命令行帮助信息、手动和交互执行
一、方式一
1、先定义一个命令行解析类
class CommandLineParser:
def __init__(self):
self.arguments = {}
self.valid_options = {
"help", "mode", "interval", "export", "wave_data_export", "wave_set",
"ip", "serial_path", "rate", "devid", "url", "topic", "user", "passw",
}
def parse(self, args):
current_name = ""
values = []
invalid_options = []
for arg in args:
if arg.startswith("--"):
if current_name != "" and values:
self.arguments[current_name] = values
values = []
current_name = arg[2:]
elif arg.startswith("-"):
if current_name != "" and values:
self.arguments[current_name] = values
values = []
current_name = arg[1:]
else:
values.append(arg)
if current_name != "":
self.arguments[current_name] = values
for key in self.arguments.keys():
if key not in self.valid_options:
invalid_options.append(key)
if invalid_options:
raise ValueError(f"Invalid option(s): {' '.join(invalid_options)}")
def contains(self, name):
return name in self.arguments
def get_help_message(self):
script_name = sys.argv[0]
return f"""
Usage: python {script_name} [options]
Options:
--help Show this help message and exit
--mode Choose connection mode (1 for MIB RS232, 2 for LAN)
--interval Data Transmission interval (1-5)
--export Data export option (1-4)
--wave_set Waveform data export priority option (0-12)
--wave_data_export Choose Waveform data export scale option (1-2)
--ip Target IP address for LAN
--serial_path Target Serial port path for MIB
--rate Serial baudrate for MIB
--devid Device ID/Name for export
--url Data export URL (JSON or MQTT WebSocket)
--topic MQTT Topic
--user MQTT Username
--passw MQTT Password
Examples:
python {script_name} --mode 1 --interval 1 --export 1 --wave_set 0 --wave_data_export 1 --serial_path /dev/ttyS5 --rate 115200
python {script_name} --mode 2 --interval 1 --export 1 --wave_set 0 --wave_data_export 1 --ip localhost
"""
2、定义一个获取交互的函数，命令参数没有就从交互中取
def get_input(parser, key, options=None, prompt="", default=None):
if options is None:
options = []
if parser.arguments.get(key):
return parser.arguments[key][0]
else:
if default is not None:
return default
if options:
for option in options:
print(option)
return input(prompt)
3、使用get_input取值
ip_address_remote = get_input(parser, 'ip', prompt="Enter the target IP address of the monitor assigned by DHCP: ",
default="localhost")
4、程序入口
def main(args):
parser = CommandLineParser()
try:
parser.parse(args)
if parser.contains('help'):
print(parser.get_help_message())
return
except ValueError as e:
print(e)
print(parser.get_help_message())
return
ser_connect_set = get_input(parser, 'mode', ["1. Connect via MIB RS232 port", "2. Connect via LAN port"],
"Choose connection mode (1-2): ", default='2')
if ser_connect_set == "1":
connect_via_MIB(args)
elif ser_connect_set == "2":
connect_via_lan(args)
else:
print("Invalid mode selected!")
if __name__ == '__main__':
main(sys.argv[1:])
二、方式二（getopt）
1、定义一个解析函数
def print_help():
print("python {} ".format(__file__))
print("python {} --serial-path=/dev/ttyS0 --serial-rate=115200"
.format(__file__))
print("python {} --serial-path=COM3 --serial-rate=115200"
.format(__file__))
def parse_args(argv):
try:
options, args = getopt.getopt(argv, "h", ["help", "serial-path=", "serial-rate="])
except getopt.GetoptError:
sys.exit()
serial_path, serial_rate = "/dev/ttyS0", 115200
for option, value in options: # [('--serial-path', 'COM5')]
if option in ("-h", "--help"):
print_help()
sys.exit()
if option in "--serial-path":
serial_path = value
if option in "--serial-rate":
serial_rate = int(value)
return serial_path, serial_rate
2、程序入库
if __name__ == '__main__':
serial_path, serial_rate = parse_args(sys.argv[1:])
if not check_serial_port(serial_path):
sys.exit(-1)
simulator = PhilipsMpMPMonitorSimulator(serial_path, serial_rate)
signal.signal(signal.SIGINT, signal_handler)
3、关于getopt模块的介绍
导入模块
import getopt import sys
基本语法
getopt.getopt(args, shortopts, longopts=[])
参数说明：
args: 通常是 sys.argv[1:]，即命令行参数列表（不包括脚本名）
shortopts: 短选项字符串，每个字符代表一个选项
longopts: 长选项列表
使用示例
import getopt
import sys
def main():
try:
opts, args = getopt.getopt(sys.argv[1:], "ho:vf:dm:", [
"help", "output=", "file=", "debug", "mode=", "name=", "version"
])
except getopt.GetoptError as err:
print(str(err))
usage()
sys.exit(2)
output = None
verbose = False
input_file = None
debug = False
mode = "default"
name = None
for o, a in opts:
if o in ("-h", "--help"):
usage()
sys.exit()
elif o in ("-o", "--output"):
output = a
print(output)
elif o == "-v":
verbose = True
print(verbose)
elif o in ("-f", "--file"):
input_file = a
print(input_file)
elif o in ("-d", "--debug"):
debug = True
print(debug)
elif o in ("-m", "--mode"):
mode = a
print(mode)
elif o == "--name":
name = a
print(name)
elif o == "--version":
print("Script Version 1.0")
sys.exit()
else:
assert False, "unhandled option"
def usage():
print("""Usage: script.py [OPTIONS]
Options:
-h, --help Show this help message and exit
-o OUTPUT, --output=OUTPUT
Specify output file
-v Verbose mode
-f FILE, --file=FILE Input file
-d, --debug Enable debug mode
-m MODE, --mode=MODE Specify operation mode
--name=NAME Specify name
--version Show version information
""")
if __name__ == "__main__":
main()
关键点：
短选项格式：单个字母后跟冒号表示该选项需要参数，如 "ho:vf:dm:"
h: 不需要参数o:: 需要参数v: 不需要参数f:: 需要参数d: 不需要参数m:: 需要参数- name这里没有短选项
长选项格式：选项名后跟等号表示需要参数，如 ["help", "output="]
getopt() 返回两个值：(options, args)
options 是一个 (option, value) 对的列表，列表套元组
args 包含那些没有被 opts 处理的命令行参数
错误处理：
使用 try-except 块来捕获 getopt.GetoptError 异常，这样可以处理无效的命令行参数。
三、最推荐使用的argparse和click
1、argparse：
是Python标准库中最推荐使用的命令行解析模块。它功能强大，使用简单，并能自动生成帮助和使用信息。
import argparse
parser = argparse.ArgumentParser(description='Description of your program')
parser.add_argument('-o', '--output', help='Output file')
parser.add_argument('-v', '--verbose', action='store_true', help='Verbose mode')
args = parser.parse_args()
if args.verbose:
print("Verbose mode enabled")
2、click：
这是一个第三方库，设计得非常优雅和直观。它使用装饰器来定义命令行接口，非常适合构建复杂的命令行应用。
import click
@click.command()
@click.option('--count', default=1, help='Number of greetings.')
@click.option('--name', prompt='Your name', help='The person to greet.')
def hello(count, name):
for _ in range(count):
click.echo(f"Hello, {name}!")
if __name__ == '__main__':
hello()