CSIT-1450: PAPI executor

Change-Id: I4c756cc4b29901184594a728f6184c30cadd9c1a
Signed-off-by: Vratko Polak <vrpolak@cisco.com>

1 files changed, 245 insertions, 111 deletions

diff --git a/resources/libraries/python/PapiExecutor.py b/resources/libraries/python/PapiExecutor.py
index ad0de27b82..0313284405 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) 2019 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:
@@ -16,43 +16,248 @@
 import binascii
 import json
 
-from paramiko.ssh_exception import SSHException
 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
 
-__all__ = ['PapiExecutor']
+__all__ = ["PapiExecutor", "PapiResponse"]
+
+# TODO: Implement Papi History
+# from resources.libraries.python.PapiHistory import PapiHistory
+
+
+class PapiResponse(object):
+    """Class for metadata specifying the Papi reply, stdout, stderr and return
+    code.
+    """
+
+    def __init__(self, papi_reply=None, stdout="", stderr="", ret_code=None):
+        """Construct the Papi response by setting the values needed.
+
+        :param papi_reply: API reply from last executed PAPI command(s).
+        :param stdout: stdout from last executed PAPI command(s).
+        :param stderr: stderr from last executed PAPI command(s).
+        :param ret_code: ret_code from last executed PAPI command(s).
+        :type papi_reply: list
+        :type stdout: str
+        :type stderr: str
+        :type ret_code: int
+        """
+
+        # API reply from last executed PAPI command(s)
+        self.reply = papi_reply
+
+        # stdout from last executed PAPI command(s)
+        self.stdout = stdout
+
+        # stderr from last executed PAPI command(s).
+        self.stderr = stderr
+
+        # return code from last executed PAPI command(s)
+        self.ret_code = ret_code
+
+    def __str__(self):
+        """Return string with human readable description of the group.
+
+        :returns: Readable description.
+        :rtype: str
+        """
+        return ("papi_reply={papi_reply} "
+                "stdout={stdout} "
+                "stderr={stderr} "
+                "ret_code={ret_code}".
+                format(papi_reply=self.reply,
+                       stdout=self.stdout,
+                       stderr=self.stderr,
+                       ret_code=self.ret_code))
+
+    def __repr__(self):
+        """Return string executable as Python constructor call.
+
+        :returns: Executable constructor call.
+        :rtype: str
+        """
+        return ("PapiResponse(papi_reply={papi_reply} "
+                "stdout={stdout} "
+                "stderr={stderr} "
+                "ret_code={ret_code})".
+                format(papi_reply=self.reply,
+                       stdout=self.stdout,
+                       stderr=self.stderr,
+                       ret_code=self.ret_code))
 
 
 class PapiExecutor(object):
-    """Contains methods for executing Python API commands on DUTs."""
+    """Contains methods for executing Python API commands on DUTs.
+
+    Use only with "with" statement, e.g.:
+
+    with PapiExecutor(node) as papi_exec:
+        papi_resp = papi_exec.add('show_version').execute_should_pass(err_msg)
+    """
 
     def __init__(self, node):
-        self._stdout = None
-        self._stderr = None
-        self._ret_code = None
+        """Initialization.
+
+        :param node: Node to run command(s) on.
+        :type node: dict
+        """
+
+        # Node to run command(s) on.
         self._node = node
-        self._json_data = None
-        self._api_reply = list()
-        self._api_data = None
+
+        # The list of PAPI commands to be executed on the node.
+        self._api_command_list = list()
+
+        # The response on the PAPI commands.
+        self.response = PapiResponse()
 
         self._ssh = SSH()
-        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']))
 
     def __enter__(self):
+        try:
+            self._ssh.connect(self._node)
+        except IOError:
+            raise RuntimeError("Cannot open SSH connection to host {host} to "
+                               "execute PAPI command(s)".
+                               format(host=self._node["host"]))
         return self
 
     def __exit__(self, exc_type, exc_val, exc_tb):
-        pass
+        self._ssh.disconnect(self._node)
+
+    def clear(self):
+        """Empty the internal command list; return self.
+
+        Use when not sure whether previous usage has left something in the list.
+
+        :returns: self, so that method chaining is possible.
+        :rtype: PapiExecutor
+        """
+        self._api_command_list = list()
+        return self
+
+    def add(self, command, **kwargs):
+        """Add next command to internal command list; return self.
+
+        :param command: VPP API command.
+        :param kwargs: Optional key-value arguments.
+        :type command: str
+        :type kwargs: dict
+        :returns: self, so that method chaining is possible.
+        :rtype: PapiExecutor
+        """
+        self._api_command_list.append(dict(api_name=command, api_args=kwargs))
+        return self
+
+    def execute(self, process_reply=True, ignore_errors=False, timeout=120):
+        """Turn internal command list into proper data and execute; return
+        PAPI response.
+
+        This method also clears the internal command list.
+
+        :param process_reply: Process PAPI reply if True.
+        :param ignore_errors: If true, the errors in the reply are ignored.
+        :param timeout: Timeout in seconds.
+        :type process_reply: bool
+        :type ignore_errors: bool
+        :type timeout: int
+        :returns: Papi response including: papi reply, stdout, stderr and
+            return code.
+        :rtype: PapiResponse
+        :raises KeyError: If the reply is not correct.
+        """
+
+        local_list = self._api_command_list
+
+        # Clear first as execution may fail.
+        self.clear()
+
+        ret_code, stdout, stderr = self._execute_papi(local_list, timeout)
+
+        papi_reply = list()
+        if process_reply:
+            json_data = json.loads(stdout)
+            for data in json_data:
+                try:
+                    api_reply_processed = dict(
+                        api_name=data["api_name"],
+                        api_reply=self._process_reply(data["api_reply"]))
+                except KeyError:
+                    if ignore_errors:
+                        continue
+                    else:
+                        raise
+                papi_reply.append(api_reply_processed)
+
+        return PapiResponse(papi_reply=papi_reply,
+                            stdout=stdout,
+                            stderr=stderr,
+                            ret_code=ret_code)
+
+    def execute_should_pass(self, err_msg="Failed to execute PAPI command.",
+                            process_reply=True, ignore_errors=False,
+                            timeout=120):
+        """Execute the PAPI commands and check the return code.
+        Raise exception if the PAPI command(s) failed.
+
+        Note: There are two exceptions raised to distinguish two situations. If
+        not needed, re-implement using only RuntimeError.
+
+        :param err_msg: The message used if the PAPI command(s) execution fails.
+        :param process_reply: Indicate whether or not to process PAPI reply.
+        :param ignore_errors: If true, the errors in the reply are ignored.
+        :param timeout: Timeout in seconds.
+        :type err_msg: str
+        :type process_reply: bool
+        :type ignore_errors: bool
+        :type timeout: int
+        :returns: Papi response including: papi reply, stdout, stderr and
+            return code.
+        :rtype: PapiResponse
+        :raises RuntimeError: If no PAPI command(s) executed.
+        :raises AssertionError: If PAPI command(s) execution passed.
+        """
+
+        response = self.execute(process_reply=process_reply,
+                                ignore_errors=ignore_errors,
+                                timeout=timeout)
+
+        if response.ret_code != 0:
+            raise AssertionError(err_msg)
+        return response
+
+    def execute_should_fail(self,
+                            err_msg="Execution of PAPI command did not fail.",
+                            process_reply=False, ignore_errors=False,
+                            timeout=120):
+        """Execute the PAPI commands and check the return code.
+        Raise exception if the PAPI command(s) did not fail.
+
+        It does not return anything as we expect it fails.
+
+        Note: There are two exceptions raised to distinguish two situations. If
+        not needed, re-implement using only RuntimeError.
+
+        :param err_msg: The message used if the PAPI command(s) execution fails.
+        :param process_reply: Indicate whether or not to process PAPI reply.
+        :param ignore_errors: If true, the errors in the reply are ignored.
+        :param timeout: Timeout in seconds.
+        :type err_msg: str
+        :type process_reply: bool
+        :type ignore_errors: bool
+        :type timeout: int
+        :raises RuntimeError: If no PAPI command(s) executed.
+        :raises AssertionError: If PAPI command(s) execution passed.
+        """
+
+        response = self.execute(process_reply=process_reply,
+                                ignore_errors=ignore_errors,
+                                timeout=timeout)
+
+        if response.ret_code == 0:
+            raise AssertionError(err_msg)
 
     @staticmethod
     def _process_api_data(api_d):
@@ -68,15 +273,12 @@ class PapiExecutor(object):
 
         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():
+            for a_k, a_v in api["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)
+            api_data_processed.append(dict(api_name=api["api_name"],
+                                           api_args=api_args_processed))
         return api_data_processed
 
     @staticmethod
@@ -85,6 +287,8 @@ class PapiExecutor(object):
 
         Apply binascii.unhexlify() method for unicode values.
 
+        TODO: Remove the disabled code when definitely not needed.
+
         :param api_r: API reply.
         :type api_r: dict
         :returns: Processed API reply / a part of API reply.
@@ -112,39 +316,25 @@ class PapiExecutor(object):
         """
 
         if isinstance(api_reply, list):
-            reverted_reply = list()
-            for a_r in api_reply:
-                reverted_reply.append(self._revert_api_reply(a_r))
+            reverted_reply = [self._revert_api_reply(a_r) for a_r in api_reply]
         else:
             reverted_reply = self._revert_api_reply(api_reply)
         return reverted_reply
 
-    def _process_json_data(self):
-        """Process received JSON data."""
-
-        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)
-
-    def execute_papi(self, api_data, timeout=120):
+    def _execute_papi(self, api_data, timeout=120):
         """Execute PAPI command(s) on remote node and store the result.
 
         :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 SSHTimeout: If PAPI command(s) execution has timed out.
         :raises RuntimeError: If PAPI executor failed due to another reason.
         """
-        self._api_data = api_data
+
+        if not api_data:
+            RuntimeError("No API data provided.")
+
         api_data_processed = self._process_api_data(api_data)
         json_data = json.dumps(api_data_processed)
 
@@ -157,68 +347,12 @@ class PapiExecutor(object):
             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']))
+            logger.error("PAPI command(s) execution timeout on host {host}:"
+                         "\n{apis}".format(host=self._node["host"],
+                                           apis=api_data))
             raise
-        except:
-            raise RuntimeError('PAPI command(s) execution on host {host} '
-                               'failed: {apis}'.format(host=self._node['host'],
-                                                       apis=self._api_data))
-
-        self._ret_code = ret_code
-        self._stdout = stdout
-        self._stderr = stderr
-
-    def papi_should_have_failed(self):
-        """Read return code from last executed script and raise exception if the
-        PAPI command(s) didn't fail.
-
-        :raises RuntimeError: When no PAPI command executed.
-        :raises AssertionError: If PAPI command(s) execution passed.
-        """
-
-        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))
-
-    def papi_should_have_passed(self):
-        """Read return code from last executed script and raise exception if the
-        PAPI command(s) failed.
-
-        :raises RuntimeError: When no PAPI command executed.
-        :raises AssertionError: If PAPI command(s) execution failed.
-        """
-
-        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 get_papi_stdout(self):
-        """Returns value of stdout from last executed PAPI command(s)."""
-
-        return self._stdout
-
-    def get_papi_stderr(self):
-        """Returns value of stderr from last executed PAPI command(s)."""
-
-        return self._stderr
-
-    def get_papi_reply(self):
-        """Returns api reply from last executed PAPI command(s)."""
-
-        self._json_data = json.loads(self._stdout)
-        self._process_json_data()
-
-        return self._api_reply
+        except Exception:
+            raise RuntimeError("PAPI command(s) execution on host {host} "
+                               "failed: {apis}".format(host=self._node["host"],
+                                                       apis=api_data))
+        return ret_code, stdout, stderr