargs: dict + :returns: self, so that method chaining is possible. + :rtype: PapiExecutor + """ + if history: + PapiHistory.add_to_papi_history( + self._node, csit_papi_command, **kwargs + ) + self._api_command_list.append( + dict( + api_name=csit_papi_command, api_args=copy.deepcopy(kwargs) + ) + ) + return self + + def get_stats( + self, err_msg=u"Failed to get statistics.", timeout=120, + socket=Constants.SOCKSTAT_PATH): + """Get VPP Stats from VPP Python API. + + :param err_msg: The message used if the PAPI command(s) execution fails. + :param timeout: Timeout in seconds. + :param socket: Path to Stats socket to tunnel to. + :type err_msg: str + :type timeout: int + :type socket: str + :returns: Requested VPP statistics. + :rtype: list of dict """ + paths = [cmd[u"api_args"][u"path"] for cmd in self._api_command_list] + self._api_command_list = list() - if self._ret_code is None: - raise RuntimeError("First execute the PAPI command(s)!") - if self._ret_code == 0: - raise AssertionError( - "PAPI command(s) execution passed, but failure was expected: " - "{apis}".format(apis=self._api_data)) + stdout = self._execute_papi( + paths, method=u"stats", err_msg=err_msg, timeout=timeout, + socket=socket + ) - def papi_should_have_passed(self): - """Read return code from last executed script and raise exception if the - PAPI command(s) failed. + return json.loads(stdout) - :raises RuntimeError: When no PAPI command executed. - :raises AssertionError: If PAPI command(s) execution failed. + @staticmethod + def _process_api_data(api_d): + """Process API data for smooth converting to JSON string. + + Apply binascii.hexlify() method for string values. + + :param api_d: List of APIs with their arguments. + :type api_d: list + :returns: List of APIs with arguments pre-processed for JSON. + :rtype: list """ - if self._ret_code is None: - raise RuntimeError("First execute the PAPI command(s)!") - if self._ret_code != 0: - raise AssertionError( - "PAPI command(s) execution failed, but success was expected: " - "{apis}".format(apis=self._api_data)) + def process_value(val): + """Process value. - def get_papi_stdout(self): - """Returns value of stdout from last executed PAPI command(s).""" + :param val: Value to be processed. + :type val: object + :returns: Processed value. + :rtype: dict or str or int + """ + if isinstance(val, dict): + for val_k, val_v in val.items(): + val[str(val_k)] = process_value(val_v) + retval = val + elif isinstance(val, list): + for idx, val_l in enumerate(val): + val[idx] = process_value(val_l) + retval = val + else: + retval = val.encode().hex() if isinstance(val, str) else val + return retval - return self._stdout + api_data_processed = list() + for api in api_d: + api_args_processed = dict() + for a_k, a_v in api[u"api_args"].items(): + api_args_processed[str(a_k)] = process_value(a_v) + api_data_processed.append( + dict( + api_name=api[u"api_name"], + api_args=api_args_processed + ) + ) + return api_data_processed - def get_papi_stderr(self): - """Returns value of stderr from last executed PAPI command(s).""" + def _execute_papi( + self, api_data, method=u"request", err_msg=u"", timeout=120, + socket=None): + """Execute PAPI command(s) on remote node and store the result. - return self._stderr + :param api_data: List of APIs with their arguments. + :param method: VPP Python API method. Supported methods are: 'request', + 'dump' and 'stats'. + :param err_msg: The message used if the PAPI command(s) execution fails. + :param timeout: Timeout in seconds. + :type api_data: list + :type method: str + :type err_msg: str + :type timeout: int + :returns: Stdout from remote python utility, to be parsed by caller. + :rtype: str + :raises SSHTimeout: If PAPI command(s) execution has timed out. + :raises RuntimeError: If PAPI executor failed due to another reason. + :raises AssertionError: If PAPI command(s) execution has failed. + """ + if not api_data: + raise RuntimeError(u"No API data provided.") - def get_papi_reply(self): - """Returns api reply from last executed PAPI command(s).""" + json_data = json.dumps(api_data) \ + if method in (u"stats", u"stats_request") \ + else json.dumps(self._process_api_data(api_data)) - self._json_data = json.loads(self._stdout) - self._process_json_data() + sock = f" --socket {socket}" if socket else u"" + cmd = f"{Constants.REMOTE_FW_DIR}/{Constants.RESOURCES_PAPI_PROVIDER}" \ + f" --method {method} --data '{json_data}'{sock}" + try: + ret_code, stdout, _ = self._ssh.exec_command_sudo( + cmd=cmd, timeout=timeout, log_stdout_err=False + ) + # TODO: Fail on non-empty stderr? + except SSHTimeout: + logger.error( + f"PAPI command(s) execution timeout on host " + f"{self._node[u'host']}:\n{api_data}" + ) + raise + except Exception as exc: + raise RuntimeError( + f"PAPI command(s) execution on host {self._node[u'host']} " + f"failed: {api_data}" + ) from exc + if ret_code != 0: + raise AssertionError(err_msg) - return self._api_reply + return stdout