#!/usr/bin/env python# -*- coding:utf-8 -*-import sys, os, zipfile, tempfile, tarfile, fnmatch;def read_file(fileName): ''' read file and print file line count ''' f = open(fileName, 'r') try: line_list = f.readlines() #read file each line without '\n' #line_list = f.read().splitlines() #line_list = f.read().split('\n') #line_list = [L.rstrip('\n') for L in f.readlines()] print len(line_list) finally: f.close()def read_file_by_chunks(fileName, chunksize=100): file_object = open(fileName, 'rb') while True: chunk = file_object.read(chunksize) if not chunk: break; yield chunk file_object.close()def search_replace_text_infile(stext='', rtext='', input_file=sys.stdin, output_file=sys.stdout): if isinstance(input_file, basestring): ifile = open(input_file, 'r') else: ifile = input_file if isinstance(output_file, basestring): ofile = open(output_file, 'w') else: ofile = output_file for s in ifile: ofile.write(s.replace(stext, rtext)) if isinstance(ifile, basestring): ifile.close() if isinstance(ofile, basestring): ofile.close() def getline(filename, desired_line_number): if desired_line_number < 1: return '' for current_line, line in enumerate(open(filename, 'rU')): if desired_line_number-1 == current_line: return line.rstrip('\n') return ''def linecount_w(filename): sys_cmd = 'wc -l ' + filename return int(os.popen(sys_cmd).read().split()[0]) def linecount_1(filename): return len(open(filename, 'r').readlines()) def linecount_2(filename): linecount = -1 for linecount, line in enumerate(open(filename, 'r')): pass return linecount+1def linecount_3(filename): linecount = 0 f = open(filename, 'r') while True: chunk = f.read(65535) if not chunk: break linecount += chunk.count('\n') return linecountdef words_of_file_in_firstline(filename, line_to_words=str.split): firstline = getline(filename, 1) for word in line_to_words(firstline): yield word def read_from_zip_file(filename): zipf = zipfile.ZipFile(filename, 'r') for fname in zipf.namelist(): bytes = zipf.read(fname) print 'File %s in %s has %d bytes' % (fname, filename, len(bytes)) zipf.close()def just_for_fun(): #create a temp file with zip suffix handle, tmpFileName = tempfile.mkstemp('.zip') os.close(handle) #open temp zip file tmpZfile = zipfile.ZipFile(tmpFileName, 'w') #write something to temp zip file #paremeter 1:the name of the file in temp file #parameter 2:The file contents is the string 'bytes' tmpZfile.writestr('hello.py', 'def f(): \ return "hello world from " + __file__\n') tmpZfile.close() #set python module search path #put temp zip file into first one sys.path.insert(0, tmpFileName) #import 'hello' module import hello #call hello module's f function print hello.f() os.unlink(tmpFileName) try: from cStringIO import StringIOexcept ImportError: from StringIO import StringIOclass ZipString(zipfile.ZipFile): ''' read zip file content from a string ''' def __init__(self, dataString): zipfile.ZipFile.__init__(self, StringIO(dataString))def make_tar(source_folder, dest_folder, compression='bz2'): if compression: file_ext = '.' + compression compressionPara = ':' + compression else: file_ext = '' compressionPara = '' arcname = os.path.basename(source_folder) dest_file = "%s.tar%s" % (arcname, file_ext) dest_path = os.path.join(dest_folder, dest_file) out = tarfile.TarFile.open(dest_path, 'w'+compressionPara) out.add(source_folder, arcname) out.close() return dest_pathCHUNK_SIZE = 16 * 1024def adapte_file(fileObj): ''' use file-like object to adapte a real file object ''' if isinstance(fileObj, file): return fileObj tmpFileObj = tempfile.TemporaryFile() while True: data = fileObj.read(CHUNK_SIZE) if not data: break tmpFileObj.write(data) fileObj.close() tmpFileObj.seek(0) return tmpFileObjdef all_files(rootPath, patterns='*', single_level=False): patterns = patterns.split(';') for path, dirs, files in os.walk(rootPath): files.sort() for file in files: for pattern in patterns: #test whether filename matchs pattern if fnmatch.fnmatch(file, pattern): yield os.path.join(path, file) break if single_level: breakdef swapextensions(rootPath, before, after): if before[:1] != '.': before = '.' + before extLen = -len(before) if after[:1] != '.': after = '.' + after swapCount = 0 for path, dirs, files in os.walk(rootPath): for file in files: if file[extLen:] == before: oldfile = os.path.join(path, file) newfile = oldfile[:extLen] + after os.rename(oldfile, newfile) swapCount += 1 return swapCountdef search_file(filename, searchPath, pathsep=os.pathsep): for path in searchPath.split(pathsep): candidate = os.path.join(path, filename) if os.path.isfile(candidate): return os.path.abspath(candidate)def addPythonSearchPath(newPath): ''' add new path to module search path of python return: 1 - success 0 - added path already on sys.path -1 - added path doesn't exist ''' if not os.path.exists(newPath): return -1 newPath = os.path.abspath(newPath) if sys.platform == 'win32': newPath = newPath.lower() for searchPath in sys.path: searchPath = os.path.abspath(searchPath) if sys.platform == 'win32': searchPath = searchPath.lower() else: if newPath in (searchPath, searchPath + os.sep): return 0 sys.path.append(newPath) return 1if __name__ == '__main__': read_file('apache_log') totalbytes = 0 for chunk in read_file_by_chunks('twittericon.png'): totalbytes += len(chunk) print 'twittericon.png file size is %d bytes' % totalbytes #search_replace_text_infile('who', '***') desired_line_number = 1 print 'The %d line in "apache_log" is "%s"' % (desired_line_number, getline('apache_log', desired_line_number)) import linecache #also relate clearcache, checkcache print 'The %d line in "sample.txt" is "%s"' % (desired_line_number, linecache.getline('sample.txt', desired_line_number).rstrip('\n')) for f in linecount_w, linecount_1, linecount_2, linecount_3: print f.__name__, f('apache_log') wordlist = [] for word in words_of_file_in_firstline('apache_log'): #revert each word wordlist.append(word[::-1]) print ' '.join(wordlist) read_from_zip_file('Archive.zip') just_for_fun() #print make_tar('./OCP', '.') for path in all_files('./OCP', '*.py'): print path path = './OCP' before = 'html' after = 'htm' print 'the count of swap extensions from %s to %s at path "%s" is %d' % (before, after, path, swapextensions(path, before, after)) searchpath = '/bin' + os.pathsep + '/usr/bin' find_file = search_file('ls', searchpath) if find_file: print 'File "ls" found at %s.' % find_file else: print 'File "ls" not found.' print 'origin search path:' for x in sys.path: print x print "add new path to module search path of python, result:%d" % addPythonSearchPath('./OCP') print 'New search path:' for x in sys.path: print x
