python中自带了一些命令行工具，可以用来快速处理一些工作。我把这些命令行工具称之为 冷兵器 ，没有趁手的工具时候可以顶替使用。这些工具都是python标准模块，具有 main 函数，直接使用 python -m 命令执行，多数可以使用 -h/--help查看帮助。
本文以python3版本为准
1. http 服务
启动一个http的静态文件服务
# python -m http.serve r Serving HTTP on :: port 8000 (http://[::]:8000/) ...
2. json 格式化
格式化json数据
# echo '{"amount":3.4}' | python -m json.tool { "amount": 3.4 }
3. 可视化编辑器和shell
idlelib模块基于tkinter，可以作为编辑器和shell使用。文件编辑器效果。
python -m idlelib myapp/example.py
shell效果
python -m idlelib
4. python 应用程序打包
构建myapp目录如下:
├── myapp │ ├── example.py │ └── hello.py 复制代码
代码分别如下:
# example.py import hello def main(): print('Hello World') hello.say_hello("python") if __name__=='__main__': main() # hello.py def say_hello(name): print("hello",name)
将整个myapp打包成应用程序，命令执行后会生成一个名叫 myapp.pyz 应用程序。
python -m zipapp myapp -m "example:main"
使用python直接运行应用程序
# python myapp.pyz Hello World hello python
5. ROT13 加密
rot13（rotate by 13 places）是一种简易的替换式密码，是凯撒密码的变种。rot13将原文偏移13位形成密文，因为英文总共26位，所以密文再偏移13位后会回到原文。公式: rot13(rot13(xxx))=xxx。
# echo "xxx" | python -m encodings.rot_13 Tvir zr n fgne
作为一个小彩蛋，欢迎大家动手破译一下xxx的值
6. base64 编码
对一个字符串进行base64编码
# echo "haha" | python -m base64 aGFoYQo= # echo "aGFoYQo=" | python -m base64 -d haha
base64还支持对文件编码。编写测试代码
# sample.py def main(): print('Hello World👌') if __name__=='__main__': main()
将代码编译成base64字符串
# python -m base64 sample.py CmRlZiBtYWluKCk6CiAgIHByaW50KCdIZWxsbyBXb3JsZPCfkYwnKQogICAKaWYgX19uYW1lX189 PSdfX21haW5fXyc6CiAgIG1haW4oKQo=
执行编译后的代码
# echo "CmRlZiBtYWluKCk6CiAgIHByaW50KCdIZWxsbyBXb3JsZPCfkYwnKQogICAKaWYgX19uYW1lX189 PSdfX21haW5fXyc6CiAgIG1haW4oKQo=" | python -m base64 -d | python Hello World👌
类似的可以使用uu(Unix-to-Unix encoding)编码代码:
# python -m uu sample.py begin 644 sample.py M"F1E9B!M86EN*"DZ"B @('!R:6YT*"=(96QL;R!7;W)L9/"?D8PG*0H@(" * C:68@7U]N86UE7U\]/2=?7VUA:6Y?7R<Z"B @(&UA:6XH*0H end
使用quopri(Encode and decode MIME quoted-printable data)编码代码:
# python -m quopri -t sample.py def=20main(): =20=20=20print('Hello=20World=F0=9F=91=8C') =20=20=20 if=20__name__=3D=3D'__main__': =20=20=20main()
7. mime 识别
识别文件或者url的mime类型
# python -m mimetypes https://docs.python.org/3/library/mimetypes.html type: text/html encoding: None # html # python -m mimetypes https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png type: image/png encoding: None # png # python -m mimetypes sample.py type: text/x-python encoding: None # python文件 # python -m mimetypes sample.py.gz type: text/x-python encoding: gzip # python文件，gzip压缩
8. 查看python环境信息
python -m sysconfig Platform: "macosx-10.9-x86_64" Python version: "3.8" Current installation scheme: "posix_prefix" Paths: data = "/Users/yoo/work/yuanmahui/python/.venv" include = "/Library/Frameworks/Python.framework/Versions/3.8/include/python3.8" ... Variables: ... PYTHON = "python" PYTHONFRAMEWORK = "Python" PYTHONFRAMEWORKDIR = "Python.framework" PYTHONFRAMEWORKINSTALLDIR = "/Library/Frameworks/Python.framework" ...
也可以使用下面命令查看系统路径
# python -m site sys.path = [ '/Users/yoo/work/yuanmahui/python/python-tools', '/Library/Frameworks/Python.framework/Versions/3.8/lib/python38.zip', '/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8', '/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/lib-dynload', '/Users/yoo/work/yuanmahui/python/.venv/lib/python3.8/site-packages', ] USER_BASE: '/Users/yoo/Library/Python/3.8' (exists) USER_SITE: '/Users/yoo/Library/Python/3.8/lib/python/site-packages' (exists) ENABLE_USER_SITE: False
9. 编译脚本
compileall可以编译python脚本。myapp目录有2个py脚本
# ll myapp total 16 -rw-r--r-- 1 yoo staff 118B 2 26 23:03 example.py -rw-r--r-- 1 yoo staff 43B 2 26 23:03 hello.py
编译脚本
# python -m compileall myapp Listing 'myapp'... Compiling 'myapp/example.py'... Compiling 'myapp/hello.py'...
查看编译结果
tree myapp -L 3 myapp ├── __pycache__ │ ├── example.cpython-38.pyc │ └── hello.cpython-38.pyc ├── example.py └── hello.py 1 directory, 4 files 复制代码
10. 压缩和解压
创建和解压tar包
# python -m tarfile -c myapp.tar myapp # 创建myapp.tar 压缩包 # python -m tarfile -e myapp.tar myapp2 # 解压myapp.tar 到 myapp2目录
使用gzip压缩文件
# python -m gizp sample.py # python -m gzip -d sample.py.gz
使用zip打包文件
# python -m zipfile -c myapp.zip myapp # python -m zipfile -e myapp.zip myapp2
注意: zipfile和zipapp不一样, 后则是生成一个可以执行的app
11. telnet 工具
没有telnet工具的python容器中可以这样:
# python -m telnetlib -d redis 6379 # 连接redis monitor Telnet(redis,6379): send b'monitor\n' Telnet(redis,6379): recv b'-NOAUTH Authentication required.\r\n' -NOAUTH Authentication required.
还有 nntplib && ftplib 两个工具，应该很少使用，就不介绍了
12. 性能和调试工具
自带的timeit可以测试脚本的性能数据
# python -m timeit '"-".join([str(n) for n in range(100) if n%2 == 0])' # 取模求偶数 20000 loops, best of 5: 12.5 usec per loop # python -m timeit '"-".join([str(n) for n in range(0,100,2)])' # 步进 50000 loops, best of 5: 8.85 usec per loop # python -m timeit '"-".join([str(n) for n in range(100) if n&1 == 0])' # 位运算判断奇偶 20000 loops, best of 5: 14.3 usec per loop
不科学1: 位运算竟然比取模慢？
如果不是一个字符串而是一个脚本：
def test_normal(): tmp = "" for x in range(100): if x % 2 == 0: if tmp: tmp = tmp+"-"+str(x) else: tmp = str(x) return tmp if __name__ == '__main__': print(test_normal())
可以下面方式变通使用
# python -m base64 test_string_join.py | python -m base64 -d | python -m timeit 50000000 loops, best of 5: 5.33 nsec per loop
不科学2: 50000000循环只需要5.33纳秒，而之前的用例20000循环需要12.5微秒
标准库中还有 pdb && profile && pstats 使用比较复杂，暂时就不介绍
pypy3 -m timeit '[{} for n in range(1000)]' WARNING: timeit is a very unreliable tool. use pyperf or something else for real measurements pypy3 -m pip install pyperf pypy3 -m pyperf timeit '[{} for n in range(1000)]' ------------------------------------------------------------ 100000 loops, average of 7: 7.3 +- 0.107 usec per loop (using standard deviation) [tywork@liujunhong_szfsfz_work1 config]$ pypy3 -m pyperf timeit '[{} for n in range(1000)]' ........ Mean +- std dev: 8.42 us +- 0.25 us [tywork@liujunhong_szfsfz_work1 config]$ [tywork@liujunhong_szfsfz_work1 config]$ [tywork@liujunhong_szfsfz_work1 config]$ [tywork@liujunhong_szfsfz_work1 config]$ pypy3 -m pyperf timeit '[dict() for n in range(1000)]' ......... Mean +- std dev: 29.6 us +- 1.1 us
13. pydoc
本地服务方式查看python代码文档
# python -m pydoc -p 8080 # 启动一个web服务 Server ready at http://localhost:8080/ Server commands: [b]rowser, [q]uit server> b
文档效果如图
14. test
执行python自带的测试用例，查看系统支持那些特性
# python -m test.regrtest -u cpu == CPython 2.7.16 (default, Jun 5 2020, 22:59:21) [GCC 4.2.1 Compatible Apple LLVM 11.0.3 (clang-1103.0.29.20) (-macos10.15-objc- == Darwin-19.6.0-x86_64-i386-64bit little-endian == /private/var/folders/mv/3vgd3mdx2453clfcst7qlm280000gn/T/test_python_13470 == CPU count: 12 Run tests sequentially 0:00:00 load avg: 2.53 [ 1/404] test_grammar ... = Tests result: FAILURE == 363 tests OK. 5 tests failed: test_import test_posix test_py_compile test_rlcompleter test_scriptpackages 36 tests skipped: test_al test_bsddb test_bsddb3 test_cd test_cl test_codecmaps_cn test_codecmaps_hk test_codecmaps_jp test_codecmaps_kr test_codecmaps_tw test_curses test_epoll test_gdb test_gdbm test_gl test_imgfile test_largefile test_linuxaudiodev test_msilib test_ossaudiodev test_poll test_py3kwarn test_smtpnet test_socketserver test_spwd test_startfile test_sunaudiodev test_timeout test_tk test_tools test_ttk_guionly test_urllib2net test_urllibnet test_winreg test_winsound test_zipfile64 2 skips unexpected on darwin: test_spwd test_tools Total duration: 5 min 23 sec Tests result: FAILUR
从测试用例，可以看到osx支持fork，不支持epool和poll。
0:00:47 load avg: 1.79 [138/404] test_fork1 ... 0:00:39 load avg: 1.59 [125/404] test_epoll test_epoll skipped -- test works only on Linux 2.6 ... 0:02:42 load avg: 2.41 [257/404/1] test_poll test_poll skipped -- select.poll not defined -- skipping test_poll 0:02:42 load avg: 2.41 [258/404/1] test_popen -- test_poll skipped
参考链接
- PEP441--Improving Python ZIP Application Support www.python.org/dev/peps/pe…
- ROT13 zh.wikipedia.org/wiki/ROT13
