파이썬에서 플러그인 작성하기

      
def path(fullpath, pattern="*", action=(lambda rec: print_rec(rec))):
    """이 함수는 경로(fullpath), 셸 패턴(pattern), action 콜백을 받는다.
    이 함수는 체크섬을 계산하기 위해 좀 더 늦은 pathattr 함수를 사용한다.
    """ 
    for rec in pathattr(fullpath):
        for new_record in match(pattern, rec):  # 필터를 적용한다.
            action(new_record)  # 객체 생성을 위해 람다 콜백을 적용한다.
       

      from pathtool import path
      path("/tmp", pattern="*.mp3", action=(lambda rec: print_rec(rec)))
      

       
#!/usr/bin/env python
# encoding: utf-8
"""
pathtool-cli.py 0.1

파일 시스템을 돌아다니는 명령행 도구
plugin 디렉터리에서 Action plugins 콜백을 얻는다.

action=(lambda rec: print_rec(rec))

"""

from pathtool import path
import optparse
import re
import os
import sys

try:
    plugin_available = True
    from plugin import *
    from plugin import __all__ # 등록된 플러그인 전체 목록을 얻기 위해
except ImportError:
    plugin_available = False
        
def path_controller():
    descriptionMessage = """
    A command line tool for walking a filesystem.\
    Takes callback 'Action' functions as plugins.\
    
    example: pathtool_cli /tmp print_path_ext
    """
    p = optparse.OptionParser(description=descriptionMessage,
                                prog='pathtool',
                                version='pathtool 0.1.1',
                                usage= '%prog [starting directory][action]')
    p.add_option('--pattern', '-p',
                help='Pattern Match Examples: *.txt, *.iso, music[0-5].mp3\
                plain number defaults to * or match all.  \
                Uses UNIX standard wildcard syntax.',
                default='*')

    p.add_option('--list', '-l',
            action="store_true",
            help='lists available action plugins',
            default=False)
                    
    options, arguments = p.parse_args()
    if options.list:
        try:
            print "Action Plugins Available:"
            if plugin_available:
                for p in __all__:
                    print p
        finally:
            sys.exit(0)
            
    if len(arguments) == 2:
        fullpath = arguments[0]
        try:
            action_plugin = eval(arguments[1])   
            # 플러그인 작성자는 다음과 같은 이름 관례에 따라 메서드를 작성해야 한다.
            #path(fullpath,options.pattern,action=(lambda rec: move_to_tmp.plugin(rec)))
            path(fullpath, options.pattern,action=(lambda rec: action_plugin.plugin(rec)))
        except NameError:
            sys.stderr.write("Plugin Not Found")
            sys.exit(1)
    else:
        print p.print_help()

def main():
    path_controller()

if __name__ == '__main__':
    main()

       

# python pathtool_cli.py
Usage: pathtool [starting directory][action]

     A command line tool for walking a filesystem.    Takes callback 'Action'
functions as plugins.         example: pathtool_cli /tmp print_path_ext

Options:
  --version             show program's version number and exit
  -h, --help            show this help message and exit
  -p PATTERN, --pattern=PATTERN
                        Pattern Match Examples: *.txt, *.iso, music[0-5].mp3
                        plain number defaults to * or match all.
                        Uses UNIX standard wildcard syntax.
  -l, --list            lists available action plugins

# python pathtool_cli.py -l
Action Plugins Available:
move_to_tmp
print_file_path_ext

# python pathtool_cli.py /tmp print_file_path_ext
/tmp/foo0.txt | foo0.txt | .txt
/tmp/foo1.txt | foo1.txt | .txt
/tmp/foo10.txt | foo10.txt | .txt
/tmp/foo2.txt | foo2.txt | .txt
/tmp/foo3.txt | foo3.txt | .txt
/tmp/foo4.txt | foo4.txt | .txt
/tmp/foo5.txt | foo5.txt | .txt
/tmp/foo6.txt | foo6.txt | .txt
/tmp/foo7.txt | foo7.txt | .txt
/tmp/foo8.txt | foo8.txt | .txt
/tmp/foo9.txt | foo9.txt | .txt

    plugin_available = True
    from plugin import *
    from plugin import __all__ # 등록된 플러그인 전체 목록을 얻기 위해
except ImportError:
    plugin_available = False

"""Lists all of the importable plugins"""
__all__ = ["move_to_tmp", "print_file_path_ext"]

action_plugin = eval(arguments[1]) 

#!/usr/bin/env python
# encoding: utf-8
"""
prints path, name, ext, plugin
"""

def plugin(rec, verbose=True):
    """Moves matched files to tmp directory"""
    path = rec["path"]
    filename = rec["filename"]
    ext = rec["ext"]
    print "%s | %s | %s" % (path, filename, ext)

{"path": path, "filename": file, "ext": ext, "size": size,
"unique_id": unique_id, "mtime": mtime, "ctime": ctime}