python实现的用于搜索文件并进行内容替换的类实例

本文实例讲述了python实现的用于搜索文件并进行内容替换的类。分享给大家供大家参考。具体实现方法如下：

#!/usr/bin/python -O
# coding: UTF-8
"""
-replace string in files (recursive)
-display the difference.
v0.2
- search_string can be a re.compile() object -> use re.sub for replacing
v0.1
- initial version
 Useable by a small "client" script, e.g.:
-------------------------------------------------------------------------------
#!/usr/bin/python -O
# coding: UTF-8
import sys, re
#sys.path.insert(0,"/path/to/git/repro/") # Please change path
from replace_in_files import SearchAndReplace
SearchAndReplace(
 search_path = "/to/the/files/",
 # e.g.: simple string replace:
 search_string = 'the old string',
 replace_string = 'the new string',
 # e.g.: Regular expression replacing (used re.sub)
 #search_string = re.compile('{％ url (.*?) ％}'),
 #replace_string = "{％ url '\g<1>' ％}",
 search_only = True, # Display only the difference
 #search_only = False, # write the new content
 file_filter=("*.py",), # fnmatch-Filter
)
-------------------------------------------------------------------------------
:copyleft: 2009-2011 by Jens Diemer
"""
__author__ = "Jens Diemer"
__license__ = """GNU General Public License v3 or above -
http://www.opensource.org/licenses/gpl-license.php"""
__url__ = "http://www.jensdiemer.de"
__version__ = "0.2"
import os, re, time, fnmatch, difflib
# FIXME: see http://stackoverflow.com/questions/4730121/cant-get-an-objects-class-name-in-python
RE_TYPE = type(re.compile(""))
class SearchAndReplace(object):
 def __init__(self, search_path, search_string, replace_string,
                   search_only=True, file_filter=("*.*",)):
   self.search_path = search_path
   self.search_string = search_string
   self.replace_string = replace_string
   self.search_only = search_only
   self.file_filter = file_filter
   assert isinstance(self.file_filter, (list, tuple))
   # FIXME: see http://stackoverflow.com/questions/4730121/cant-get-an-objects-class-name-in-python
   self.is_re = isinstance(self.search_string, RE_TYPE)
   print "Search '％s' in [％s]..." ％ (
     self.search_string, self.search_path
   )
   print "_" * 80
   time_begin = time.time()
   file_count = self.walk()
   print "_" * 80
   print "％s files searched in ％0.2fsec." ％ (
     file_count, (time.time() - time_begin)
   )
 def walk(self):
   file_count = 0
   for root, dirlist, filelist in os.walk(self.search_path):
     if ".svn" in root:
       continue
     for filename in filelist:
       for file_filter in self.file_filter:
         if fnmatch.fnmatch(filename, file_filter):
           self.search_file(os.path.join(root, filename))
           file_count += 1
   return file_count
 def search_file(self, filepath):
   f = file(filepath, "r")
   old_content = f.read()
   f.close()
   if self.is_re or self.search_string in old_content:
     new_content = self.replace_content(old_content, filepath)
     if self.is_re and new_content == old_content:
       return
     print filepath
     self.display_plaintext_diff(old_content, new_content)
 def replace_content(self, old_content, filepath):
   if self.is_re:
     new_content = self.search_string.sub(self.replace_string, old_content)
     if new_content == old_content:
       return old_content
   else:
     new_content = old_content.replace(
       self.search_string, self.replace_string
     )
   if self.search_only != False:
     return new_content
   print "Write new content into ％s..." ％ filepath,
   try:
     f = file(filepath, "w")
     f.write(new_content)
     f.close()
   except IOError, msg:
     print "Error:", msg
   else:
     print "OK"
   print
   return new_content
 def display_plaintext_diff(self, content1, content2):
   """
   Display a diff.
   """
   content1 = content1.splitlines()
   content2 = content2.splitlines()
   diff = difflib.Differ().compare(content1, content2)
   def is_diff_line(line):
     for char in ("-", "+", "?"):
       if line.startswith(char):
         return True
     return False
   print "line | text\n-------------------------------------------"
   old_line = ""
   in_block = False
   old_lineno = lineno = 0
   for line in diff:
     if line.startswith(" ") or line.startswith("+"):
       lineno += 1
     if old_lineno == lineno:
       display_line = "％4s | ％s" ％ ("", line.rstrip())
     else:
       display_line = "％4s | ％s" ％ (lineno, line.rstrip())
     if is_diff_line(line):
       if not in_block:
         print "..."
         # Display previous line
         print old_line
         in_block = True
       print display_line
     else:
       if in_block:
         # Display the next line aber a diff-block
         print display_line
       in_block = False
     old_line = display_line
     old_lineno = lineno
   print "..."
if __name__ == "__main__":
 SearchAndReplace(
   search_path=".",
   # e.g.: simple string replace:
   search_string='the old string',
   replace_string='the new string',
   # e.g.: Regular expression replacing (used re.sub)
   #search_string  = re.compile('{％ url (.*?) ％}'),
   #replace_string = "{％ url '\g<1>' ％}",
   search_only=True, # Display only the difference
#    search_only   = False, # write the new content
   file_filter=("*.py",), # fnmatch-Filter
 )

希望本文所述对大家的Python程序设计有所帮助。