ATM作业讲解:

数据访问层

业务逻辑层

time & datetime模块

 import time

 # print(time.clock()) #返回处理器时间,3.3开始已废弃 , 改成了time.process_time()测量处理器运算时间,不包括sleep时间,不稳定,mac上测不出来
# print(time.altzone) #返回与utc时间的时间差,以秒计算\
# print(time.asctime()) #返回时间格式"Fri Aug 19 11:14:16 2016",
# print(time.localtime()) #返回本地时间 的struct time对象格式
# print(time.gmtime(time.time()-800000)) #返回utc时间的struc时间对象格式 # print(time.asctime(time.localtime())) #返回时间格式"Fri Aug 19 11:14:16 2016",
#print(time.ctime()) #返回Fri Aug 19 12:38:29 2016 格式, 同上 # 日期字符串 转成 时间戳
# string_2_struct = time.strptime("2016/05/22","%Y/%m/%d") #将 日期字符串 转成 struct时间对象格式
# print(string_2_struct)
# #
# struct_2_stamp = time.mktime(string_2_struct) #将struct时间对象转成时间戳
# print(struct_2_stamp) #将时间戳转为字符串格式
# print(time.gmtime(time.time()-86640)) #将utc时间戳转换成struct_time格式
# print(time.strftime("%Y-%m-%d %H:%M:%S",time.gmtime()) ) #将utc struct_time格式转成指定的字符串格式 #时间加减
import datetime # print(datetime.datetime.now()) #返回 2016-08-19 12:47:03.941925
#print(datetime.date.fromtimestamp(time.time()) ) # 时间戳直接转成日期格式 2016-08-19
# print(datetime.datetime.now() )
# print(datetime.datetime.now() + datetime.timedelta(3)) #当前时间+3天
# print(datetime.datetime.now() + datetime.timedelta(-3)) #当前时间-3天
# print(datetime.datetime.now() + datetime.timedelta(hours=3)) #当前时间+3小时
# print(datetime.datetime.now() + datetime.timedelta(minutes=30)) #当前时间+30分 #
# c_time = datetime.datetime.now()
# print(c_time.replace(minute=3,hour=2)) #时间替换
 
Directive Meaning Notes
%a Locale’s abbreviated weekday name.  
%A Locale’s full weekday name.  
%b Locale’s abbreviated month name.  
%B Locale’s full month name.  
%c Locale’s appropriate date and time representation.  
%d Day of the month as a decimal number [01,31].  
%H Hour (24-hour clock) as a decimal number [00,23].  
%I Hour (12-hour clock) as a decimal number [01,12].  
%j Day of the year as a decimal number [001,366].  
%m Month as a decimal number [01,12].  
%M Minute as a decimal number [00,59].  
%p Locale’s equivalent of either AM or PM. (1)
%S Second as a decimal number [00,61]. (2)
%U Week number of the year (Sunday as the first day of the week) as a decimal number [00,53]. All days in a new year preceding the first Sunday are considered to be in week 0. (3)
%w Weekday as a decimal number [0(Sunday),6].  
%W Week number of the year (Monday as the first day of the week) as a decimal number [00,53]. All days in a new year preceding the first Monday are considered to be in week 0. (3)
%x Locale’s appropriate date representation.  
%X Locale’s appropriate time representation.  
%y Year without century as a decimal number [00,99].  
%Y Year with century as a decimal number.  
%z Time zone offset indicating a positive or negative time difference from UTC/GMT of the form +HHMM or -HHMM, where H represents decimal hour digits and M represents decimal minute digits [-23:59, +23:59].  
%Z Time zone name (no characters if no time zone exists).  
%% A literal '%' character.

random模块

随机数

 import random
print(random.random())
print(random.randint(1,5))
print(random.randrange(1,2))

生成随机验证码

 import random

 import string

 str_source = string.ascii_letters + string.digits
print(''.join(random.sample(str_source,7)))
1
2
3
4
5
6
7
8
9
10
import random
checkcode = ''
for in range(4):
    current = random.randrange(0,4)
    if current != i:
        temp = chr(random.randint(65,90))
    else:
        temp = random.randint(0,9)
    checkcode += str(temp)
print checkcode

shutil 模块

高级的 文件、文件夹、压缩包 处理模块

shutil.copyfileobj(fsrc, fdst[, length])
将文件内容拷贝到另一个文件中,可以部分内容

 def copyfileobj(fsrc, fdst, length=16*1024):
"""copy data from file-like object fsrc to file-like object fdst"""
while 1:
buf = fsrc.read(length)
if not buf:
break
fdst.write(buf)

shutil.copyfile(src, dst)
拷贝文件

 def copyfile(src, dst):
"""Copy data from src to dst"""
if _samefile(src, dst):
raise Error("`%s` and `%s` are the same file" % (src, dst)) for fn in [src, dst]:
try:
st = os.stat(fn)
except OSError:
# File most likely does not exist
pass
else:
# XXX What about other special files? (sockets, devices...)
if stat.S_ISFIFO(st.st_mode):
raise SpecialFileError("`%s` is a named pipe" % fn) with open(src, 'rb') as fsrc:
with open(dst, 'wb') as fdst:
copyfileobj(fsrc, fdst)

shutil.copymode(src, dst)
仅拷贝权限。内容、组、用户均不变

 def copymode(src, dst):
"""Copy mode bits from src to dst"""
if hasattr(os, 'chmod'):
st = os.stat(src)
mode = stat.S_IMODE(st.st_mode)
os.chmod(dst, mode)

shutil.copystat(src, dst)
拷贝状态的信息,包括:mode bits, atime, mtime, flags

 def copystat(src, dst):
"""Copy all stat info (mode bits, atime, mtime, flags) from src to dst"""
st = os.stat(src)
mode = stat.S_IMODE(st.st_mode)
if hasattr(os, 'utime'):
os.utime(dst, (st.st_atime, st.st_mtime))
if hasattr(os, 'chmod'):
os.chmod(dst, mode)
if hasattr(os, 'chflags') and hasattr(st, 'st_flags'):
try:
os.chflags(dst, st.st_flags)
except OSError, why:
for err in 'EOPNOTSUPP', 'ENOTSUP':
if hasattr(errno, err) and why.errno == getattr(errno, err):
break
else:
raise

shutil.copy(src, dst)
拷贝文件和权限

 def copy(src, dst):
"""Copy data and mode bits ("cp src dst"). The destination may be a directory. """
if os.path.isdir(dst):
dst = os.path.join(dst, os.path.basename(src))
copyfile(src, dst)
copymode(src, dst)

shutil.copy2(src, dst)
拷贝文件和状态信息

 def copy2(src, dst):
"""Copy data and all stat info ("cp -p src dst"). The destination may be a directory. """
if os.path.isdir(dst):
dst = os.path.join(dst, os.path.basename(src))
copyfile(src, dst)
copystat(src, dst)

shutil.ignore_patterns(*patterns)
shutil.copytree(src, dst, symlinks=False, ignore=None)
递归的去拷贝文件

例如:copytree(source, destination, ignore=ignore_patterns('*.pyc', 'tmp*'))

 def ignore_patterns(*patterns):
"""Function that can be used as copytree() ignore parameter. Patterns is a sequence of glob-style patterns
that are used to exclude files"""
def _ignore_patterns(path, names):
ignored_names = []
for pattern in patterns:
ignored_names.extend(fnmatch.filter(names, pattern))
return set(ignored_names)
return _ignore_patterns def copytree(src, dst, symlinks=False, ignore=None):
"""Recursively copy a directory tree using copy2(). The destination directory must not already exist.
If exception(s) occur, an Error is raised with a list of reasons. If the optional symlinks flag is true, symbolic links in the
source tree result in symbolic links in the destination tree; if
it is false, the contents of the files pointed to by symbolic
links are copied. The optional ignore argument is a callable. If given, it
is called with the `src` parameter, which is the directory
being visited by copytree(), and `names` which is the list of
`src` contents, as returned by os.listdir(): callable(src, names) -> ignored_names Since copytree() is called recursively, the callable will be
called once for each directory that is copied. It returns a
list of names relative to the `src` directory that should
not be copied. XXX Consider this example code rather than the ultimate tool. """
names = os.listdir(src)
if ignore is not None:
ignored_names = ignore(src, names)
else:
ignored_names = set() os.makedirs(dst)
errors = []
for name in names:
if name in ignored_names:
continue
srcname = os.path.join(src, name)
dstname = os.path.join(dst, name)
try:
if symlinks and os.path.islink(srcname):
linkto = os.readlink(srcname)
os.symlink(linkto, dstname)
elif os.path.isdir(srcname):
copytree(srcname, dstname, symlinks, ignore)
else:
# Will raise a SpecialFileError for unsupported file types
copy2(srcname, dstname)
# catch the Error from the recursive copytree so that we can
# continue with other files
except Error, err:
errors.extend(err.args[0])
except EnvironmentError, why:
errors.append((srcname, dstname, str(why)))
try:
copystat(src, dst)
except OSError, why:
if WindowsError is not None and isinstance(why, WindowsError):
# Copying file access times may fail on Windows
pass
else:
errors.append((src, dst, str(why)))
if errors:
raise Error, errors

shutil.rmtree(path[, ignore_errors[, onerror]])
递归的去删除文件

 def rmtree(path, ignore_errors=False, onerror=None):
"""Recursively delete a directory tree. If ignore_errors is set, errors are ignored; otherwise, if onerror
is set, it is called to handle the error with arguments (func,
path, exc_info) where func is os.listdir, os.remove, or os.rmdir;
path is the argument to that function that caused it to fail; and
exc_info is a tuple returned by sys.exc_info(). If ignore_errors
is false and onerror is None, an exception is raised. """
if ignore_errors:
def onerror(*args):
pass
elif onerror is None:
def onerror(*args):
raise
try:
if os.path.islink(path):
# symlinks to directories are forbidden, see bug #1669
raise OSError("Cannot call rmtree on a symbolic link")
except OSError:
onerror(os.path.islink, path, sys.exc_info())
# can't continue even if onerror hook returns
return
names = []
try:
names = os.listdir(path)
except os.error, err:
onerror(os.listdir, path, sys.exc_info())
for name in names:
fullname = os.path.join(path, name)
try:
mode = os.lstat(fullname).st_mode
except os.error:
mode = 0
if stat.S_ISDIR(mode):
rmtree(fullname, ignore_errors, onerror)
else:
try:
os.remove(fullname)
except os.error, err:
onerror(os.remove, fullname, sys.exc_info())
try:
os.rmdir(path)
except os.error:
onerror(os.rmdir, path, sys.exc_info())

shutil.move(src, dst)
递归的去移动文件

 def move(src, dst):
"""Recursively move a file or directory to another location. This is
similar to the Unix "mv" command. If the destination is a directory or a symlink to a directory, the source
is moved inside the directory. The destination path must not already
exist. If the destination already exists but is not a directory, it may be
overwritten depending on os.rename() semantics. If the destination is on our current filesystem, then rename() is used.
Otherwise, src is copied to the destination and then removed.
A lot more could be done here... A look at a mv.c shows a lot of
the issues this implementation glosses over. """
real_dst = dst
if os.path.isdir(dst):
if _samefile(src, dst):
# We might be on a case insensitive filesystem,
# perform the rename anyway.
os.rename(src, dst)
return real_dst = os.path.join(dst, _basename(src))
if os.path.exists(real_dst):
raise Error, "Destination path '%s' already exists" % real_dst
try:
os.rename(src, real_dst)
except OSError:
if os.path.isdir(src):
if _destinsrc(src, dst):
raise Error, "Cannot move a directory '%s' into itself '%s'." % (src, dst)
copytree(src, real_dst, symlinks=True)
rmtree(src)
else:
copy2(src, real_dst)
os.unlink(src)

shutil.make_archive(base_name, format,...)

创建压缩包并返回文件路径,例如:zip、tar

  • base_name: 压缩包的文件名,也可以是压缩包的路径。只是文件名时,则保存至当前目录,否则保存至指定路径,
    如:www                        =>保存至当前路径
    如:/Users/wupeiqi/www =>保存至/Users/wupeiqi/
  • format: 压缩包种类,“zip”, “tar”, “bztar”,“gztar”
  • root_dir: 要压缩的文件夹路径(默认当前目录)
  • owner: 用户,默认当前用户
  • group: 组,默认当前组
  • logger: 用于记录日志,通常是logging.Logger对象
1
2
3
4
5
6
7
8
9
#将 /Users/wupeiqi/Downloads/test 下的文件打包放置当前程序目录
 
import shutil
ret = shutil.make_archive("wwwwwwwwww"'gztar', root_dir='/Users/wupeiqi/Downloads/test')
 
 
#将 /Users/wupeiqi/Downloads/test 下的文件打包放置 /Users/wupeiqi/目录
import shutil
ret = shutil.make_archive("/Users/wupeiqi/wwwwwwwwww"'gztar', root_dir='/Users/wupeiqi/Downloads/test')
 

shutil 对压缩包的处理是调用 ZipFile 和 TarFile 两个模块来进行的,详细:

 import zipfile

 # 压缩
z = zipfile.ZipFile('laxi.zip', 'w')
z.write('a.log')
z.write('data.data')
z.close() # 解压
z = zipfile.ZipFile('laxi.zip', 'r')
z.extractall()
z.close()

zipfile 压缩解压

 import tarfile

 # 压缩
tar = tarfile.open('your.tar','w')
tar.add('/Users/wupeiqi/PycharmProjects/bbs2.zip', arcname='bbs2.zip')
tar.add('/Users/wupeiqi/PycharmProjects/cmdb.zip', arcname='cmdb.zip')
tar.close() # 解压
tar = tarfile.open('your.tar','r')
tar.extractall() # 可设置解压地址
tar.close()

tarfile 压缩解压

 class ZipFile(object):
""" Class with methods to open, read, write, close, list zip files. z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=False) file: Either the path to the file, or a file-like object.
If it is a path, the file will be opened and closed by ZipFile.
mode: The mode can be either read "r", write "w" or append "a".
compression: ZIP_STORED (no compression) or ZIP_DEFLATED (requires zlib).
allowZip64: if True ZipFile will create files with ZIP64 extensions when
needed, otherwise it will raise an exception when this would
be necessary. """ fp = None # Set here since __del__ checks it def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=False):
"""Open the ZIP file with mode read "r", write "w" or append "a"."""
if mode not in ("r", "w", "a"):
raise RuntimeError('ZipFile() requires mode "r", "w", or "a"') if compression == ZIP_STORED:
pass
elif compression == ZIP_DEFLATED:
if not zlib:
raise RuntimeError,\
"Compression requires the (missing) zlib module"
else:
raise RuntimeError, "That compression method is not supported" self._allowZip64 = allowZip64
self._didModify = False
self.debug = 0 # Level of printing: 0 through 3
self.NameToInfo = {} # Find file info given name
self.filelist = [] # List of ZipInfo instances for archive
self.compression = compression # Method of compression
self.mode = key = mode.replace('b', '')[0]
self.pwd = None
self._comment = '' # Check if we were passed a file-like object
if isinstance(file, basestring):
self._filePassed = 0
self.filename = file
modeDict = {'r' : 'rb', 'w': 'wb', 'a' : 'r+b'}
try:
self.fp = open(file, modeDict[mode])
except IOError:
if mode == 'a':
mode = key = 'w'
self.fp = open(file, modeDict[mode])
else:
raise
else:
self._filePassed = 1
self.fp = file
self.filename = getattr(file, 'name', None) try:
if key == 'r':
self._RealGetContents()
elif key == 'w':
# set the modified flag so central directory gets written
# even if no files are added to the archive
self._didModify = True
elif key == 'a':
try:
# See if file is a zip file
self._RealGetContents()
# seek to start of directory and overwrite
self.fp.seek(self.start_dir, 0)
except BadZipfile:
# file is not a zip file, just append
self.fp.seek(0, 2) # set the modified flag so central directory gets written
# even if no files are added to the archive
self._didModify = True
else:
raise RuntimeError('Mode must be "r", "w" or "a"')
except:
fp = self.fp
self.fp = None
if not self._filePassed:
fp.close()
raise def __enter__(self):
return self def __exit__(self, type, value, traceback):
self.close() def _RealGetContents(self):
"""Read in the table of contents for the ZIP file."""
fp = self.fp
try:
endrec = _EndRecData(fp)
except IOError:
raise BadZipfile("File is not a zip file")
if not endrec:
raise BadZipfile, "File is not a zip file"
if self.debug > 1:
print endrec
size_cd = endrec[_ECD_SIZE] # bytes in central directory
offset_cd = endrec[_ECD_OFFSET] # offset of central directory
self._comment = endrec[_ECD_COMMENT] # archive comment # "concat" is zero, unless zip was concatenated to another file
concat = endrec[_ECD_LOCATION] - size_cd - offset_cd
if endrec[_ECD_SIGNATURE] == stringEndArchive64:
# If Zip64 extension structures are present, account for them
concat -= (sizeEndCentDir64 + sizeEndCentDir64Locator) if self.debug > 2:
inferred = concat + offset_cd
print "given, inferred, offset", offset_cd, inferred, concat
# self.start_dir: Position of start of central directory
self.start_dir = offset_cd + concat
fp.seek(self.start_dir, 0)
data = fp.read(size_cd)
fp = cStringIO.StringIO(data)
total = 0
while total < size_cd:
centdir = fp.read(sizeCentralDir)
if len(centdir) != sizeCentralDir:
raise BadZipfile("Truncated central directory")
centdir = struct.unpack(structCentralDir, centdir)
if centdir[_CD_SIGNATURE] != stringCentralDir:
raise BadZipfile("Bad magic number for central directory")
if self.debug > 2:
print centdir
filename = fp.read(centdir[_CD_FILENAME_LENGTH])
# Create ZipInfo instance to store file information
x = ZipInfo(filename)
x.extra = fp.read(centdir[_CD_EXTRA_FIELD_LENGTH])
x.comment = fp.read(centdir[_CD_COMMENT_LENGTH])
x.header_offset = centdir[_CD_LOCAL_HEADER_OFFSET]
(x.create_version, x.create_system, x.extract_version, x.reserved,
x.flag_bits, x.compress_type, t, d,
x.CRC, x.compress_size, x.file_size) = centdir[1:12]
x.volume, x.internal_attr, x.external_attr = centdir[15:18]
# Convert date/time code to (year, month, day, hour, min, sec)
x._raw_time = t
x.date_time = ( (d>>9)+1980, (d>>5)&0xF, d&0x1F,
t>>11, (t>>5)&0x3F, (t&0x1F) * 2 ) x._decodeExtra()
x.header_offset = x.header_offset + concat
x.filename = x._decodeFilename()
self.filelist.append(x)
self.NameToInfo[x.filename] = x # update total bytes read from central directory
total = (total + sizeCentralDir + centdir[_CD_FILENAME_LENGTH]
+ centdir[_CD_EXTRA_FIELD_LENGTH]
+ centdir[_CD_COMMENT_LENGTH]) if self.debug > 2:
print "total", total def namelist(self):
"""Return a list of file names in the archive."""
l = []
for data in self.filelist:
l.append(data.filename)
return l def infolist(self):
"""Return a list of class ZipInfo instances for files in the
archive."""
return self.filelist def printdir(self):
"""Print a table of contents for the zip file."""
print "%-46s %19s %12s" % ("File Name", "Modified ", "Size")
for zinfo in self.filelist:
date = "%d-%02d-%02d %02d:%02d:%02d" % zinfo.date_time[:6]
print "%-46s %s %12d" % (zinfo.filename, date, zinfo.file_size) def testzip(self):
"""Read all the files and check the CRC."""
chunk_size = 2 ** 20
for zinfo in self.filelist:
try:
# Read by chunks, to avoid an OverflowError or a
# MemoryError with very large embedded files.
with self.open(zinfo.filename, "r") as f:
while f.read(chunk_size): # Check CRC-32
pass
except BadZipfile:
return zinfo.filename def getinfo(self, name):
"""Return the instance of ZipInfo given 'name'."""
info = self.NameToInfo.get(name)
if info is None:
raise KeyError(
'There is no item named %r in the archive' % name) return info def setpassword(self, pwd):
"""Set default password for encrypted files."""
self.pwd = pwd @property
def comment(self):
"""The comment text associated with the ZIP file."""
return self._comment @comment.setter
def comment(self, comment):
# check for valid comment length
if len(comment) > ZIP_MAX_COMMENT:
import warnings
warnings.warn('Archive comment is too long; truncating to %d bytes'
% ZIP_MAX_COMMENT, stacklevel=2)
comment = comment[:ZIP_MAX_COMMENT]
self._comment = comment
self._didModify = True def read(self, name, pwd=None):
"""Return file bytes (as a string) for name."""
return self.open(name, "r", pwd).read() def open(self, name, mode="r", pwd=None):
"""Return file-like object for 'name'."""
if mode not in ("r", "U", "rU"):
raise RuntimeError, 'open() requires mode "r", "U", or "rU"'
if not self.fp:
raise RuntimeError, \
"Attempt to read ZIP archive that was already closed" # Only open a new file for instances where we were not
# given a file object in the constructor
if self._filePassed:
zef_file = self.fp
should_close = False
else:
zef_file = open(self.filename, 'rb')
should_close = True try:
# Make sure we have an info object
if isinstance(name, ZipInfo):
# 'name' is already an info object
zinfo = name
else:
# Get info object for name
zinfo = self.getinfo(name) zef_file.seek(zinfo.header_offset, 0) # Skip the file header:
fheader = zef_file.read(sizeFileHeader)
if len(fheader) != sizeFileHeader:
raise BadZipfile("Truncated file header")
fheader = struct.unpack(structFileHeader, fheader)
if fheader[_FH_SIGNATURE] != stringFileHeader:
raise BadZipfile("Bad magic number for file header") fname = zef_file.read(fheader[_FH_FILENAME_LENGTH])
if fheader[_FH_EXTRA_FIELD_LENGTH]:
zef_file.read(fheader[_FH_EXTRA_FIELD_LENGTH]) if fname != zinfo.orig_filename:
raise BadZipfile, \
'File name in directory "%s" and header "%s" differ.' % (
zinfo.orig_filename, fname) # check for encrypted flag & handle password
is_encrypted = zinfo.flag_bits & 0x1
zd = None
if is_encrypted:
if not pwd:
pwd = self.pwd
if not pwd:
raise RuntimeError, "File %s is encrypted, " \
"password required for extraction" % name zd = _ZipDecrypter(pwd)
# The first 12 bytes in the cypher stream is an encryption header
# used to strengthen the algorithm. The first 11 bytes are
# completely random, while the 12th contains the MSB of the CRC,
# or the MSB of the file time depending on the header type
# and is used to check the correctness of the password.
bytes = zef_file.read(12)
h = map(zd, bytes[0:12])
if zinfo.flag_bits & 0x8:
# compare against the file type from extended local headers
check_byte = (zinfo._raw_time >> 8) & 0xff
else:
# compare against the CRC otherwise
check_byte = (zinfo.CRC >> 24) & 0xff
if ord(h[11]) != check_byte:
raise RuntimeError("Bad password for file", name) return ZipExtFile(zef_file, mode, zinfo, zd,
close_fileobj=should_close)
except:
if should_close:
zef_file.close()
raise def extract(self, member, path=None, pwd=None):
"""Extract a member from the archive to the current working directory,
using its full name. Its file information is extracted as accurately
as possible. `member' may be a filename or a ZipInfo object. You can
specify a different directory using `path'.
"""
if not isinstance(member, ZipInfo):
member = self.getinfo(member) if path is None:
path = os.getcwd() return self._extract_member(member, path, pwd) def extractall(self, path=None, members=None, pwd=None):
"""Extract all members from the archive to the current working
directory. `path' specifies a different directory to extract to.
`members' is optional and must be a subset of the list returned
by namelist().
"""
if members is None:
members = self.namelist() for zipinfo in members:
self.extract(zipinfo, path, pwd) def _extract_member(self, member, targetpath, pwd):
"""Extract the ZipInfo object 'member' to a physical
file on the path targetpath.
"""
# build the destination pathname, replacing
# forward slashes to platform specific separators.
arcname = member.filename.replace('/', os.path.sep) if os.path.altsep:
arcname = arcname.replace(os.path.altsep, os.path.sep)
# interpret absolute pathname as relative, remove drive letter or
# UNC path, redundant separators, "." and ".." components.
arcname = os.path.splitdrive(arcname)[1]
arcname = os.path.sep.join(x for x in arcname.split(os.path.sep)
if x not in ('', os.path.curdir, os.path.pardir))
if os.path.sep == '\\':
# filter illegal characters on Windows
illegal = ':<>|"?*'
if isinstance(arcname, unicode):
table = {ord(c): ord('_') for c in illegal}
else:
table = string.maketrans(illegal, '_' * len(illegal))
arcname = arcname.translate(table)
# remove trailing dots
arcname = (x.rstrip('.') for x in arcname.split(os.path.sep))
arcname = os.path.sep.join(x for x in arcname if x) targetpath = os.path.join(targetpath, arcname)
targetpath = os.path.normpath(targetpath) # Create all upper directories if necessary.
upperdirs = os.path.dirname(targetpath)
if upperdirs and not os.path.exists(upperdirs):
os.makedirs(upperdirs) if member.filename[-1] == '/':
if not os.path.isdir(targetpath):
os.mkdir(targetpath)
return targetpath with self.open(member, pwd=pwd) as source, \
file(targetpath, "wb") as target:
shutil.copyfileobj(source, target) return targetpath def _writecheck(self, zinfo):
"""Check for errors before writing a file to the archive."""
if zinfo.filename in self.NameToInfo:
import warnings
warnings.warn('Duplicate name: %r' % zinfo.filename, stacklevel=3)
if self.mode not in ("w", "a"):
raise RuntimeError, 'write() requires mode "w" or "a"'
if not self.fp:
raise RuntimeError, \
"Attempt to write ZIP archive that was already closed"
if zinfo.compress_type == ZIP_DEFLATED and not zlib:
raise RuntimeError, \
"Compression requires the (missing) zlib module"
if zinfo.compress_type not in (ZIP_STORED, ZIP_DEFLATED):
raise RuntimeError, \
"That compression method is not supported"
if not self._allowZip64:
requires_zip64 = None
if len(self.filelist) >= ZIP_FILECOUNT_LIMIT:
requires_zip64 = "Files count"
elif zinfo.file_size > ZIP64_LIMIT:
requires_zip64 = "Filesize"
elif zinfo.header_offset > ZIP64_LIMIT:
requires_zip64 = "Zipfile size"
if requires_zip64:
raise LargeZipFile(requires_zip64 +
" would require ZIP64 extensions") def write(self, filename, arcname=None, compress_type=None):
"""Put the bytes from filename into the archive under the name
arcname."""
if not self.fp:
raise RuntimeError(
"Attempt to write to ZIP archive that was already closed") st = os.stat(filename)
isdir = stat.S_ISDIR(st.st_mode)
mtime = time.localtime(st.st_mtime)
date_time = mtime[0:6]
# Create ZipInfo instance to store file information
if arcname is None:
arcname = filename
arcname = os.path.normpath(os.path.splitdrive(arcname)[1])
while arcname[0] in (os.sep, os.altsep):
arcname = arcname[1:]
if isdir:
arcname += '/'
zinfo = ZipInfo(arcname, date_time)
zinfo.external_attr = (st[0] & 0xFFFF) << 16L # Unix attributes
if compress_type is None:
zinfo.compress_type = self.compression
else:
zinfo.compress_type = compress_type zinfo.file_size = st.st_size
zinfo.flag_bits = 0x00
zinfo.header_offset = self.fp.tell() # Start of header bytes self._writecheck(zinfo)
self._didModify = True if isdir:
zinfo.file_size = 0
zinfo.compress_size = 0
zinfo.CRC = 0
zinfo.external_attr |= 0x10 # MS-DOS directory flag
self.filelist.append(zinfo)
self.NameToInfo[zinfo.filename] = zinfo
self.fp.write(zinfo.FileHeader(False))
return with open(filename, "rb") as fp:
# Must overwrite CRC and sizes with correct data later
zinfo.CRC = CRC = 0
zinfo.compress_size = compress_size = 0
# Compressed size can be larger than uncompressed size
zip64 = self._allowZip64 and \
zinfo.file_size * 1.05 > ZIP64_LIMIT
self.fp.write(zinfo.FileHeader(zip64))
if zinfo.compress_type == ZIP_DEFLATED:
cmpr = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
zlib.DEFLATED, -15)
else:
cmpr = None
file_size = 0
while 1:
buf = fp.read(1024 * 8)
if not buf:
break
file_size = file_size + len(buf)
CRC = crc32(buf, CRC) & 0xffffffff
if cmpr:
buf = cmpr.compress(buf)
compress_size = compress_size + len(buf)
self.fp.write(buf)
if cmpr:
buf = cmpr.flush()
compress_size = compress_size + len(buf)
self.fp.write(buf)
zinfo.compress_size = compress_size
else:
zinfo.compress_size = file_size
zinfo.CRC = CRC
zinfo.file_size = file_size
if not zip64 and self._allowZip64:
if file_size > ZIP64_LIMIT:
raise RuntimeError('File size has increased during compressing')
if compress_size > ZIP64_LIMIT:
raise RuntimeError('Compressed size larger than uncompressed size')
# Seek backwards and write file header (which will now include
# correct CRC and file sizes)
position = self.fp.tell() # Preserve current position in file
self.fp.seek(zinfo.header_offset, 0)
self.fp.write(zinfo.FileHeader(zip64))
self.fp.seek(position, 0)
self.filelist.append(zinfo)
self.NameToInfo[zinfo.filename] = zinfo def writestr(self, zinfo_or_arcname, bytes, compress_type=None):
"""Write a file into the archive. The contents is the string
'bytes'. 'zinfo_or_arcname' is either a ZipInfo instance or
the name of the file in the archive."""
if not isinstance(zinfo_or_arcname, ZipInfo):
zinfo = ZipInfo(filename=zinfo_or_arcname,
date_time=time.localtime(time.time())[:6]) zinfo.compress_type = self.compression
if zinfo.filename[-1] == '/':
zinfo.external_attr = 0o40775 << 16 # drwxrwxr-x
zinfo.external_attr |= 0x10 # MS-DOS directory flag
else:
zinfo.external_attr = 0o600 << 16 # ?rw-------
else:
zinfo = zinfo_or_arcname if not self.fp:
raise RuntimeError(
"Attempt to write to ZIP archive that was already closed") if compress_type is not None:
zinfo.compress_type = compress_type zinfo.file_size = len(bytes) # Uncompressed size
zinfo.header_offset = self.fp.tell() # Start of header bytes
self._writecheck(zinfo)
self._didModify = True
zinfo.CRC = crc32(bytes) & 0xffffffff # CRC-32 checksum
if zinfo.compress_type == ZIP_DEFLATED:
co = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
zlib.DEFLATED, -15)
bytes = co.compress(bytes) + co.flush()
zinfo.compress_size = len(bytes) # Compressed size
else:
zinfo.compress_size = zinfo.file_size
zip64 = zinfo.file_size > ZIP64_LIMIT or \
zinfo.compress_size > ZIP64_LIMIT
if zip64 and not self._allowZip64:
raise LargeZipFile("Filesize would require ZIP64 extensions")
self.fp.write(zinfo.FileHeader(zip64))
self.fp.write(bytes)
if zinfo.flag_bits & 0x08:
# Write CRC and file sizes after the file data
fmt = '<LQQ' if zip64 else '<LLL'
self.fp.write(struct.pack(fmt, zinfo.CRC, zinfo.compress_size,
zinfo.file_size))
self.fp.flush()
self.filelist.append(zinfo)
self.NameToInfo[zinfo.filename] = zinfo def __del__(self):
"""Call the "close()" method in case the user forgot."""
self.close() def close(self):
"""Close the file, and for mode "w" and "a" write the ending
records."""
if self.fp is None:
return try:
if self.mode in ("w", "a") and self._didModify: # write ending records
pos1 = self.fp.tell()
for zinfo in self.filelist: # write central directory
dt = zinfo.date_time
dosdate = (dt[0] - 1980) << 9 | dt[1] << 5 | dt[2]
dostime = dt[3] << 11 | dt[4] << 5 | (dt[5] // 2)
extra = []
if zinfo.file_size > ZIP64_LIMIT \
or zinfo.compress_size > ZIP64_LIMIT:
extra.append(zinfo.file_size)
extra.append(zinfo.compress_size)
file_size = 0xffffffff
compress_size = 0xffffffff
else:
file_size = zinfo.file_size
compress_size = zinfo.compress_size if zinfo.header_offset > ZIP64_LIMIT:
extra.append(zinfo.header_offset)
header_offset = 0xffffffffL
else:
header_offset = zinfo.header_offset extra_data = zinfo.extra
if extra:
# Append a ZIP64 field to the extra's
extra_data = struct.pack(
'<HH' + 'Q'*len(extra),
1, 8*len(extra), *extra) + extra_data extract_version = max(45, zinfo.extract_version)
create_version = max(45, zinfo.create_version)
else:
extract_version = zinfo.extract_version
create_version = zinfo.create_version try:
filename, flag_bits = zinfo._encodeFilenameFlags()
centdir = struct.pack(structCentralDir,
stringCentralDir, create_version,
zinfo.create_system, extract_version, zinfo.reserved,
flag_bits, zinfo.compress_type, dostime, dosdate,
zinfo.CRC, compress_size, file_size,
len(filename), len(extra_data), len(zinfo.comment),
0, zinfo.internal_attr, zinfo.external_attr,
header_offset)
except DeprecationWarning:
print >>sys.stderr, (structCentralDir,
stringCentralDir, create_version,
zinfo.create_system, extract_version, zinfo.reserved,
zinfo.flag_bits, zinfo.compress_type, dostime, dosdate,
zinfo.CRC, compress_size, file_size,
len(zinfo.filename), len(extra_data), len(zinfo.comment),
0, zinfo.internal_attr, zinfo.external_attr,
header_offset)
raise
self.fp.write(centdir)
self.fp.write(filename)
self.fp.write(extra_data)
self.fp.write(zinfo.comment) pos2 = self.fp.tell()
# Write end-of-zip-archive record
centDirCount = len(self.filelist)
centDirSize = pos2 - pos1
centDirOffset = pos1
requires_zip64 = None
if centDirCount > ZIP_FILECOUNT_LIMIT:
requires_zip64 = "Files count"
elif centDirOffset > ZIP64_LIMIT:
requires_zip64 = "Central directory offset"
elif centDirSize > ZIP64_LIMIT:
requires_zip64 = "Central directory size"
if requires_zip64:
# Need to write the ZIP64 end-of-archive records
if not self._allowZip64:
raise LargeZipFile(requires_zip64 +
" would require ZIP64 extensions")
zip64endrec = struct.pack(
structEndArchive64, stringEndArchive64,
44, 45, 45, 0, 0, centDirCount, centDirCount,
centDirSize, centDirOffset)
self.fp.write(zip64endrec) zip64locrec = struct.pack(
structEndArchive64Locator,
stringEndArchive64Locator, 0, pos2, 1)
self.fp.write(zip64locrec)
centDirCount = min(centDirCount, 0xFFFF)
centDirSize = min(centDirSize, 0xFFFFFFFF)
centDirOffset = min(centDirOffset, 0xFFFFFFFF) endrec = struct.pack(structEndArchive, stringEndArchive,
0, 0, centDirCount, centDirCount,
centDirSize, centDirOffset, len(self._comment))
self.fp.write(endrec)
self.fp.write(self._comment)
self.fp.flush()
finally:
fp = self.fp
self.fp = None
if not self._filePassed:
fp.close()

ZipFile

 class TarFile(object):
"""The TarFile Class provides an interface to tar archives.
""" debug = 0 # May be set from 0 (no msgs) to 3 (all msgs) dereference = False # If true, add content of linked file to the
# tar file, else the link. ignore_zeros = False # If true, skips empty or invalid blocks and
# continues processing. errorlevel = 1 # If 0, fatal errors only appear in debug
# messages (if debug >= 0). If > 0, errors
# are passed to the caller as exceptions. format = DEFAULT_FORMAT # The format to use when creating an archive. encoding = ENCODING # Encoding for 8-bit character strings. errors = None # Error handler for unicode conversion. tarinfo = TarInfo # The default TarInfo class to use. fileobject = ExFileObject # The default ExFileObject class to use. def __init__(self, name=None, mode="r", fileobj=None, format=None,
tarinfo=None, dereference=None, ignore_zeros=None, encoding=None,
errors=None, pax_headers=None, debug=None, errorlevel=None):
"""Open an (uncompressed) tar archive `name'. `mode' is either 'r' to
read from an existing archive, 'a' to append data to an existing
file or 'w' to create a new file overwriting an existing one. `mode'
defaults to 'r'.
If `fileobj' is given, it is used for reading or writing data. If it
can be determined, `mode' is overridden by `fileobj's mode.
`fileobj' is not closed, when TarFile is closed.
"""
modes = {"r": "rb", "a": "r+b", "w": "wb"}
if mode not in modes:
raise ValueError("mode must be 'r', 'a' or 'w'")
self.mode = mode
self._mode = modes[mode] if not fileobj:
if self.mode == "a" and not os.path.exists(name):
# Create nonexistent files in append mode.
self.mode = "w"
self._mode = "wb"
fileobj = bltn_open(name, self._mode)
self._extfileobj = False
else:
if name is None and hasattr(fileobj, "name"):
name = fileobj.name
if hasattr(fileobj, "mode"):
self._mode = fileobj.mode
self._extfileobj = True
self.name = os.path.abspath(name) if name else None
self.fileobj = fileobj # Init attributes.
if format is not None:
self.format = format
if tarinfo is not None:
self.tarinfo = tarinfo
if dereference is not None:
self.dereference = dereference
if ignore_zeros is not None:
self.ignore_zeros = ignore_zeros
if encoding is not None:
self.encoding = encoding if errors is not None:
self.errors = errors
elif mode == "r":
self.errors = "utf-8"
else:
self.errors = "strict" if pax_headers is not None and self.format == PAX_FORMAT:
self.pax_headers = pax_headers
else:
self.pax_headers = {} if debug is not None:
self.debug = debug
if errorlevel is not None:
self.errorlevel = errorlevel # Init datastructures.
self.closed = False
self.members = [] # list of members as TarInfo objects
self._loaded = False # flag if all members have been read
self.offset = self.fileobj.tell()
# current position in the archive file
self.inodes = {} # dictionary caching the inodes of
# archive members already added try:
if self.mode == "r":
self.firstmember = None
self.firstmember = self.next() if self.mode == "a":
# Move to the end of the archive,
# before the first empty block.
while True:
self.fileobj.seek(self.offset)
try:
tarinfo = self.tarinfo.fromtarfile(self)
self.members.append(tarinfo)
except EOFHeaderError:
self.fileobj.seek(self.offset)
break
except HeaderError, e:
raise ReadError(str(e)) if self.mode in "aw":
self._loaded = True if self.pax_headers:
buf = self.tarinfo.create_pax_global_header(self.pax_headers.copy())
self.fileobj.write(buf)
self.offset += len(buf)
except:
if not self._extfileobj:
self.fileobj.close()
self.closed = True
raise def _getposix(self):
return self.format == USTAR_FORMAT
def _setposix(self, value):
import warnings
warnings.warn("use the format attribute instead", DeprecationWarning,
2)
if value:
self.format = USTAR_FORMAT
else:
self.format = GNU_FORMAT
posix = property(_getposix, _setposix) #--------------------------------------------------------------------------
# Below are the classmethods which act as alternate constructors to the
# TarFile class. The open() method is the only one that is needed for
# public use; it is the "super"-constructor and is able to select an
# adequate "sub"-constructor for a particular compression using the mapping
# from OPEN_METH.
#
# This concept allows one to subclass TarFile without losing the comfort of
# the super-constructor. A sub-constructor is registered and made available
# by adding it to the mapping in OPEN_METH. @classmethod
def open(cls, name=None, mode="r", fileobj=None, bufsize=RECORDSIZE, **kwargs):
"""Open a tar archive for reading, writing or appending. Return
an appropriate TarFile class. mode:
'r' or 'r:*' open for reading with transparent compression
'r:' open for reading exclusively uncompressed
'r:gz' open for reading with gzip compression
'r:bz2' open for reading with bzip2 compression
'a' or 'a:' open for appending, creating the file if necessary
'w' or 'w:' open for writing without compression
'w:gz' open for writing with gzip compression
'w:bz2' open for writing with bzip2 compression 'r|*' open a stream of tar blocks with transparent compression
'r|' open an uncompressed stream of tar blocks for reading
'r|gz' open a gzip compressed stream of tar blocks
'r|bz2' open a bzip2 compressed stream of tar blocks
'w|' open an uncompressed stream for writing
'w|gz' open a gzip compressed stream for writing
'w|bz2' open a bzip2 compressed stream for writing
""" if not name and not fileobj:
raise ValueError("nothing to open") if mode in ("r", "r:*"):
# Find out which *open() is appropriate for opening the file.
for comptype in cls.OPEN_METH:
func = getattr(cls, cls.OPEN_METH[comptype])
if fileobj is not None:
saved_pos = fileobj.tell()
try:
return func(name, "r", fileobj, **kwargs)
except (ReadError, CompressionError), e:
if fileobj is not None:
fileobj.seek(saved_pos)
continue
raise ReadError("file could not be opened successfully") elif ":" in mode:
filemode, comptype = mode.split(":", 1)
filemode = filemode or "r"
comptype = comptype or "tar" # Select the *open() function according to
# given compression.
if comptype in cls.OPEN_METH:
func = getattr(cls, cls.OPEN_METH[comptype])
else:
raise CompressionError("unknown compression type %r" % comptype)
return func(name, filemode, fileobj, **kwargs) elif "|" in mode:
filemode, comptype = mode.split("|", 1)
filemode = filemode or "r"
comptype = comptype or "tar" if filemode not in ("r", "w"):
raise ValueError("mode must be 'r' or 'w'") stream = _Stream(name, filemode, comptype, fileobj, bufsize)
try:
t = cls(name, filemode, stream, **kwargs)
except:
stream.close()
raise
t._extfileobj = False
return t elif mode in ("a", "w"):
return cls.taropen(name, mode, fileobj, **kwargs) raise ValueError("undiscernible mode") @classmethod
def taropen(cls, name, mode="r", fileobj=None, **kwargs):
"""Open uncompressed tar archive name for reading or writing.
"""
if mode not in ("r", "a", "w"):
raise ValueError("mode must be 'r', 'a' or 'w'")
return cls(name, mode, fileobj, **kwargs) @classmethod
def gzopen(cls, name, mode="r", fileobj=None, compresslevel=9, **kwargs):
"""Open gzip compressed tar archive name for reading or writing.
Appending is not allowed.
"""
if mode not in ("r", "w"):
raise ValueError("mode must be 'r' or 'w'") try:
import gzip
gzip.GzipFile
except (ImportError, AttributeError):
raise CompressionError("gzip module is not available") try:
fileobj = gzip.GzipFile(name, mode, compresslevel, fileobj)
except OSError:
if fileobj is not None and mode == 'r':
raise ReadError("not a gzip file")
raise try:
t = cls.taropen(name, mode, fileobj, **kwargs)
except IOError:
fileobj.close()
if mode == 'r':
raise ReadError("not a gzip file")
raise
except:
fileobj.close()
raise
t._extfileobj = False
return t @classmethod
def bz2open(cls, name, mode="r", fileobj=None, compresslevel=9, **kwargs):
"""Open bzip2 compressed tar archive name for reading or writing.
Appending is not allowed.
"""
if mode not in ("r", "w"):
raise ValueError("mode must be 'r' or 'w'.") try:
import bz2
except ImportError:
raise CompressionError("bz2 module is not available") if fileobj is not None:
fileobj = _BZ2Proxy(fileobj, mode)
else:
fileobj = bz2.BZ2File(name, mode, compresslevel=compresslevel) try:
t = cls.taropen(name, mode, fileobj, **kwargs)
except (IOError, EOFError):
fileobj.close()
if mode == 'r':
raise ReadError("not a bzip2 file")
raise
except:
fileobj.close()
raise
t._extfileobj = False
return t # All *open() methods are registered here.
OPEN_METH = {
"tar": "taropen", # uncompressed tar
"gz": "gzopen", # gzip compressed tar
"bz2": "bz2open" # bzip2 compressed tar
} #--------------------------------------------------------------------------
# The public methods which TarFile provides: def close(self):
"""Close the TarFile. In write-mode, two finishing zero blocks are
appended to the archive.
"""
if self.closed:
return if self.mode in "aw":
self.fileobj.write(NUL * (BLOCKSIZE * 2))
self.offset += (BLOCKSIZE * 2)
# fill up the end with zero-blocks
# (like option -b20 for tar does)
blocks, remainder = divmod(self.offset, RECORDSIZE)
if remainder > 0:
self.fileobj.write(NUL * (RECORDSIZE - remainder)) if not self._extfileobj:
self.fileobj.close()
self.closed = True def getmember(self, name):
"""Return a TarInfo object for member `name'. If `name' can not be
found in the archive, KeyError is raised. If a member occurs more
than once in the archive, its last occurrence is assumed to be the
most up-to-date version.
"""
tarinfo = self._getmember(name)
if tarinfo is None:
raise KeyError("filename %r not found" % name)
return tarinfo def getmembers(self):
"""Return the members of the archive as a list of TarInfo objects. The
list has the same order as the members in the archive.
"""
self._check()
if not self._loaded: # if we want to obtain a list of
self._load() # all members, we first have to
# scan the whole archive.
return self.members def getnames(self):
"""Return the members of the archive as a list of their names. It has
the same order as the list returned by getmembers().
"""
return [tarinfo.name for tarinfo in self.getmembers()] def gettarinfo(self, name=None, arcname=None, fileobj=None):
"""Create a TarInfo object for either the file `name' or the file
object `fileobj' (using os.fstat on its file descriptor). You can
modify some of the TarInfo's attributes before you add it using
addfile(). If given, `arcname' specifies an alternative name for the
file in the archive.
"""
self._check("aw") # When fileobj is given, replace name by
# fileobj's real name.
if fileobj is not None:
name = fileobj.name # Building the name of the member in the archive.
# Backward slashes are converted to forward slashes,
# Absolute paths are turned to relative paths.
if arcname is None:
arcname = name
drv, arcname = os.path.splitdrive(arcname)
arcname = arcname.replace(os.sep, "/")
arcname = arcname.lstrip("/") # Now, fill the TarInfo object with
# information specific for the file.
tarinfo = self.tarinfo()
tarinfo.tarfile = self # Use os.stat or os.lstat, depending on platform
# and if symlinks shall be resolved.
if fileobj is None:
if hasattr(os, "lstat") and not self.dereference:
statres = os.lstat(name)
else:
statres = os.stat(name)
else:
statres = os.fstat(fileobj.fileno())
linkname = "" stmd = statres.st_mode
if stat.S_ISREG(stmd):
inode = (statres.st_ino, statres.st_dev)
if not self.dereference and statres.st_nlink > 1 and \
inode in self.inodes and arcname != self.inodes[inode]:
# Is it a hardlink to an already
# archived file?
type = LNKTYPE
linkname = self.inodes[inode]
else:
# The inode is added only if its valid.
# For win32 it is always 0.
type = REGTYPE
if inode[0]:
self.inodes[inode] = arcname
elif stat.S_ISDIR(stmd):
type = DIRTYPE
elif stat.S_ISFIFO(stmd):
type = FIFOTYPE
elif stat.S_ISLNK(stmd):
type = SYMTYPE
linkname = os.readlink(name)
elif stat.S_ISCHR(stmd):
type = CHRTYPE
elif stat.S_ISBLK(stmd):
type = BLKTYPE
else:
return None # Fill the TarInfo object with all
# information we can get.
tarinfo.name = arcname
tarinfo.mode = stmd
tarinfo.uid = statres.st_uid
tarinfo.gid = statres.st_gid
if type == REGTYPE:
tarinfo.size = statres.st_size
else:
tarinfo.size = 0L
tarinfo.mtime = statres.st_mtime
tarinfo.type = type
tarinfo.linkname = linkname
if pwd:
try:
tarinfo.uname = pwd.getpwuid(tarinfo.uid)[0]
except KeyError:
pass
if grp:
try:
tarinfo.gname = grp.getgrgid(tarinfo.gid)[0]
except KeyError:
pass if type in (CHRTYPE, BLKTYPE):
if hasattr(os, "major") and hasattr(os, "minor"):
tarinfo.devmajor = os.major(statres.st_rdev)
tarinfo.devminor = os.minor(statres.st_rdev)
return tarinfo def list(self, verbose=True):
"""Print a table of contents to sys.stdout. If `verbose' is False, only
the names of the members are printed. If it is True, an `ls -l'-like
output is produced.
"""
self._check() for tarinfo in self:
if verbose:
print filemode(tarinfo.mode),
print "%s/%s" % (tarinfo.uname or tarinfo.uid,
tarinfo.gname or tarinfo.gid),
if tarinfo.ischr() or tarinfo.isblk():
print "%10s" % ("%d,%d" \
% (tarinfo.devmajor, tarinfo.devminor)),
else:
print "%10d" % tarinfo.size,
print "%d-%02d-%02d %02d:%02d:%02d" \
% time.localtime(tarinfo.mtime)[:6], print tarinfo.name + ("/" if tarinfo.isdir() else ""), if verbose:
if tarinfo.issym():
print "->", tarinfo.linkname,
if tarinfo.islnk():
print "link to", tarinfo.linkname,
print def add(self, name, arcname=None, recursive=True, exclude=None, filter=None):
"""Add the file `name' to the archive. `name' may be any type of file
(directory, fifo, symbolic link, etc.). If given, `arcname'
specifies an alternative name for the file in the archive.
Directories are added recursively by default. This can be avoided by
setting `recursive' to False. `exclude' is a function that should
return True for each filename to be excluded. `filter' is a function
that expects a TarInfo object argument and returns the changed
TarInfo object, if it returns None the TarInfo object will be
excluded from the archive.
"""
self._check("aw") if arcname is None:
arcname = name # Exclude pathnames.
if exclude is not None:
import warnings
warnings.warn("use the filter argument instead",
DeprecationWarning, 2)
if exclude(name):
self._dbg(2, "tarfile: Excluded %r" % name)
return # Skip if somebody tries to archive the archive...
if self.name is not None and os.path.abspath(name) == self.name:
self._dbg(2, "tarfile: Skipped %r" % name)
return self._dbg(1, name) # Create a TarInfo object from the file.
tarinfo = self.gettarinfo(name, arcname) if tarinfo is None:
self._dbg(1, "tarfile: Unsupported type %r" % name)
return # Change or exclude the TarInfo object.
if filter is not None:
tarinfo = filter(tarinfo)
if tarinfo is None:
self._dbg(2, "tarfile: Excluded %r" % name)
return # Append the tar header and data to the archive.
if tarinfo.isreg():
with bltn_open(name, "rb") as f:
self.addfile(tarinfo, f) elif tarinfo.isdir():
self.addfile(tarinfo)
if recursive:
for f in os.listdir(name):
self.add(os.path.join(name, f), os.path.join(arcname, f),
recursive, exclude, filter) else:
self.addfile(tarinfo) def addfile(self, tarinfo, fileobj=None):
"""Add the TarInfo object `tarinfo' to the archive. If `fileobj' is
given, tarinfo.size bytes are read from it and added to the archive.
You can create TarInfo objects using gettarinfo().
On Windows platforms, `fileobj' should always be opened with mode
'rb' to avoid irritation about the file size.
"""
self._check("aw") tarinfo = copy.copy(tarinfo) buf = tarinfo.tobuf(self.format, self.encoding, self.errors)
self.fileobj.write(buf)
self.offset += len(buf) # If there's data to follow, append it.
if fileobj is not None:
copyfileobj(fileobj, self.fileobj, tarinfo.size)
blocks, remainder = divmod(tarinfo.size, BLOCKSIZE)
if remainder > 0:
self.fileobj.write(NUL * (BLOCKSIZE - remainder))
blocks += 1
self.offset += blocks * BLOCKSIZE self.members.append(tarinfo) def extractall(self, path=".", members=None):
"""Extract all members from the archive to the current working
directory and set owner, modification time and permissions on
directories afterwards. `path' specifies a different directory
to extract to. `members' is optional and must be a subset of the
list returned by getmembers().
"""
directories = [] if members is None:
members = self for tarinfo in members:
if tarinfo.isdir():
# Extract directories with a safe mode.
directories.append(tarinfo)
tarinfo = copy.copy(tarinfo)
tarinfo.mode = 0700
self.extract(tarinfo, path) # Reverse sort directories.
directories.sort(key=operator.attrgetter('name'))
directories.reverse() # Set correct owner, mtime and filemode on directories.
for tarinfo in directories:
dirpath = os.path.join(path, tarinfo.name)
try:
self.chown(tarinfo, dirpath)
self.utime(tarinfo, dirpath)
self.chmod(tarinfo, dirpath)
except ExtractError, e:
if self.errorlevel > 1:
raise
else:
self._dbg(1, "tarfile: %s" % e) def extract(self, member, path=""):
"""Extract a member from the archive to the current working directory,
using its full name. Its file information is extracted as accurately
as possible. `member' may be a filename or a TarInfo object. You can
specify a different directory using `path'.
"""
self._check("r") if isinstance(member, basestring):
tarinfo = self.getmember(member)
else:
tarinfo = member # Prepare the link target for makelink().
if tarinfo.islnk():
tarinfo._link_target = os.path.join(path, tarinfo.linkname) try:
self._extract_member(tarinfo, os.path.join(path, tarinfo.name))
except EnvironmentError, e:
if self.errorlevel > 0:
raise
else:
if e.filename is None:
self._dbg(1, "tarfile: %s" % e.strerror)
else:
self._dbg(1, "tarfile: %s %r" % (e.strerror, e.filename))
except ExtractError, e:
if self.errorlevel > 1:
raise
else:
self._dbg(1, "tarfile: %s" % e) def extractfile(self, member):
"""Extract a member from the archive as a file object. `member' may be
a filename or a TarInfo object. If `member' is a regular file, a
file-like object is returned. If `member' is a link, a file-like
object is constructed from the link's target. If `member' is none of
the above, None is returned.
The file-like object is read-only and provides the following
methods: read(), readline(), readlines(), seek() and tell()
"""
self._check("r") if isinstance(member, basestring):
tarinfo = self.getmember(member)
else:
tarinfo = member if tarinfo.isreg():
return self.fileobject(self, tarinfo) elif tarinfo.type not in SUPPORTED_TYPES:
# If a member's type is unknown, it is treated as a
# regular file.
return self.fileobject(self, tarinfo) elif tarinfo.islnk() or tarinfo.issym():
if isinstance(self.fileobj, _Stream):
# A small but ugly workaround for the case that someone tries
# to extract a (sym)link as a file-object from a non-seekable
# stream of tar blocks.
raise StreamError("cannot extract (sym)link as file object")
else:
# A (sym)link's file object is its target's file object.
return self.extractfile(self._find_link_target(tarinfo))
else:
# If there's no data associated with the member (directory, chrdev,
# blkdev, etc.), return None instead of a file object.
return None def _extract_member(self, tarinfo, targetpath):
"""Extract the TarInfo object tarinfo to a physical
file called targetpath.
"""
# Fetch the TarInfo object for the given name
# and build the destination pathname, replacing
# forward slashes to platform specific separators.
targetpath = targetpath.rstrip("/")
targetpath = targetpath.replace("/", os.sep) # Create all upper directories.
upperdirs = os.path.dirname(targetpath)
if upperdirs and not os.path.exists(upperdirs):
# Create directories that are not part of the archive with
# default permissions.
os.makedirs(upperdirs) if tarinfo.islnk() or tarinfo.issym():
self._dbg(1, "%s -> %s" % (tarinfo.name, tarinfo.linkname))
else:
self._dbg(1, tarinfo.name) if tarinfo.isreg():
self.makefile(tarinfo, targetpath)
elif tarinfo.isdir():
self.makedir(tarinfo, targetpath)
elif tarinfo.isfifo():
self.makefifo(tarinfo, targetpath)
elif tarinfo.ischr() or tarinfo.isblk():
self.makedev(tarinfo, targetpath)
elif tarinfo.islnk() or tarinfo.issym():
self.makelink(tarinfo, targetpath)
elif tarinfo.type not in SUPPORTED_TYPES:
self.makeunknown(tarinfo, targetpath)
else:
self.makefile(tarinfo, targetpath) self.chown(tarinfo, targetpath)
if not tarinfo.issym():
self.chmod(tarinfo, targetpath)
self.utime(tarinfo, targetpath) #--------------------------------------------------------------------------
# Below are the different file methods. They are called via
# _extract_member() when extract() is called. They can be replaced in a
# subclass to implement other functionality. def makedir(self, tarinfo, targetpath):
"""Make a directory called targetpath.
"""
try:
# Use a safe mode for the directory, the real mode is set
# later in _extract_member().
os.mkdir(targetpath, 0700)
except EnvironmentError, e:
if e.errno != errno.EEXIST:
raise def makefile(self, tarinfo, targetpath):
"""Make a file called targetpath.
"""
source = self.extractfile(tarinfo)
try:
with bltn_open(targetpath, "wb") as target:
copyfileobj(source, target)
finally:
source.close() def makeunknown(self, tarinfo, targetpath):
"""Make a file from a TarInfo object with an unknown type
at targetpath.
"""
self.makefile(tarinfo, targetpath)
self._dbg(1, "tarfile: Unknown file type %r, " \
"extracted as regular file." % tarinfo.type) def makefifo(self, tarinfo, targetpath):
"""Make a fifo called targetpath.
"""
if hasattr(os, "mkfifo"):
os.mkfifo(targetpath)
else:
raise ExtractError("fifo not supported by system") def makedev(self, tarinfo, targetpath):
"""Make a character or block device called targetpath.
"""
if not hasattr(os, "mknod") or not hasattr(os, "makedev"):
raise ExtractError("special devices not supported by system") mode = tarinfo.mode
if tarinfo.isblk():
mode |= stat.S_IFBLK
else:
mode |= stat.S_IFCHR os.mknod(targetpath, mode,
os.makedev(tarinfo.devmajor, tarinfo.devminor)) def makelink(self, tarinfo, targetpath):
"""Make a (symbolic) link called targetpath. If it cannot be created
(platform limitation), we try to make a copy of the referenced file
instead of a link.
"""
if hasattr(os, "symlink") and hasattr(os, "link"):
# For systems that support symbolic and hard links.
if tarinfo.issym():
if os.path.lexists(targetpath):
os.unlink(targetpath)
os.symlink(tarinfo.linkname, targetpath)
else:
# See extract().
if os.path.exists(tarinfo._link_target):
if os.path.lexists(targetpath):
os.unlink(targetpath)
os.link(tarinfo._link_target, targetpath)
else:
self._extract_member(self._find_link_target(tarinfo), targetpath)
else:
try:
self._extract_member(self._find_link_target(tarinfo), targetpath)
except KeyError:
raise ExtractError("unable to resolve link inside archive") def chown(self, tarinfo, targetpath):
"""Set owner of targetpath according to tarinfo.
"""
if pwd and hasattr(os, "geteuid") and os.geteuid() == 0:
# We have to be root to do so.
try:
g = grp.getgrnam(tarinfo.gname)[2]
except KeyError:
g = tarinfo.gid
try:
u = pwd.getpwnam(tarinfo.uname)[2]
except KeyError:
u = tarinfo.uid
try:
if tarinfo.issym() and hasattr(os, "lchown"):
os.lchown(targetpath, u, g)
else:
if sys.platform != "os2emx":
os.chown(targetpath, u, g)
except EnvironmentError, e:
raise ExtractError("could not change owner") def chmod(self, tarinfo, targetpath):
"""Set file permissions of targetpath according to tarinfo.
"""
if hasattr(os, 'chmod'):
try:
os.chmod(targetpath, tarinfo.mode)
except EnvironmentError, e:
raise ExtractError("could not change mode") def utime(self, tarinfo, targetpath):
"""Set modification time of targetpath according to tarinfo.
"""
if not hasattr(os, 'utime'):
return
try:
os.utime(targetpath, (tarinfo.mtime, tarinfo.mtime))
except EnvironmentError, e:
raise ExtractError("could not change modification time") #--------------------------------------------------------------------------
def next(self):
"""Return the next member of the archive as a TarInfo object, when
TarFile is opened for reading. Return None if there is no more
available.
"""
self._check("ra")
if self.firstmember is not None:
m = self.firstmember
self.firstmember = None
return m # Read the next block.
self.fileobj.seek(self.offset)
tarinfo = None
while True:
try:
tarinfo = self.tarinfo.fromtarfile(self)
except EOFHeaderError, e:
if self.ignore_zeros:
self._dbg(2, "0x%X: %s" % (self.offset, e))
self.offset += BLOCKSIZE
continue
except InvalidHeaderError, e:
if self.ignore_zeros:
self._dbg(2, "0x%X: %s" % (self.offset, e))
self.offset += BLOCKSIZE
continue
elif self.offset == 0:
raise ReadError(str(e))
except EmptyHeaderError:
if self.offset == 0:
raise ReadError("empty file")
except TruncatedHeaderError, e:
if self.offset == 0:
raise ReadError(str(e))
except SubsequentHeaderError, e:
raise ReadError(str(e))
break if tarinfo is not None:
self.members.append(tarinfo)
else:
self._loaded = True return tarinfo #--------------------------------------------------------------------------
# Little helper methods: def _getmember(self, name, tarinfo=None, normalize=False):
"""Find an archive member by name from bottom to top.
If tarinfo is given, it is used as the starting point.
"""
# Ensure that all members have been loaded.
members = self.getmembers() # Limit the member search list up to tarinfo.
if tarinfo is not None:
members = members[:members.index(tarinfo)] if normalize:
name = os.path.normpath(name) for member in reversed(members):
if normalize:
member_name = os.path.normpath(member.name)
else:
member_name = member.name if name == member_name:
return member def _load(self):
"""Read through the entire archive file and look for readable
members.
"""
while True:
tarinfo = self.next()
if tarinfo is None:
break
self._loaded = True def _check(self, mode=None):
"""Check if TarFile is still open, and if the operation's mode
corresponds to TarFile's mode.
"""
if self.closed:
raise IOError("%s is closed" % self.__class__.__name__)
if mode is not None and self.mode not in mode:
raise IOError("bad operation for mode %r" % self.mode) def _find_link_target(self, tarinfo):
"""Find the target member of a symlink or hardlink member in the
archive.
"""
if tarinfo.issym():
# Always search the entire archive.
linkname = "/".join(filter(None, (os.path.dirname(tarinfo.name), tarinfo.linkname)))
limit = None
else:
# Search the archive before the link, because a hard link is
# just a reference to an already archived file.
linkname = tarinfo.linkname
limit = tarinfo member = self._getmember(linkname, tarinfo=limit, normalize=True)
if member is None:
raise KeyError("linkname %r not found" % linkname)
return member def __iter__(self):
"""Provide an iterator object.
"""
if self._loaded:
return iter(self.members)
else:
return TarIter(self) def _dbg(self, level, msg):
"""Write debugging output to sys.stderr.
"""
if level <= self.debug:
print >> sys.stderr, msg def __enter__(self):
self._check()
return self def __exit__(self, type, value, traceback):
if type is None:
self.close()
else:
# An exception occurred. We must not call close() because
# it would try to write end-of-archive blocks and padding.
if not self._extfileobj:
self.fileobj.close()
self.closed = True
# class TarFile

TarFil

shelve 模块

shelve模块是一个简单的k,v将内存数据通过文件持久化的模块,可以持久化任何pickle可支持的python数据格式

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
import shelve
 
= shelve.open('shelve_test'#打开一个文件
 
class Test(object):
    def __init__(self,n):
        self.n = n
 
 
= Test(123
t2 = Test(123334)
 
name = ["alex","rain","test"]
d["test"= name #持久化列表
d["t1"= t      #持久化类
d["t2"= t2
 
d.close()

xml处理模块

xml是实现不同语言或程序之间进行数据交换的协议,跟json差不多,但json使用起来更简单,不过,古时候,在json还没诞生的黑暗年代,大家只能选择用xml呀,至今很多传统公司如金融行业的很多系统的接口还主要是xml。

xml的格式如下,就是通过<>节点来区别数据结构的:

 <?xml version="1.0"?>
<data>
<country name="Liechtenstein">
<rank updated="yes">2</rank>
<year>2008</year>
<gdppc>141100</gdppc>
<neighbor name="Austria" direction="E"/>
<neighbor name="Switzerland" direction="W"/>
</country>
<country name="Singapore">
<rank updated="yes">5</rank>
<year>2011</year>
<gdppc>59900</gdppc>
<neighbor name="Malaysia" direction="N"/>
</country>
<country name="Panama">
<rank updated="yes">69</rank>
<year>2011</year>
<gdppc>13600</gdppc>
<neighbor name="Costa Rica" direction="W"/>
<neighbor name="Colombia" direction="E"/>
</country>
</data>

xml协议在各个语言里的都 是支持的,在python中可以用以下模块操作xml   

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
import xml.etree.ElementTree as ET
 
tree = ET.parse("xmltest.xml")
root = tree.getroot()
print(root.tag)
 
#遍历xml文档
for child in root:
    print(child.tag, child.attrib)
    for in child:
        print(i.tag,i.text)
 
#只遍历year 节点
for node in root.iter('year'):
    print(node.tag,node.text)

修改和删除xml文档内容

 import xml.etree.ElementTree as ET

 tree = ET.parse("xmltest.xml")
root = tree.getroot() #修改
for node in root.iter('year'):
new_year = int(node.text) + 1
node.text = str(new_year)
node.set("updated","yes") tree.write("xmltest.xml") #删除node
for country in root.findall('country'):
rank = int(country.find('rank').text)
if rank > 50:
root.remove(country) tree.write('output.xml')

自己创建xml文档

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
import xml.etree.ElementTree as ET
 
 
new_xml = ET.Element("namelist")
name = ET.SubElement(new_xml,"name",attrib={"enrolled":"yes"})
age = ET.SubElement(name,"age",attrib={"checked":"no"})
sex = ET.SubElement(name,"sex")
sex.text = '33'
name2 = ET.SubElement(new_xml,"name",attrib={"enrolled":"no"})
age = ET.SubElement(name2,"age")
age.text = '19'
 
et = ET.ElementTree(new_xml) #生成文档对象
et.write("test.xml", encoding="utf-8",xml_declaration=True)
 
ET.dump(new_xml) #打印生成的格式

ConfigParser模块

用于生成和修改常见配置文档,当前模块的名称在 python 3.x 版本中变更为 configparser。

来看一个好多软件的常见文档格式如下

1
2
3
4
5
6
7
8
9
10
11
12
[DEFAULT]
ServerAliveInterval = 45
Compression = yes
CompressionLevel = 9
ForwardX11 = yes
 
[bitbucket.org]
User = hg
 
[topsecret.server.com]
Port = 50022
ForwardX11 = no

如果想用python生成一个这样的文档怎么做呢?

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
import configparser
 
config = configparser.ConfigParser()
config["DEFAULT"= {'ServerAliveInterval''45',
                      'Compression''yes',
                     'CompressionLevel''9'}
 
config['bitbucket.org'= {}
config['bitbucket.org']['User'= 'hg'
config['topsecret.server.com'= {}
topsecret = config['topsecret.server.com']
topsecret['Host Port'= '50022'     # mutates the parser
topsecret['ForwardX11'= 'no'  # same here
config['DEFAULT']['ForwardX11'= 'yes'
with open('example.ini''w') as configfile:
   config.write(configfile)

  

写完了还可以再读出来哈。

configparser增

 >>> import configparser
>>> config = configparser.ConfigParser()
>>> config.sections()
[]
>>> config.read('example.ini')
['example.ini']
>>> config.sections()
['bitbucket.org', 'topsecret.server.com']
>>> 'bitbucket.org' in config
True
>>> 'bytebong.com' in config
False
>>> config['bitbucket.org']['User']
'hg'
>>> config['DEFAULT']['Compression']
'yes'
>>> topsecret = config['topsecret.server.com']
>>> topsecret['ForwardX11']
'no'
>>> topsecret['Port']
''
>>> for key in config['bitbucket.org']: print(key)
...
user
compressionlevel
serveraliveinterval
compression
forwardx11
>>> config['bitbucket.org']['ForwardX11']
'yes'

删改查语法

 [section1]
k1 = v1
k2:v2 [section2]
k1 = v1 import ConfigParser config = ConfigParser.ConfigParser()
config.read('i.cfg') # ########## 读 ##########
#secs = config.sections()
#print secs
#options = config.options('group2')
#print options #item_list = config.items('group2')
#print item_list #val = config.get('group1','key')
#val = config.getint('group1','key') # ########## 改写 ##########
#sec = config.remove_section('group1')
#config.write(open('i.cfg', "w")) #sec = config.has_section('wupeiqi')
#sec = config.add_section('wupeiqi')
#config.write(open('i.cfg', "w")) #config.set('group2','k1',11111)
#config.write(open('i.cfg', "w")) #config.remove_option('group2','age')
#config.write(open('i.cfg', "w"))

hashlib模块  

用于加密相关的操作,3.x里代替了md5模块和sha模块,主要提供 SHA1, SHA224, SHA256, SHA384, SHA512 ,MD5 算法

 import hashlib

 m = hashlib.md5()
m.update(b"Hello")
m.update(b"It's me")
print(m.digest())
m.update(b"It's been a long time since last time we ...") print(m.digest()) #2进制格式hash
print(len(m.hexdigest())) #16进制格式hash
'''
def digest(self, *args, **kwargs): # real signature unknown
""" Return the digest value as a string of binary data. """
pass def hexdigest(self, *args, **kwargs): # real signature unknown
""" Return the digest value as a string of hexadecimal digits. """
pass '''
import hashlib # ######## md5 ######## hash = hashlib.md5()
hash.update('admin')
print(hash.hexdigest()) # ######## sha1 ######## hash = hashlib.sha1()
hash.update('admin')
print(hash.hexdigest()) # ######## sha256 ######## hash = hashlib.sha256()
hash.update('admin')
print(hash.hexdigest()) # ######## sha384 ######## hash = hashlib.sha384()
hash.update('admin')
print(hash.hexdigest()) # ######## sha512 ######## hash = hashlib.sha512()
hash.update('admin')
print(hash.hexdigest())

还不够吊?python 还有一个 hmac 模块,它内部对我们创建 key 和 内容 再进行处理然后再加密

1
2
3
4
import hmac
= hmac.new('wueiqi')
h.update('hellowo')
print h.hexdigest()

更多关于md5,sha1,sha256等介绍的文章看这里https://www.tbs-certificates.co.uk/FAQ/en/sha256.html

Subprocess模块 

The subprocess module allows you to spawn new processes, connect to their input/output/error pipes, and obtain their return codes. This module intends to replace several older modules and functions:

os.system
os.spawn*

The recommended approach to invoking subprocesses is to use the run() function for all use cases it can handle. For more advanced use cases, the underlying Popen interface can be used directly.

The run() function was added in Python 3.5; if you need to retain compatibility with older versions, see the Older high-level API section.

subprocess.run(args*stdin=Noneinput=Nonestdout=Nonestderr=Noneshell=Falsetimeout=Nonecheck=False)

Run the command described by args. Wait for command to complete, then return a CompletedProcess instance.

The arguments shown above are merely the most common ones, described below in Frequently Used Arguments (hence the use of keyword-only notation in the abbreviated signature). The full function signature is largely the same as that of the Popen constructor - apart from timeoutinput and check, all the arguments to this function are passed through to that interface.

This does not capture stdout or stderr by default. To do so, pass PIPE for the stdout and/or stderr arguments.

The timeout argument is passed to Popen.communicate(). If the timeout expires, the child process will be killed and waited for. The TimeoutExpired exception will be re-raised after the child process has terminated.

The input argument is passed to Popen.communicate() and thus to the subprocess’s stdin. If used it must be a byte sequence, or a string if universal_newlines=True. When used, the internal Popen object is automatically created withstdin=PIPE, and the stdin argument may not be used as well.

If check is True, and the process exits with a non-zero exit code, a CalledProcessError exception will be raised. Attributes of that exception hold the arguments, the exit code, and stdout and stderr if they were captured.

常用subprocess方法示例

#执行命令,返回命令执行状态 , 0 or 非0
>>> retcode = subprocess.call(["ls", "-l"])

#执行命令,如果命令结果为0,就正常返回,否则抛异常
>>> subprocess.check_call(["ls", "-l"])
0

#接收字符串格式命令,返回元组形式,第1个元素是执行状态,第2个是命令结果 
>>> subprocess.getstatusoutput('ls /bin/ls')
(0, '/bin/ls')

#接收字符串格式命令,并返回结果
>>> subprocess.getoutput('ls /bin/ls')
'/bin/ls'

#执行命令,并返回结果,注意是返回结果,不是打印,下例结果返回给res
>>> res=subprocess.check_output(['ls','-l'])
>>> res
b'total 0\ndrwxr-xr-x 12 alex staff 408 Nov 2 11:05 OldBoyCRM\n'

#上面那些方法,底层都是封装的subprocess.Popen
poll()
Check if child process has terminated. Returns returncode

wait()
Wait for child process to terminate. Returns returncode attribute.

terminate() 杀掉所启动进程
communicate() 等待任务结束

stdin 标准输入

stdout 标准输出

stderr 标准错误

pid
The process ID of the child process.

#例子
>>> p = subprocess.Popen("df -h|grep disk",stdin=subprocess.PIPE,stdout=subprocess.PIPE,shell=True)
>>> p.stdout.read()
b'/dev/disk1 465Gi 64Gi 400Gi 14% 16901472 104938142 14% /\n'

1
2
3
4
5
6
7
8
9
10
11
>>> subprocess.run(["ls""-l"])  # doesn't capture output
CompletedProcess(args=['ls''-l'], returncode=0)
 
>>> subprocess.run("exit 1", shell=True, check=True)
Traceback (most recent call last):
  ...
subprocess.CalledProcessError: Command 'exit 1' returned non-zero exit status 1
 
>>> subprocess.run(["ls""-l""/dev/null"], stdout=subprocess.PIPE)
CompletedProcess(args=['ls''-l''/dev/null'], returncode=0,
stdout=b'crw-rw-rw- 1 root root 1, 3 Jan 23 16:23 /dev/null\n')

调用subprocess.run(...)是推荐的常用方法,在大多数情况下能满足需求,但如果你可能需要进行一些复杂的与系统的交互的话,你还可以用subprocess.Popen(),语法如下:

1
2
= subprocess.Popen("find / -size +1000000 -exec ls -shl {} \;",shell=True,stdout=subprocess.PIPE)
print(p.stdout.read())

可用参数:

  • args:shell命令,可以是字符串或者序列类型(如:list,元组)
  • bufsize:指定缓冲。0 无缓冲,1 行缓冲,其他 缓冲区大小,负值 系统缓冲
  • stdin, stdout, stderr:分别表示程序的标准输入、输出、错误句柄
  • preexec_fn:只在Unix平台下有效,用于指定一个可执行对象(callable object),它将在子进程运行之前被调用
  • close_sfs:在windows平台下,如果close_fds被设置为True,则新创建的子进程将不会继承父进程的输入、输出、错误管道。
    所以不能将close_fds设置为True同时重定向子进程的标准输入、输出与错误(stdin, stdout, stderr)。
  • shell:同上
  • cwd:用于设置子进程的当前目录
  • env:用于指定子进程的环境变量。如果env = None,子进程的环境变量将从父进程中继承。
  • universal_newlines:不同系统的换行符不同,True -> 同意使用 \n
  • startupinfo与createionflags只在windows下有效
    将被传递给底层的CreateProcess()函数,用于设置子进程的一些属性,如:主窗口的外观,进程的优先级等等

终端输入的命令分为两种:

  • 输入即可得到输出,如:ifconfig
  • 输入进行某环境,依赖再输入,如:python

需要交互的命令示例

1
2
3
4
5
6
7
8
9
10
import subprocess
 
obj = subprocess.Popen(["python"], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
obj.stdin.write('print 1 \n ')
obj.stdin.write('print 2 \n ')
obj.stdin.write('print 3 \n ')
obj.stdin.write('print 4 \n ')
 
out_error_list = obj.communicate(timeout=10)
print out_error_list

subprocess实现sudo 自动输入密码

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
import subprocess
 
def mypass():
    mypass = '123' #or get the password from anywhere
    return mypass
 
echo = subprocess.Popen(['echo',mypass()],
                        stdout=subprocess.PIPE,
                        )
 
sudo = subprocess.Popen(['sudo','-S','iptables','-L'],
                        stdin=echo.stdout,
                        stdout=subprocess.PIPE,
                        )
 
end_of_pipe = sudo.stdout
 
print "Password ok \n Iptables Chains %s" % end_of_pipe.read()

  

logging模块  

很多程序都有记录日志的需求,并且日志中包含的信息即有正常的程序访问日志,还可能有错误、警告等信息输出,python的logging模块提供了标准的日志接口,你可以通过它存储各种格式的日志,logging的日志可以分为 debug()info()warning()error() and critical() 5个级别,下面我们看一下怎么用。

最简单用法

1
2
3
4
5
6
7
8
import logging
 
logging.warning("user [alex] attempted wrong password more than 3 times")
logging.critical("server is down")
 
#输出
WARNING:root:user [alex] attempted wrong password more than 3 times
CRITICAL:root:server is down

看一下这几个日志级别分别代表什么意思

Level When it’s used
DEBUG Detailed information, typically of interest only when diagnosing problems.
INFO Confirmation that things are working as expected.
WARNING An indication that something unexpected happened, or indicative of some problem in the near future (e.g. ‘disk space low’). The software is still working as expected.
ERROR Due to a more serious problem, the software has not been able to perform some function.
CRITICAL A serious error, indicating that the program itself may be unable to continue running.

  

如果想把日志写到文件里,也很简单

1
2
3
4
5
6
import logging
 
logging.basicConfig(filename='example.log',level=logging.INFO)
logging.debug('This message should go to the log file')
logging.info('So should this')
logging.warning('And this, too')

其中下面这句中的level=loggin.INFO意思是,把日志纪录级别设置为INFO,也就是说,只有比日志是INFO或比INFO级别更高的日志才会被纪录到文件里,在这个例子, 第一条日志是不会被纪录的,如果希望纪录debug的日志,那把日志级别改成DEBUG就行了。

1
logging.basicConfig(filename='example.log',level=logging.INFO)

感觉上面的日志格式忘记加上时间啦,日志不知道时间怎么行呢,下面就来加上!

1
2
3
4
5
6
import logging
logging.basicConfig(format='%(asctime)s %(message)s', datefmt='%m/%d/%Y %I:%M:%S %p')
logging.warning('is when this event was logged.')
 
#输出
12/12/2010 11:46:36 AM is when this event was logged.

日志格式

%(name)s

Logger的名字

%(levelno)s

数字形式的日志级别

%(levelname)s

文本形式的日志级别

%(pathname)s

调用日志输出函数的模块的完整路径名,可能没有

%(filename)s

调用日志输出函数的模块的文件名

%(module)s

调用日志输出函数的模块名

%(funcName)s

调用日志输出函数的函数名

%(lineno)d

调用日志输出函数的语句所在的代码行

%(created)f

当前时间,用UNIX标准的表示时间的浮 点数表示

%(relativeCreated)d

输出日志信息时的,自Logger创建以 来的毫秒数

%(asctime)s

字符串形式的当前时间。默认格式是 “2003-07-08 16:49:45,896”。逗号后面的是毫秒

%(thread)d

线程ID。可能没有

%(threadName)s

线程名。可能没有

%(process)d

进程ID。可能没有

%(message)s

用户输出的消息

  

如果想同时把log打印在屏幕和文件日志里,就需要了解一点复杂的知识 了

Python 使用logging模块记录日志涉及四个主要类,使用官方文档中的概括最为合适:

logger提供了应用程序可以直接使用的接口;

handler将(logger创建的)日志记录发送到合适的目的输出;

filter提供了细度设备来决定输出哪条日志记录;

formatter决定日志记录的最终输出格式。

logger
每个程序在输出信息之前都要获得一个Logger。Logger通常对应了程序的模块名,比如聊天工具的图形界面模块可以这样获得它的Logger:
LOG=logging.getLogger(”chat.gui”)
而核心模块可以这样:
LOG=logging.getLogger(”chat.kernel”)

Logger.setLevel(lel):指定最低的日志级别,低于lel的级别将被忽略。debug是最低的内置级别,critical为最高
Logger.addFilter(filt)、Logger.removeFilter(filt):添加或删除指定的filter
Logger.addHandler(hdlr)、Logger.removeHandler(hdlr):增加或删除指定的handler
Logger.debug()、Logger.info()、Logger.warning()、Logger.error()、Logger.critical():可以设置的日志级别

handler

handler对象负责发送相关的信息到指定目的地。Python的日志系统有多种Handler可以使用。有些Handler可以把信息输出到控制台,有些Logger可以把信息输出到文件,还有些 Handler可以把信息发送到网络上。如果觉得不够用,还可以编写自己的Handler。可以通过addHandler()方法添加多个多handler
Handler.setLevel(lel):指定被处理的信息级别,低于lel级别的信息将被忽略
Handler.setFormatter():给这个handler选择一个格式
Handler.addFilter(filt)、Handler.removeFilter(filt):新增或删除一个filter对象

每个Logger可以附加多个Handler。接下来我们就来介绍一些常用的Handler:
1) logging.StreamHandler
使用这个Handler可以向类似与sys.stdout或者sys.stderr的任何文件对象(file object)输出信息。它的构造函数是:
StreamHandler([strm])
其中strm参数是一个文件对象。默认是sys.stderr

2) logging.FileHandler
和StreamHandler类似,用于向一个文件输出日志信息。不过FileHandler会帮你打开这个文件。它的构造函数是:
FileHandler(filename[,mode])
filename是文件名,必须指定一个文件名。
mode是文件的打开方式。参见Python内置函数open()的用法。默认是’a',即添加到文件末尾。

3) logging.handlers.RotatingFileHandler
这个Handler类似于上面的FileHandler,但是它可以管理文件大小。当文件达到一定大小之后,它会自动将当前日志文件改名,然后创建 一个新的同名日志文件继续输出。比如日志文件是chat.log。当chat.log达到指定的大小之后,RotatingFileHandler自动把 文件改名为chat.log.1。不过,如果chat.log.1已经存在,会先把chat.log.1重命名为chat.log.2。。。最后重新创建 chat.log,继续输出日志信息。它的构造函数是:
RotatingFileHandler( filename[, mode[, maxBytes[, backupCount]]])
其中filename和mode两个参数和FileHandler一样。
maxBytes用于指定日志文件的最大文件大小。如果maxBytes为0,意味着日志文件可以无限大,这时上面描述的重命名过程就不会发生。
backupCount用于指定保留的备份文件的个数。比如,如果指定为2,当上面描述的重命名过程发生时,原有的chat.log.2并不会被更名,而是被删除。

4) logging.handlers.TimedRotatingFileHandler
这个Handler和RotatingFileHandler类似,不过,它没有通过判断文件大小来决定何时重新创建日志文件,而是间隔一定时间就 自动创建新的日志文件。重命名的过程与RotatingFileHandler类似,不过新的文件不是附加数字,而是当前时间。它的构造函数是:
TimedRotatingFileHandler( filename [,when [,interval [,backupCount]]])
其中filename参数和backupCount参数和RotatingFileHandler具有相同的意义。
interval是时间间隔。
when参数是一个字符串。表示时间间隔的单位,不区分大小写。它有以下取值:
S 秒
M 分
H 小时
D 天
W 每星期(interval==0时代表星期一)
midnight 每天凌晨

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
import logging
 
#create logger
logger = logging.getLogger('TEST-LOG')
logger.setLevel(logging.DEBUG)
 
 
# create console handler and set level to debug
ch = logging.StreamHandler()
ch.setLevel(logging.DEBUG)
 
# create file handler and set level to warning
fh = logging.FileHandler("access.log")
fh.setLevel(logging.WARNING)
# create formatter
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
 
# add formatter to ch and fh
ch.setFormatter(formatter)
fh.setFormatter(formatter)
 
# add ch and fh to logger
logger.addHandler(ch)
logger.addHandler(fh)
 
# 'application' code
logger.debug('debug message')
logger.info('info message')
logger.warn('warn message')
logger.error('error message')
logger.critical('critical message')

  

  

文件自动截断例子

 import logging

 from logging import handlers

 logger = logging.getLogger(__name__)

 log_file = "timelog.log"
#fh = handlers.RotatingFileHandler(filename=log_file,maxBytes=10,backupCount=3)
fh = handlers.TimedRotatingFileHandler(filename=log_file,when="S",interval=5,backupCount=3) formatter = logging.Formatter('%(asctime)s %(module)s:%(lineno)d %(message)s') fh.setFormatter(formatter) logger.addHandler(fh) logger.warning("test1")
logger.warning("test12")
logger.warning("test13")
logger.warning("test14")

re模块  

常用正则表达式符号

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
'.'     默认匹配除\n之外的任意一个字符,若指定flag DOTALL,则匹配任意字符,包括换行
'^'     匹配字符开头,若指定flags MULTILINE,这种也可以匹配上(r"^a","\nabc\neee",flags=re.MULTILINE)
'$'     匹配字符结尾,或e.search("foo$","bfoo\nsdfsf",flags=re.MULTILINE).group()也可以
'*'     匹配*号前的字符0次或多次,re.findall("ab*","cabb3abcbbac")  结果为['abb''ab''a']
'+'     匹配前一个字符1次或多次,re.findall("ab+","ab+cd+abb+bba") 结果['ab''abb']
'?'     匹配前一个字符1次或0
'{m}'   匹配前一个字符m次
'{n,m}' 匹配前一个字符n到m次,re.findall("ab{1,3}","abb abc abbcbbb") 结果'abb''ab''abb']
'|'     匹配|左或|右的字符,re.search("abc|ABC","ABCBabcCD").group() 结果'ABC'
'(...)' 分组匹配,re.search("(abc){2}a(123|456)c""abcabca456c").group() 结果 abcabca456c
 
 
'\A'    只从字符开头匹配,re.search("\Aabc","alexabc") 是匹配不到的
'\Z'    匹配字符结尾,同$
'\d'    匹配数字0-9
'\D'    匹配非数字
'\w'    匹配[A-Za-z0-9]
'\W'    匹配非[A-Za-z0-9]
's'     匹配空白字符、\t、\n、\r , re.search("\s+","ab\tc1\n3").group() 结果 '\t'
 
'(?P<name>...)' 分组匹配 re.search("(?P<province>[0-9]{4})(?P<city>[0-9]{2})(?P<birthday>[0-9]{4})","371481199306143242").groupdict("city") 结果{'province''3714''city''81''birthday''1993'}

  

最常用的匹配语法

1
2
3
4
5
re.match 从头开始匹配
re.search 匹配包含
re.findall 把所有匹配到的字符放到以列表中的元素返回
re.splitall 以匹配到的字符当做列表分隔符
re.sub      匹配字符并替换

反斜杠的困扰
与大多数编程语言相同,正则表达式里使用"\"作为转义字符,这就可能造成反斜杠困扰。假如你需要匹配文本中的字符"\",那么使用编程语言表示的正则表达式里将需要4个反斜杠"\\\\":前两个和后两个分别用于在编程语言里转义成反斜杠,转换成两个反斜杠后再在正则表达式里转义成一个反斜杠。Python里的原生字符串很好地解决了这个问题,这个例子中的正则表达式可以使用r"\\"表示。同样,匹配一个数字的"\\d"可以写成r"\d"。有了原生字符串,你再也不用担心是不是漏写了反斜杠,写出来的表达式也更直观。

仅需轻轻知道的几个匹配模式

1
2
3
re.I(re.IGNORECASE): 忽略大小写(括号内是完整写法,下同)
M(MULTILINE): 多行模式,改变'^''$'的行为(参见上图)
S(DOTALL): 点任意匹配模式,改变'.'的行为

  

  

Subprocess模块 

The subprocess module allows you to spawn new processes, connect to their input/output/error pipes, and obtain their return codes. This module intends to replace several older modules and functions:

os.system
os.spawn*

The recommended approach to invoking subprocesses is to use the run() function for all use cases it can handle. For more advanced use cases, the underlying Popen interface can be used directly.

The run() function was added in Python 3.5; if you need to retain compatibility with older versions, see the Older high-level API section.

subprocess.run(args*stdin=Noneinput=Nonestdout=Nonestderr=Noneshell=Falsetimeout=Nonecheck=False)

Run the command described by args. Wait for command to complete, then return a CompletedProcess instance.

The arguments shown above are merely the most common ones, described below in Frequently Used Arguments (hence the use of keyword-only notation in the abbreviated signature). The full function signature is largely the same as that of the Popen constructor - apart from timeoutinput and check, all the arguments to this function are passed through to that interface.

This does not capture stdout or stderr by default. To do so, pass PIPE for the stdout and/or stderr arguments.

The timeout argument is passed to Popen.communicate(). If the timeout expires, the child process will be killed and waited for. The TimeoutExpired exception will be re-raised after the child process has terminated.

The input argument is passed to Popen.communicate() and thus to the subprocess’s stdin. If used it must be a byte sequence, or a string if universal_newlines=True. When used, the internal Popen object is automatically created withstdin=PIPE, and the stdin argument may not be used as well.

If check is True, and the process exits with a non-zero exit code, a CalledProcessError exception will be raised. Attributes of that exception hold the arguments, the exit code, and stdout and stderr if they were captured.

常用subprocess方法示例

#执行命令,返回命令执行状态 , 0 or 非0
>>> retcode = subprocess.call(["ls", "-l"])

#执行命令,如果命令结果为0,就正常返回,否则抛异常
>>> subprocess.check_call(["ls", "-l"])
0

#接收字符串格式命令,返回元组形式,第1个元素是执行状态,第2个是命令结果 
>>> subprocess.getstatusoutput('ls /bin/ls')
(0, '/bin/ls')

#接收字符串格式命令,并返回结果
>>> subprocess.getoutput('ls /bin/ls')
'/bin/ls'

#执行命令,并返回结果,注意是返回结果,不是打印,下例结果返回给res
>>> res=subprocess.check_output(['ls','-l'])
>>> res
b'total 0\ndrwxr-xr-x 12 alex staff 408 Nov 2 11:05 OldBoyCRM\n'

#上面那些方法,底层都是封装的subprocess.Popen
poll()
Check if child process has terminated. Returns returncode

wait()
Wait for child process to terminate. Returns returncode attribute.

terminate() 杀掉所启动进程
communicate() 等待任务结束

stdin 标准输入

stdout 标准输出

stderr 标准错误

pid
The process ID of the child process.

#例子
>>> p = subprocess.Popen("df -h|grep disk",stdin=subprocess.PIPE,stdout=subprocess.PIPE,shell=True)
>>> p.stdout.read()
b'/dev/disk1 465Gi 64Gi 400Gi 14% 16901472 104938142 14% /\n'

1
2
3
4
5
6
7
8
9
10
11
>>> subprocess.run(["ls""-l"])  # doesn't capture output
CompletedProcess(args=['ls''-l'], returncode=0)
 
>>> subprocess.run("exit 1", shell=True, check=True)
Traceback (most recent call last):
  ...
subprocess.CalledProcessError: Command 'exit 1' returned non-zero exit status 1
 
>>> subprocess.run(["ls""-l""/dev/null"], stdout=subprocess.PIPE)
CompletedProcess(args=['ls''-l''/dev/null'], returncode=0,
stdout=b'crw-rw-rw- 1 root root 1, 3 Jan 23 16:23 /dev/null\n')

调用subprocess.run(...)是推荐的常用方法,在大多数情况下能满足需求,但如果你可能需要进行一些复杂的与系统的交互的话,你还可以用subprocess.Popen(),语法如下:

1
2
= subprocess.Popen("find / -size +1000000 -exec ls -shl {} \;",shell=True,stdout=subprocess.PIPE)
print(p.stdout.read())

可用参数:

  • args:shell命令,可以是字符串或者序列类型(如:list,元组)
  • bufsize:指定缓冲。0 无缓冲,1 行缓冲,其他 缓冲区大小,负值 系统缓冲
  • stdin, stdout, stderr:分别表示程序的标准输入、输出、错误句柄
  • preexec_fn:只在Unix平台下有效,用于指定一个可执行对象(callable object),它将在子进程运行之前被调用
  • close_sfs:在windows平台下,如果close_fds被设置为True,则新创建的子进程将不会继承父进程的输入、输出、错误管道。
    所以不能将close_fds设置为True同时重定向子进程的标准输入、输出与错误(stdin, stdout, stderr)。
  • shell:同上
  • cwd:用于设置子进程的当前目录
  • env:用于指定子进程的环境变量。如果env = None,子进程的环境变量将从父进程中继承。
  • universal_newlines:不同系统的换行符不同,True -> 同意使用 \n
  • startupinfo与createionflags只在windows下有效
    将被传递给底层的CreateProcess()函数,用于设置子进程的一些属性,如:主窗口的外观,进程的优先级等等

终端输入的命令分为两种:

  • 输入即可得到输出,如:ifconfig
  • 输入进行某环境,依赖再输入,如:python

需要交互的命令示例

1
2
3
4
5
6
7
8
9
10
import subprocess
 
obj = subprocess.Popen(["python"], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
obj.stdin.write('print 1 \n ')
obj.stdin.write('print 2 \n ')
obj.stdin.write('print 3 \n ')
obj.stdin.write('print 4 \n ')
 
out_error_list = obj.communicate(timeout=10)
print out_error_list

subprocess实现sudo 自动输入密码

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
import subprocess
 
def mypass():
    mypass = '123' #or get the password from anywhere
    return mypass
 
echo = subprocess.Popen(['echo',mypass()],
                        stdout=subprocess.PIPE,
                        )
 
sudo = subprocess.Popen(['sudo','-S','iptables','-L'],
                        stdin=echo.stdout,
                        stdout=subprocess.PIPE,
                        )
 
end_of_pipe = sudo.stdout
 
print "Password ok \n Iptables Chains %s" % end_of_pipe.read()

  

  

python 自动化之路 day 06的更多相关文章

  1. python 自动化之路 day 01 人生若只如初见

    本节内容 Python介绍 发展史 Python 2 or 3? 安装 Hello World程序 Python 注释 变量 用户输入 模块初识 .pyc是个什么鬼? 数据类型初识 数据运算 表达式i ...

  2. python 自动化之路 day 05

    内容目录: 列表生成式.迭代器&生成器 装饰器 软件目录结构规范 模块初始 常用模块 1.列表生成式,迭代器&生成器 列表生成式 需求:列表[0, 1, 2, 3, 4, 5, 6, ...

  3. python 自动化之路 day 09 进程、线程、协程篇

    本节内容 操作系统发展史介绍 进程.与线程区别 python GIL全局解释器锁 线程 语法 join 线程锁之Lock\Rlock\信号量 将线程变为守护进程 Event事件 queue队列 生产者 ...

  4. python 自动化之路 day 08 面向对象进阶

    面向对象高级语法部分 经典类vs新式类 静态方法.类方法.属性方法 类的特殊方法 反射 异常处理 面向对象高级语法部分 经典类vs新式类 把下面代码用python2 和python3都执行一下 1 2 ...

  5. PYTHON 自动化之路 (二)

    一.python 模块的使用 模块的使用: import os #调用 os 模块 cmd_s = os.popen("dir").read() #打开路径为结果保存为cmd_sp ...

  6. python 自动化之路 day 00 目录

    目录 初识Python Python基本数据类型 Python基础之函数 Python基础之杂货铺 模块 面向对象 网络编程 HTML CSS JavaScript DOM jQuery Web框架本 ...

  7. python 自动化之路 day 10 协程、异步IO、队列、缓存

    本节内容 Gevent协程 Select\Poll\Epoll异步IO与事件驱动 RabbitMQ队列 Redis\Memcached缓存 Paramiko SSH Twsited网络框架 引子 到目 ...

  8. python 自动化之路 day 01.1 数据类型

    一.变量二.数据类型2.1 什么是数据类型及数据类型分类2.2 标准数据类型:2.2.1 数字2.2.1.1 整型:2.2.1.2 长整型long:2.2.1.3 布尔bool:2.2.1.4 浮点数 ...

  9. python 自动化之路 day 04

    内容目录: 1. 函数基本语法及特性 2. 参数与局部变量 3. 返回值 4.嵌套函数 5.递归 6.匿名函数 7.函数式编程介绍 8.高阶函数 9.内置函数 1.函数基本语法及特性 背景提要 现在老 ...

随机推荐

  1. js/jquery获取文本框的值与改变文本框的值

    我们就用它来学习获取文本框的值及改变文本框的值. 代码如下 复制代码 <script>function get1(){ document.getElementById("txtb ...

  2. 查看oracle表中列的数据类型

    一. SQLPLUS中,直接用 DESC[ribe] tablename 即可. 二.在外部应用程序调用查看ORACLE中的表结构时,只能用下面的语句代替: 1.看字段名与数据类型 select * ...

  3. VS(VisualStudio)中折叠代码、打开代码的快捷键

    CTRL + M, CTRL + O折叠代码定义 CTRL + M, CTRL + L展开代码定义

  4. eoe项目结构

    ├ cn.eoe.app –存放程序全局性类的包├ cn.eoe.app.adapter –存放适配器的实现类的包 ├ cn.eoe.app.adapter.base –存放适配器基类的包├ cn.e ...

  5. 报错:Caused by: java.io.FileNotFoundException: d:\youTemprepository\upload_77faffc1_1580a9240ca__8000_00000001.tmp (系统找不到指定的路径。)

    org.apache.commons.fileupload.FileUploadBase$IOFileUploadException: Processing of multipart/form-dat ...

  6. hibernate中持久化对象的生命周期(三态:自由态,持久态,游离态 之间的转换)

    三态的基本概念: 1,  暂时状态(Transient):也叫自由态,仅仅存在于内存中,而在数据库中没有对应数据.用new创建的对象,它没有持久化,没有处于Session中,处于此状态的对象叫暂时对象 ...

  7. 【图论】【宽搜】【染色】NCPC 2014 A Ades

    题目链接: http://acm.csu.edu.cn/OnlineJudge/problem.php?id=1787 题目大意: N个点M条无向边(N,M<=200000),一个节点只能有一个 ...

  8. Android_自定义进度条

    转载:http://blog.csdn.net/lmj623565791/article/details/43371299 ,本文出自:[张鸿洋的博客] 1.概述 最近需要用进度条,秉着不重复造轮子的 ...

  9. Spring IOC、AOP、Transaction、MVC小结

    1.IOC.AOP:把对象交给Spring进行管理,通过面向切面编程来实现一些“模板式”的操作,使得程序员解放出来,可以更多的关注业务实现.                             - ...

  10. SQL Server OPTION (OPTIMIZE FOR UNKNOWN) 测试总结

      关于SQL Server的查询提示OPTION (OPTIMIZE FOR UNKNOWN) ,它是解决参数嗅探的方法之一. 而且对应的SQL语句会缓存,不用每次都重编译.关键在于它的执行计划的准 ...