configparser从zip加载配置文件

Question

I am creating a program that loads and runs python scripts from a compressed file. Along with those python scripts, I have a config file that I previously used configparser to load info from in an uncompressed version of the program.

Is it possible to directly read config files in zip files directly with configparser? or do I have to unzip it into a temp folder and load it from there?

I have tried directly giving the path:

>>> sysconf = configparser.ConfigParser()
>>> sysconf.read_file("compressed.zip/config_data.conf")

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.4/configparser.py", line 691, in read_file
    self._read(f, source)
  File "/usr/local/lib/python3.4/configparser.py", line 1058, in _read
    raise MissingSectionHeaderError(fpname, lineno, line)
configparser.MissingSectionHeaderError: File contains no section headers.
file: '<???>', line: 1

Didn't work. no surprises there.

Then I tried using zipfile

 >>> zf = zipfile.ZipFile("compressed.zip")
 >>> data = zf.read("config_data.conf")
 >>> sysconf = configparser.ConfigParser()
 >>> sysconf.read_file(data)

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.4/configparser.py", line 691, in read_file
    self._read(f, source)
  File "/usr/local/lib/python3.4/configparser.py", line 1009, in _read
    if line.strip().startswith(prefix):
AttributeError: 'int' object has no attribute 'strip'

and found that it didn't work either.

so I've resorted to creating a temp folder, uncompressing to it, and reading the conf file there. I would really like to avoid this if possible as the conf files are the only limiting factor. I can (and am) loading the python modules from the zip file just fine at this point.

I can get the raw text of the file if there's a way to pass that directly to configparser, but searching the docs I came up empty handed.

Update: I tried using stringIO as a file object, and it seems to work somewhat. configparser doesn't reject it, but it doesn't like it either.

>>> zf = zipfile.ZipFile("compressed.zip")
>>> data = zf.read(config_data.conf)
>>> confdata = io.StringIO(str(data))
>>> sysconf = configparser.ConfigParser()
>>> sysconf.readfp(confdata)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.4/configparser.py", line 736, in readfp
    self.read_file(fp, source=filename)
  File "/usr/local/lib/python3.4/configparser.py", line 691, in read_file
    self._read(f, source)
  File "/usr/local/lib/python3.4/configparser.py", line 1058, in _read
    raise MissingSectionHeaderError(fpname, lineno, line)
configparser.MissingSectionHeaderError: File contains no section headers.
file: '<???>', line: 1
(continues to spit out the entire contents of the file)

If I use read_file instead, it doesn't error out, but doesn't load anything either.

>>> zf = zipfile.ZipFile("compressed.zip")
>>> data = zf.read(config_data.conf)
>>> confdata = io.StringIO(str(data))
>>> sysconf = configparser.ConfigParser()
>>> sysconf.read_file(confdata)
>>> sysconf.items("General") #(this is the main section in the file)
Traceback (most recent call last):
  File "/usr/local/lib/python3.4/configparser.py", line 824, in items
    d.update(self._sections[section])
KeyError: 'General'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.4/configparser.py", line 827, in items
    raise NoSectionError(section)
configparser.NoSectionError: No section: 'General'

Answer 1

can get the raw text of the file if there's a way to pass that directly to configparser

Try configparser.ConfigParser.read_string

When coupled with an appropriate ZIP file, this code works for me:

import zipfile
import configparser

zf = zipfile.ZipFile("compressed.zip")
zf_config = zf.open("config_data.conf", "rU")
zf_config_data = zf_config.read().decode('ascii')

config = configparser.ConfigParser()
config.read_string(zf_config_data)
assert config['today']['lunch']=='cheeseburger'

Upon reflection, the following might be more appropriate:

import zipfile
import configparser
import io

zf = zipfile.ZipFile("compressed.zip")
zf_config = zf.open("config_data.conf", "rU")
zf_config = io.TextIOWrapper(zf_config)

config = configparser.ConfigParser()
config.read_file(zf_config)
assert config['today']['lunch']=='cheeseburger'

Answer 2

ZipFile not only supports read but also open , which returns a file-like object. So, you could do something like this:

zf = zipfile.ZipFile("compressed.zip")
config_file = zf.open("config_data.conf")
sysconfig = configparser.ConfigParser()
sysconfig.readfp(config_file)

Answer 3

As written in comments, @matthewatabet answer won't work with Python 3.4 (and newer vesions). It's because ZipFile.open now returns a "bytes-like" object and not a "file-like" object anymore. You can use:

codecs.getreader("utf-8")(config_file)

To convert the config_file bytes-like object into a file-like object using the UTF-8 encoding. The code is now:

import zipfile, configparser, codecs

with zipfile.ZipFile("compressed.zip") as zf:
    config_file = zf.open("config_data.conf")
    sysconfig = configparser.ConfigParser()
    sysconfig.read_file(codecs.getreader("utf-8")(config_file))

That seems more satisfactory than creating a string , but I don't know if it's more efficient...