1. 压缩归档

如果是用于归档文件,那我们最好的选择就是使用压缩工具,python的标准库自带zipfile和tarfile用来压缩归档文件,还有gzip用来为单一文件进行压缩,另外github上还有一个归档为rar的工具rarfile.

1.1. zipfile

zip文件格式由三个部分组成：压缩源文件数据区+压缩源文件目录区+压缩源文件目录结束标志

压缩源文件数据区

在这个数据区中每一个压缩的源文件/目录都是一条记录，记录的格式如下： [文件头+ 文件数据 + 数据描述符]

• 文件头结构

• 文件数据

• 数据描述符

这个数据描述符只在全局方式位标记的第３位设为１时才存在，紧接在压缩数据的最后一个字节后。这个数据描述符只用在不能对输出的 ZIP 文件进行检索时使用。例如：在一个不能检索的驱动器（如：磁带机上）上的 ZIP 文件中。如果是磁盘上的ZIP文件一般没有这个数据描述符。

压缩源文件目录区

在这个数据区中每一条纪录对应在压缩源文件数据区中的一条数据

压缩源文件目录结束标志

import zipfile 

1.1.1. 创建归档

• 创建一个文件的zip归档

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 

• 创建字符串的归档

with open("source/input/iris.csv","r") as f:     content = f.read() 

with zipfile.ZipFile('source/output/iris_str.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.writestr( 'iris_str.csv',content) 

• 创建一个多文件归档

在归档大量文件时,我们可以用allowZip64=True来指定支持超过2Gb的归档

with zipfile.ZipFile('source/output/all_input.zip', 'w',zipfile.ZIP_DEFLATED,allowZip64=True) as f:     f.write("source/input/笑傲江湖.txt")     f.write("source/input/iris.csv")     f.write("source/input/people.json") 

1.1.2. 查看压缩文件信息

#查看是不是zip压缩文件 zipfile.is_zipfile("source/output/all_input.zip") 

True 

# 查看zip中的文件列表 with zipfile.ZipFile('source/output/all_input.zip', 'r',zipfile.ZIP_DEFLATED) as f:     print(f.namelist()) 

['source/input/笑傲江湖.txt', 'source/input/iris.csv', 'source/input/people.json'] 

# 打开zip中某个文件 with zipfile.ZipFile('source/output/all_input.zip', 'r',zipfile.ZIP_DEFLATED) as f:     print(f.open('source/input/people.json').read().decode("utf-8")) 

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 0

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 1

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 2

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 3

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 4

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 5

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 6

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 7

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 8

with zipfile.ZipFile('source/output/笑傲江湖.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.write("source/input/笑傲江湖.txt") 9

with open("source/input/iris.csv","r") as f:     content = f.read() 0

1.1.3. 解压文件

• 全部解压

with open("source/input/iris.csv","r") as f:     content = f.read() 1

• 单独解压一个

with open("source/input/iris.csv","r") as f:     content = f.read() 2

1.1.4. 密码处理

zipfile只能解压带密码的zip包,并不支持创建加密的zip归档,要使用密码只要像这个样:

with open("source/input/iris.csv","r") as f:     content = f.read() 3

即可

1.2. tarfile

tar是linux下是常见的归档格式,常见的后缀有tar,tar.bz,tar.gz三种后缀,分别对应三种不同的压缩算法,

tarfile的归档用法也与zipfile类似,只是接口有些变化

with open("source/input/iris.csv","r") as f:     content = f.read() 4

with open("source/input/iris.csv","r") as f:     content = f.read() 5

with open("source/input/iris.csv","r") as f:     content = f.read() 6

True 

with open("source/input/iris.csv","r") as f:     content = f.read() 8

with open("source/input/iris.csv","r") as f:     content = f.read() 9

with zipfile.ZipFile('source/output/iris_str.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.writestr( 'iris_str.csv',content) 0

['source/input/笑傲江湖.txt', 'source/input/iris.csv', 'source/input/people.json'] 

with zipfile.ZipFile('source/output/iris_str.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.writestr( 'iris_str.csv',content) 2

with zipfile.ZipFile('source/output/iris_str.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.writestr( 'iris_str.csv',content) 3

with zipfile.ZipFile('source/output/iris_str.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.writestr( 'iris_str.csv',content) 4

with zipfile.ZipFile('source/output/iris_str.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.writestr( 'iris_str.csv',content) 5

如果要结合gz或者bz压缩,那么就不能使用这个类,而要使用tarfile.open(name=None, mode='r', fileobj=None, bufsize=10240, **kwargs)函数

其中mode=可选的有:

• 创建压缩归档

with zipfile.ZipFile('source/output/iris_str.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.writestr( 'iris_str.csv',content) 6

• 解压压缩归档

with zipfile.ZipFile('source/output/iris_str.zip', 'w',zipfile.ZIP_DEFLATED) as f:     f.writestr( 'iris_str.csv',content) 7

1.3. rarfile

python标准库并不支持rar格式的归档,但有个rarfile可以通过pip安装,他的接口与zipfile一样,只是不能写只能读