|  | #!/usr/bin/env python | 
|  |  | 
|  | r""" | 
|  | This module provides command execution functions such as cmd_fnc and cmd_fnc_u. | 
|  | """ | 
|  |  | 
|  | import os | 
|  | import sys | 
|  | import subprocess | 
|  | import collections | 
|  | import signal | 
|  | import time | 
|  | import re | 
|  | import inspect | 
|  |  | 
|  | import gen_print as gp | 
|  | import gen_valid as gv | 
|  | import gen_misc as gm | 
|  | import func_args as fa | 
|  |  | 
|  | robot_env = gp.robot_env | 
|  |  | 
|  | if robot_env: | 
|  | from robot.libraries.BuiltIn import BuiltIn | 
|  |  | 
|  |  | 
|  | # cmd_fnc and cmd_fnc_u should now be considered deprecated.  shell_cmd and | 
|  | # t_shell_cmd should be used instead. | 
|  | def cmd_fnc(cmd_buf, | 
|  | quiet=None, | 
|  | test_mode=None, | 
|  | debug=0, | 
|  | print_output=1, | 
|  | show_err=1, | 
|  | return_stderr=0, | 
|  | ignore_err=1): | 
|  | r""" | 
|  | Run the given command in a shell and return the shell return code and the | 
|  | output. | 
|  |  | 
|  | Description of arguments: | 
|  | cmd_buf                         The command string to be run in a shell. | 
|  | quiet                           Indicates whether this function should run | 
|  | the print_issuing() function which prints | 
|  | "Issuing: <cmd string>" to stdout. | 
|  | test_mode                       If test_mode is set, this function will | 
|  | not actually run the command.  If | 
|  | print_output is set, it will print | 
|  | "(test_mode) Issuing: <cmd string>" to | 
|  | stdout. | 
|  | debug                           If debug is set, this function will print | 
|  | extra debug info. | 
|  | print_output                    If this is set, this function will print | 
|  | the stdout/stderr generated by the shell | 
|  | command. | 
|  | show_err                        If show_err is set, this function will | 
|  | print a standardized error report if the | 
|  | shell command returns non-zero. | 
|  | return_stderr                   If return_stderr is set, this function | 
|  | will process the stdout and stderr streams | 
|  | from the shell command separately.  It | 
|  | will also return stderr in addition to the | 
|  | return code and the stdout. | 
|  | """ | 
|  |  | 
|  | # Determine default values. | 
|  | quiet = int(gm.global_default(quiet, 0)) | 
|  | test_mode = int(gm.global_default(test_mode, 0)) | 
|  |  | 
|  | if debug: | 
|  | gp.print_vars(cmd_buf, quiet, test_mode, debug) | 
|  |  | 
|  | err_msg = gv.svalid_value(cmd_buf) | 
|  | if err_msg != "": | 
|  | raise ValueError(err_msg) | 
|  |  | 
|  | if not quiet: | 
|  | gp.pissuing(cmd_buf, test_mode) | 
|  |  | 
|  | if test_mode: | 
|  | if return_stderr: | 
|  | return 0, "", "" | 
|  | else: | 
|  | return 0, "" | 
|  |  | 
|  | if return_stderr: | 
|  | err_buf = "" | 
|  | stderr = subprocess.PIPE | 
|  | else: | 
|  | stderr = subprocess.STDOUT | 
|  |  | 
|  | sub_proc = subprocess.Popen(cmd_buf, | 
|  | bufsize=1, | 
|  | shell=True, | 
|  | executable='/bin/bash', | 
|  | stdout=subprocess.PIPE, | 
|  | stderr=stderr) | 
|  | out_buf = "" | 
|  | if return_stderr: | 
|  | for line in sub_proc.stderr: | 
|  | try: | 
|  | err_buf += line | 
|  | except TypeError: | 
|  | line = line.decode("utf-8") | 
|  | err_buf += line | 
|  | if not print_output: | 
|  | continue | 
|  | gp.gp_print(line) | 
|  | for line in sub_proc.stdout: | 
|  | try: | 
|  | out_buf += line | 
|  | except TypeError: | 
|  | line = line.decode("utf-8") | 
|  | out_buf += line | 
|  | if not print_output: | 
|  | continue | 
|  | gp.gp_print(line) | 
|  | if print_output and not robot_env: | 
|  | sys.stdout.flush() | 
|  | sub_proc.communicate() | 
|  | shell_rc = sub_proc.returncode | 
|  | if shell_rc != 0: | 
|  | err_msg = "The prior shell command failed.\n" | 
|  | err_msg += gp.sprint_var(shell_rc, gp.hexa()) | 
|  | if not print_output: | 
|  | err_msg += "out_buf:\n" + out_buf | 
|  |  | 
|  | if show_err: | 
|  | gp.print_error_report(err_msg) | 
|  | if not ignore_err: | 
|  | if robot_env: | 
|  | BuiltIn().fail(err_msg) | 
|  | else: | 
|  | raise ValueError(err_msg) | 
|  |  | 
|  | if return_stderr: | 
|  | return shell_rc, out_buf, err_buf | 
|  | else: | 
|  | return shell_rc, out_buf | 
|  |  | 
|  |  | 
|  | def cmd_fnc_u(cmd_buf, | 
|  | quiet=None, | 
|  | debug=None, | 
|  | print_output=1, | 
|  | show_err=1, | 
|  | return_stderr=0, | 
|  | ignore_err=1): | 
|  | r""" | 
|  | Call cmd_fnc with test_mode=0.  See cmd_fnc (above) for details. | 
|  |  | 
|  | Note the "u" in "cmd_fnc_u" stands for "unconditional". | 
|  | """ | 
|  |  | 
|  | return cmd_fnc(cmd_buf, test_mode=0, quiet=quiet, debug=debug, | 
|  | print_output=print_output, show_err=show_err, | 
|  | return_stderr=return_stderr, ignore_err=ignore_err) | 
|  |  | 
|  |  | 
|  | def parse_command_string(command_string): | 
|  | r""" | 
|  | Parse a bash command-line command string and return the result as a | 
|  | dictionary of parms. | 
|  |  | 
|  | This can be useful for answering questions like "What did the user specify | 
|  | as the value for parm x in the command string?". | 
|  |  | 
|  | This function expects the command string to follow the following posix | 
|  | conventions: | 
|  | - Short parameters: | 
|  | -<parm name><space><arg value> | 
|  | - Long parameters: | 
|  | --<parm name>=<arg value> | 
|  |  | 
|  | The first item in the string will be considered to be the command.  All | 
|  | values not conforming to the specifications above will be considered | 
|  | positional parms.  If there are multiple parms with the same name, they | 
|  | will be put into a list (see illustration below where "-v" is specified | 
|  | multiple times). | 
|  |  | 
|  | Description of argument(s): | 
|  | command_string                  The complete command string including all | 
|  | parameters and arguments. | 
|  |  | 
|  | Sample input: | 
|  |  | 
|  | robot_cmd_buf:                                    robot -v | 
|  | OPENBMC_HOST:dummy1 -v keyword_string:'Set Auto Reboot  no' -v | 
|  | lib_file_path:/home/user1/git/openbmc-test-automation/lib/utils.robot -v | 
|  | quiet:0 -v test_mode:0 -v debug:0 | 
|  | --outputdir='/home/user1/status/children/' | 
|  | --output=dummy1.Auto_reboot.170802.124544.output.xml | 
|  | --log=dummy1.Auto_reboot.170802.124544.log.html | 
|  | --report=dummy1.Auto_reboot.170802.124544.report.html | 
|  | /home/user1/git/openbmc-test-automation/extended/run_keyword.robot | 
|  |  | 
|  | Sample output: | 
|  |  | 
|  | robot_cmd_buf_dict: | 
|  | robot_cmd_buf_dict[command]:                    robot | 
|  | robot_cmd_buf_dict[v]: | 
|  | robot_cmd_buf_dict[v][0]:                     OPENBMC_HOST:dummy1 | 
|  | robot_cmd_buf_dict[v][1]:                     keyword_string:Set Auto | 
|  | Reboot no | 
|  | robot_cmd_buf_dict[v][2]: | 
|  | lib_file_path:/home/user1/git/openbmc-test-automation/lib/utils.robot | 
|  | robot_cmd_buf_dict[v][3]:                     quiet:0 | 
|  | robot_cmd_buf_dict[v][4]:                     test_mode:0 | 
|  | robot_cmd_buf_dict[v][5]:                     debug:0 | 
|  | robot_cmd_buf_dict[outputdir]: | 
|  | /home/user1/status/children/ | 
|  | robot_cmd_buf_dict[output]: | 
|  | dummy1.Auto_reboot.170802.124544.output.xml | 
|  | robot_cmd_buf_dict[log]: | 
|  | dummy1.Auto_reboot.170802.124544.log.html | 
|  | robot_cmd_buf_dict[report]: | 
|  | dummy1.Auto_reboot.170802.124544.report.html | 
|  | robot_cmd_buf_dict[positional]: | 
|  | /home/user1/git/openbmc-test-automation/extended/run_keyword.robot | 
|  | """ | 
|  |  | 
|  | # We want the parms in the string broken down the way bash would do it, | 
|  | # so we'll call upon bash to do that by creating a simple inline bash | 
|  | # function. | 
|  | bash_func_def = "function parse { for parm in \"${@}\" ; do" +\ | 
|  | " echo $parm ; done ; }" | 
|  |  | 
|  | rc, outbuf = cmd_fnc_u(bash_func_def + " ; parse " + command_string, | 
|  | quiet=1, print_output=0) | 
|  | command_string_list = outbuf.rstrip("\n").split("\n") | 
|  |  | 
|  | command_string_dict = collections.OrderedDict() | 
|  | ix = 1 | 
|  | command_string_dict['command'] = command_string_list[0] | 
|  | while ix < len(command_string_list): | 
|  | if command_string_list[ix].startswith("--"): | 
|  | key, value = command_string_list[ix].split("=") | 
|  | key = key.lstrip("-") | 
|  | elif command_string_list[ix].startswith("-"): | 
|  | key = command_string_list[ix].lstrip("-") | 
|  | ix += 1 | 
|  | try: | 
|  | value = command_string_list[ix] | 
|  | except IndexError: | 
|  | value = "" | 
|  | else: | 
|  | key = 'positional' | 
|  | value = command_string_list[ix] | 
|  | if key in command_string_dict: | 
|  | if isinstance(command_string_dict[key], str): | 
|  | command_string_dict[key] = [command_string_dict[key]] | 
|  | command_string_dict[key].append(value) | 
|  | else: | 
|  | command_string_dict[key] = value | 
|  | ix += 1 | 
|  |  | 
|  | return command_string_dict | 
|  |  | 
|  |  | 
|  | # Save the original SIGALRM handler for later restoration by shell_cmd. | 
|  | original_sigalrm_handler = signal.getsignal(signal.SIGALRM) | 
|  |  | 
|  |  | 
|  | def shell_cmd_timed_out(signal_number, | 
|  | frame): | 
|  | r""" | 
|  | Handle an alarm signal generated during the shell_cmd function. | 
|  | """ | 
|  |  | 
|  | gp.dprint_executing() | 
|  | # Get subprocess pid from shell_cmd's call stack. | 
|  | sub_proc = gp.get_stack_var('sub_proc', 0) | 
|  | pid = sub_proc.pid | 
|  | # Terminate the child process. | 
|  | os.kill(pid, signal.SIGTERM) | 
|  | # Restore the original SIGALRM handler. | 
|  | signal.signal(signal.SIGALRM, original_sigalrm_handler) | 
|  |  | 
|  | return | 
|  |  | 
|  |  | 
|  | def shell_cmd(command_string, | 
|  | quiet=None, | 
|  | print_output=None, | 
|  | show_err=1, | 
|  | test_mode=0, | 
|  | time_out=None, | 
|  | max_attempts=1, | 
|  | retry_sleep_time=5, | 
|  | allowed_shell_rcs=[0], | 
|  | ignore_err=None, | 
|  | return_stderr=0, | 
|  | fork=0): | 
|  | r""" | 
|  | Run the given command string in a shell and return a tuple consisting of | 
|  | the shell return code and the output. | 
|  |  | 
|  | Description of argument(s): | 
|  | command_string                  The command string to be run in a shell | 
|  | (e.g. "ls /tmp"). | 
|  | quiet                           If set to 0, this function will print | 
|  | "Issuing: <cmd string>" to stdout.  When | 
|  | the quiet argument is set to None, this | 
|  | function will assign a default value by | 
|  | searching upward in the stack for the | 
|  | quiet variable value.  If no such value is | 
|  | found, quiet is set to 0. | 
|  | print_output                    If this is set, this function will print | 
|  | the stdout/stderr generated by the shell | 
|  | command to stdout. | 
|  | show_err                        If show_err is set, this function will | 
|  | print a standardized error report if the | 
|  | shell command fails (i.e. if the shell | 
|  | command returns a shell_rc that is not in | 
|  | allowed_shell_rcs).  Note: Error text is | 
|  | only printed if ALL attempts to run the | 
|  | command_string fail.  In other words, if | 
|  | the command execution is ultimately | 
|  | successful, initial failures are hidden. | 
|  | test_mode                       If test_mode is set, this function will | 
|  | not actually run the command.  If | 
|  | print_output is also set, this function | 
|  | will print "(test_mode) Issuing: <cmd | 
|  | string>" to stdout.  A caller should call | 
|  | shell_cmd directly if they wish to have | 
|  | the command string run unconditionally. | 
|  | They should call the t_shell_cmd wrapper | 
|  | (defined below) if they wish to run the | 
|  | command string only if the prevailing | 
|  | test_mode variable is set to 0. | 
|  | time_out                        A time-out value expressed in seconds.  If | 
|  | the command string has not finished | 
|  | executing within <time_out> seconds, it | 
|  | will be halted and counted as an error. | 
|  | max_attempts                    The max number of attempts that should be | 
|  | made to run the command string. | 
|  | retry_sleep_time                The number of seconds to sleep between | 
|  | attempts. | 
|  | allowed_shell_rcs               A list of integers indicating which | 
|  | shell_rc values are not to be considered | 
|  | errors. | 
|  | ignore_err                      Ignore error means that a failure | 
|  | encountered by running the command string | 
|  | will not be raised as a python exception. | 
|  | When the ignore_err argument is set to | 
|  | None, this function will assign a default | 
|  | value by searching upward in the stack for | 
|  | the ignore_err variable value.  If no such | 
|  | value is found, ignore_err is set to 1. | 
|  | return_stderr                   If return_stderr is set, this function | 
|  | will process the stdout and stderr streams | 
|  | from the shell command separately.  In | 
|  | such a case, the tuple returned by this | 
|  | function will consist of three values | 
|  | rather than just two: rc, stdout, stderr. | 
|  | fork                            Run the command string asynchronously | 
|  | (i.e. don't wait for status of the child | 
|  | process and don't try to get | 
|  | stdout/stderr). | 
|  | """ | 
|  |  | 
|  | # Assign default values to some of the arguments to this function. | 
|  | quiet = int(gm.dft(quiet, gp.get_stack_var('quiet', 0))) | 
|  | print_output = int(gm.dft(print_output, not quiet)) | 
|  | show_err = int(show_err) | 
|  | global_ignore_err = gp.get_var_value(ignore_err, 1) | 
|  | stack_ignore_err = gp.get_stack_var('ignore_err', global_ignore_err) | 
|  | ignore_err = int(gm.dft(ignore_err, gm.dft(stack_ignore_err, 1))) | 
|  |  | 
|  | err_msg = gv.svalid_value(command_string) | 
|  | if err_msg != "": | 
|  | raise ValueError(err_msg) | 
|  |  | 
|  | if not quiet: | 
|  | gp.print_issuing(command_string, test_mode) | 
|  |  | 
|  | if test_mode: | 
|  | if return_stderr: | 
|  | return 0, "", "" | 
|  | else: | 
|  | return 0, "" | 
|  |  | 
|  | # Convert each list entry to a signed value. | 
|  | allowed_shell_rcs = fa.source_to_object(allowed_shell_rcs) | 
|  | allowed_shell_rcs = [gm.to_signed(x) for x in allowed_shell_rcs] | 
|  |  | 
|  | if return_stderr: | 
|  | stderr = subprocess.PIPE | 
|  | else: | 
|  | stderr = subprocess.STDOUT | 
|  |  | 
|  | shell_rc = 0 | 
|  | out_buf = "" | 
|  | err_buf = "" | 
|  | # Write all output to func_history_stdout rather than directly to stdout. | 
|  | # This allows us to decide what to print after all attempts to run the | 
|  | # command string have been made.  func_history_stdout will contain the | 
|  | # complete stdout history from the current invocation of this function. | 
|  | func_history_stdout = "" | 
|  | for attempt_num in range(1, max_attempts + 1): | 
|  | sub_proc = subprocess.Popen(command_string, | 
|  | bufsize=1, | 
|  | shell=True, | 
|  | executable='/bin/bash', | 
|  | stdout=subprocess.PIPE, | 
|  | stderr=stderr) | 
|  | out_buf = "" | 
|  | err_buf = "" | 
|  | # Output from this loop iteration is written to func_stdout for later | 
|  | # processing. | 
|  | func_stdout = "" | 
|  | if fork: | 
|  | break | 
|  | command_timed_out = False | 
|  | if time_out is not None: | 
|  | # Designate a SIGALRM handling function and set alarm. | 
|  | signal.signal(signal.SIGALRM, shell_cmd_timed_out) | 
|  | signal.alarm(time_out) | 
|  | try: | 
|  | if return_stderr: | 
|  | for line in sub_proc.stderr: | 
|  | try: | 
|  | err_buf += line | 
|  | except TypeError: | 
|  | line = line.decode("utf-8") | 
|  | err_buf += line | 
|  | if not print_output: | 
|  | continue | 
|  | func_stdout += line | 
|  | for line in sub_proc.stdout: | 
|  | try: | 
|  | out_buf += line | 
|  | except TypeError: | 
|  | line = line.decode("utf-8") | 
|  | out_buf += line | 
|  | if not print_output: | 
|  | continue | 
|  | func_stdout += line | 
|  | except IOError: | 
|  | command_timed_out = True | 
|  | sub_proc.communicate() | 
|  | shell_rc = sub_proc.returncode | 
|  | # Restore the original SIGALRM handler and clear the alarm. | 
|  | signal.signal(signal.SIGALRM, original_sigalrm_handler) | 
|  | signal.alarm(0) | 
|  | if shell_rc in allowed_shell_rcs: | 
|  | break | 
|  | err_msg = "The prior shell command failed.\n" | 
|  | if quiet: | 
|  | err_msg += gp.sprint_var(command_string) | 
|  | if command_timed_out: | 
|  | err_msg += gp.sprint_var(command_timed_out) | 
|  | err_msg += gp.sprint_var(time_out) | 
|  | err_msg += gp.sprint_varx("child_pid", sub_proc.pid) | 
|  | err_msg += gp.sprint_var(attempt_num) | 
|  | err_msg += gp.sprint_var(shell_rc, gp.hexa()) | 
|  | err_msg += gp.sprint_var(allowed_shell_rcs, gp.hexa()) | 
|  | if not print_output: | 
|  | if return_stderr: | 
|  | err_msg += "err_buf:\n" + err_buf | 
|  | err_msg += "out_buf:\n" + out_buf | 
|  | if show_err: | 
|  | func_stdout += gp.sprint_error_report(err_msg) | 
|  | func_history_stdout += func_stdout | 
|  | if attempt_num < max_attempts: | 
|  | func_history_stdout += gp.sprint_issuing("time.sleep(" | 
|  | + str(retry_sleep_time) | 
|  | + ")") | 
|  | time.sleep(retry_sleep_time) | 
|  |  | 
|  | if shell_rc not in allowed_shell_rcs: | 
|  | func_stdout = func_history_stdout | 
|  |  | 
|  | gp.gp_print(func_stdout) | 
|  |  | 
|  | if shell_rc not in allowed_shell_rcs: | 
|  | if not ignore_err: | 
|  | if robot_env: | 
|  | BuiltIn().fail(err_msg) | 
|  | else: | 
|  | raise ValueError("The prior shell command failed.\n") | 
|  |  | 
|  | if return_stderr: | 
|  | return shell_rc, out_buf, err_buf | 
|  | else: | 
|  | return shell_rc, out_buf | 
|  |  | 
|  |  | 
|  | def t_shell_cmd(command_string, **kwargs): | 
|  | r""" | 
|  | Search upward in the the call stack to obtain the test_mode argument, add | 
|  | it to kwargs and then call shell_cmd and return the result. | 
|  |  | 
|  | See shell_cmd prolog for details on all arguments. | 
|  | """ | 
|  |  | 
|  | if 'test_mode' in kwargs: | 
|  | error_message = "Programmer error - test_mode is not a valid" +\ | 
|  | " argument to this function." | 
|  | gp.print_error_report(error_message) | 
|  | exit(1) | 
|  |  | 
|  | test_mode = gp.get_stack_var('test_mode', | 
|  | int(gp.get_var_value(None, 0, "test_mode"))) | 
|  | kwargs['test_mode'] = test_mode | 
|  |  | 
|  | return shell_cmd(command_string, **kwargs) | 
|  |  | 
|  |  | 
|  | def re_order_kwargs(stack_frame_ix, **kwargs): | 
|  | r""" | 
|  | Re-order the kwargs to match the order in which they were specified on a | 
|  | function invocation and return as an ordered dictionary. | 
|  |  | 
|  | Note that this re_order_kwargs function should not be necessary in python | 
|  | versions 3.6 and beyond. | 
|  |  | 
|  | Example: | 
|  |  | 
|  | The caller calls func1 like this: | 
|  |  | 
|  | func1('mike', arg1='one', arg2='two', arg3='three') | 
|  |  | 
|  | And func1 is defined as follows: | 
|  |  | 
|  | def func1(first_arg, **kwargs): | 
|  |  | 
|  | kwargs = re_order_kwargs(first_arg_num=2, stack_frame_ix=3, **kwargs) | 
|  |  | 
|  | The kwargs dictionary before calling re_order_kwargs (where order is not | 
|  | guaranteed): | 
|  |  | 
|  | kwargs: | 
|  | kwargs[arg3]:          three | 
|  | kwargs[arg2]:          two | 
|  | kwargs[arg1]:          one | 
|  |  | 
|  | The kwargs dictionary after calling re_order_kwargs: | 
|  |  | 
|  | kwargs: | 
|  | kwargs[arg1]:          one | 
|  | kwargs[arg2]:          two | 
|  | kwargs[arg3]:          three | 
|  |  | 
|  | Note that the re-ordered kwargs match the order specified on the call to | 
|  | func1. | 
|  |  | 
|  | Description of argument(s): | 
|  | stack_frame_ix                  The stack frame of the function whose | 
|  | kwargs values must be re-ordered.  0 is | 
|  | the stack frame of re_order_kwargs, 1 is | 
|  | the stack from of its caller and so on. | 
|  | kwargs                          The keyword argument dictionary which is | 
|  | to be re-ordered. | 
|  | """ | 
|  |  | 
|  | new_kwargs = collections.OrderedDict() | 
|  |  | 
|  | # Get position number of first keyword on the calling line of code. | 
|  | (args, varargs, keywords, locals) =\ | 
|  | inspect.getargvalues(inspect.stack()[stack_frame_ix][0]) | 
|  | first_kwarg_pos = 1 + len(args) | 
|  | if varargs is not None: | 
|  | first_kwarg_pos += len(locals[varargs]) | 
|  | for arg_num in range(first_kwarg_pos, first_kwarg_pos + len(kwargs)): | 
|  | # This will result in an arg_name value such as "arg1='one'". | 
|  | arg_name = gp.get_arg_name(None, arg_num, stack_frame_ix + 2) | 
|  | # Continuing with the prior example, the following line will result | 
|  | # in key being set to 'arg1'. | 
|  | key = arg_name.split('=')[0] | 
|  | new_kwargs[key] = kwargs[key] | 
|  |  | 
|  | return new_kwargs | 
|  |  | 
|  |  | 
|  | def default_arg_delim(arg_dashes): | 
|  | r""" | 
|  | Return the default argument delimiter value for the given arg_dashes value. | 
|  |  | 
|  | Note: this function is useful for functions that manipulate bash command | 
|  | line arguments (e.g. --parm=1 or -parm 1). | 
|  |  | 
|  | Description of argument(s): | 
|  | arg_dashes                      The argument dashes specifier (usually, | 
|  | "-" or "--"). | 
|  | """ | 
|  |  | 
|  | if arg_dashes == "--": | 
|  | return "=" | 
|  |  | 
|  | return " " | 
|  |  | 
|  |  | 
|  | def create_command_string(command, *pos_parms, **options): | 
|  | r""" | 
|  | Create and return a bash command string consisting of the given arguments | 
|  | formatted as text. | 
|  |  | 
|  | The default formatting of options is as follows: | 
|  |  | 
|  | <single dash><option name><space delim><option value> | 
|  |  | 
|  | Example: | 
|  |  | 
|  | -parm value | 
|  |  | 
|  | The caller can change the kind of dashes/delimiters used by specifying | 
|  | "arg_dashes" and/or "arg_delims" as options.  These options are processed | 
|  | specially by the create_command_string function and do NOT get inserted | 
|  | into the resulting command string.  All options following the | 
|  | arg_dashes/arg_delims options will then use the specified values for | 
|  | dashes/delims.  In the special case of arg_dashes equal to "--", the | 
|  | arg_delim will automatically be changed to "=".  See examples below. | 
|  |  | 
|  | Quoting rules: | 
|  |  | 
|  | The create_command_string function will single quote option values as | 
|  | needed to prevent bash expansion.  If the caller wishes to defeat this | 
|  | action, they may single or double quote the option value themselves.  See | 
|  | examples below. | 
|  |  | 
|  | pos_parms are NOT automatically quoted.  The caller is advised to either | 
|  | explicitly add quotes or to use the quote_bash_parm functions to quote any | 
|  | pos_parms. | 
|  |  | 
|  | Examples: | 
|  |  | 
|  | command_string = create_command_string('cd', '~') | 
|  |  | 
|  | Result: | 
|  | cd ~ | 
|  |  | 
|  | Note that the pos_parm ("~") does NOT get quoted, as per the | 
|  | aforementioned rules.  If quotes are desired, they may be added explicitly | 
|  | by the caller: | 
|  |  | 
|  | command_string = create_command_string('cd', '\'~\'') | 
|  |  | 
|  | Result: | 
|  | cd '~' | 
|  |  | 
|  | command_string = create_command_string('grep', '\'^[^ ]*=\'', | 
|  | '/tmp/myfile', i=None, m='1', arg_dashes='--', color='always') | 
|  |  | 
|  | Result: | 
|  | grep -i -m 1 --color=always '^[^ ]*=' /tmp/myfile | 
|  |  | 
|  | In the preceding example, note the use of None to cause the "i" parm to be | 
|  | treated as a flag (i.e. no argument value is generated).  Also, note the | 
|  | use of arg_dashes to change the type of dashes used on all subsequent | 
|  | options.  The following example is equivalent to the prior.  Note that | 
|  | quote_bash_parm is used instead of including the quotes explicitly. | 
|  |  | 
|  | command_string = create_command_string('grep', quote_bash_parm('^[^ ]*='), | 
|  | '/tmp/myfile', i=None,  m='1', arg_dashes='--', color='always') | 
|  |  | 
|  | Result: | 
|  | grep -i -m 1 --color=always '^[^ ]*=' /tmp/myfile | 
|  |  | 
|  | In the following example, note the automatic quoting of the password | 
|  | option, as per the aforementioned rules. | 
|  |  | 
|  | command_string = create_command_string('my_pgm', '/tmp/myfile', i=None, | 
|  | m='1', arg_dashes='--', password='${my_pw}') | 
|  |  | 
|  | However, let's say that the caller wishes to have bash expand the password | 
|  | value.  To achieve this, the caller can use double quotes: | 
|  |  | 
|  | command_string = create_command_string('my_pgm', '/tmp/myfile', i=None, | 
|  | m='1', arg_dashes='--', password='"${my_pw}"') | 
|  |  | 
|  | Result: | 
|  | my_pgm -i -m 1 --password="${my_pw}" /tmp/myfile | 
|  |  | 
|  | command_string = create_command_string('ipmitool', 'power status', | 
|  | I='lanplus', C='3', U='root', P='0penBmc', H='wsbmc010') | 
|  |  | 
|  | Result: | 
|  | ipmitool -I lanplus -C 3 -U root -P 0penBmc -H wsbmc010 power status | 
|  |  | 
|  | By default create_command_string will take measures to preserve the order | 
|  | of the callers options.  In some cases, this effort may fail (as when | 
|  | calling directly from a robot program).  In this case, the caller can | 
|  | accept the responsibility of keeping an ordered list of options by calling | 
|  | this function with the last positional parm as some kind of dictionary | 
|  | (preferably an OrderedDict) and avoiding the use of any actual option args. | 
|  |  | 
|  | Example: | 
|  | kwargs = collections.OrderedDict([('pass', 0), ('fail', 0)]) | 
|  | command_string = create_command_string('my program', 'pos_parm1', kwargs) | 
|  |  | 
|  | Result: | 
|  |  | 
|  | my program -pass 0 -fail 0 pos_parm1 | 
|  |  | 
|  | Note to programmers who wish to write a wrapper to this function:  To get | 
|  | the options to be processed correctly, the wrapper function must include a | 
|  | _stack_frame_ix_ keyword argument to allow this function to properly | 
|  | re-order options: | 
|  |  | 
|  | def create_ipmi_ext_command_string(command, **kwargs): | 
|  |  | 
|  | return create_command_string('ipmitool', command, _stack_frame_ix_=2, | 
|  | **kwargs) | 
|  |  | 
|  | Example call of wrapper function: | 
|  |  | 
|  | command_string = create_ipmi_ext_command_string('power status', | 
|  | I='lanplus') | 
|  |  | 
|  | Description of argument(s): | 
|  | command                         The command (e.g. "cat", "sort", | 
|  | "ipmitool", etc.). | 
|  | pos_parms                       The positional parms for the command (e.g. | 
|  | PATTERN, FILENAME, etc.).  These will be | 
|  | placed at the end of the resulting command | 
|  | string. | 
|  | options                         The command options (e.g. "-m 1", | 
|  | "--max-count=NUM", etc.).  Note that if | 
|  | the value of any option is None, then it | 
|  | will be understood to be a flag (for which | 
|  | no value is required). | 
|  | """ | 
|  |  | 
|  | arg_dashes = "-" | 
|  | delim = default_arg_delim(arg_dashes) | 
|  |  | 
|  | command_string = command | 
|  |  | 
|  | if len(pos_parms) > 0 and gp.is_dict(pos_parms[-1]): | 
|  | # Convert pos_parms from tuple to list. | 
|  | pos_parms = list(pos_parms) | 
|  | # Re-assign options to be the last pos_parm value (which is a | 
|  | # dictionary). | 
|  | options = pos_parms[-1] | 
|  | # Now delete the last pos_parm. | 
|  | del pos_parms[-1] | 
|  | else: | 
|  | # Either get stack_frame_ix from the caller via options or set it to | 
|  | # the default value. | 
|  | if '_stack_frame_ix_' in options: | 
|  | stack_frame_ix = options['_stack_frame_ix_'] | 
|  | del options['_stack_frame_ix_'] | 
|  | else: | 
|  | stack_frame_ix = 1 | 
|  | # Re-establish the original options order as specified on the | 
|  | # original line of code.  This function depends on correct order. | 
|  | options = re_order_kwargs(stack_frame_ix, **options) | 
|  | for key, value in options.items(): | 
|  | # Check for special values in options and process them. | 
|  | if key == "arg_dashes": | 
|  | arg_dashes = str(value) | 
|  | delim = default_arg_delim(arg_dashes) | 
|  | continue | 
|  | if key == "arg_delim": | 
|  | delim = str(value) | 
|  | continue | 
|  | # Format the options elements into the command string. | 
|  | command_string += " " + arg_dashes + key | 
|  | if value is not None: | 
|  | command_string += delim | 
|  | if re.match(r'^(["].*["]|[\'].*[\'])$', str(value)): | 
|  | # Already quoted. | 
|  | command_string += str(value) | 
|  | else: | 
|  | command_string += gm.quote_bash_parm(str(value)) | 
|  | # Finally, append the pos_parms to the end of the command_string.  Use | 
|  | # filter to eliminate blank pos parms. | 
|  | command_string = ' '.join([command_string] + list(filter(None, pos_parms))) | 
|  |  | 
|  | return command_string |