Using ConfigParser, read an .ini file to a dict and remove quotes around string values

June 9, 2018 1 comment

Problem
In Python you can read .ini files easily with the configparser module.

An .ini file looks like this:

[OPTIONS]
name = Jabba

As you can see, string values are not quoted. However, for me it looks lame. IMO a string must be between quotes or apostrophes. With quotes you can also add whitespace characters to the beginning or the end of a string. So I prefer writing this:

[OPTIONS]
name = "Jabba"

But now quotes become part of the string. If you read it with configparser, the value of name is '"Jabba"' instead of 'Jabba'.

Solution
When using configparser, it builds a dict-like object. I prefer to work with normal dictionaries. So first I read the .ini file, then convert the configparser object to dict, and finally I remove quotes (or apostrophes) from string values. Here is my solution:

preferences.ini

[GENERAL]
onekey = "value in some words"

[SETTINGS]
resolution = '1024 x 768'

example.py

#!/usr/bin/env python3

from pprint import pprint
import preferences

prefs = preferences.Preferences("preferences.ini")
d = prefs.as_dict()
pprint(d)

preferences.py

import sys
import configparser
import json
from pprint import pprint

def remove_quotes(original):
    d = original.copy()
    for key, value in d.items():
        if isinstance(value, str):
            s = d[key]
            if s.startswith(('"', "'")):
                s = s[1:]
            if s.endswith(('"', "'")):
                s = s[:-1]
            d[key] = s
            # print(f"string found: {s}")
        if isinstance(value, dict):
            d[key] = remove_quotes(value)
    #
    return d

class Preferences:
    def __init__(self, preferences_ini):
        self.preferences_ini = preferences_ini

        self.config = configparser.ConfigParser()
        self.config.read(preferences_ini)

        self.d = self.to_dict(self.config._sections)

    def as_dict(self):
        return self.d

    def to_dict(self, config):
        """
        Nested OrderedDict to normal dict.
        Also, remove the annoying quotes (apostrophes) from around string values.
        """
        d = json.loads(json.dumps(config))
        d = remove_quotes(d)
        return d

The line d = remove_quotes(d) is responsible for removing the quotes. Comment / uncomment this line to see the difference.

Output:

$ ./example.py

{'GENERAL': {'onekey': 'value in some words'},
 'SETTINGS': {'resolution': '1024 x 768'}}

I also posted this to SO (link here).

JiVE: A general purpose, cross-platform image viewer with some built-in NSFW support, written in Python 3.6 using PyQt5

In the past 2-3 weeks I’ve been working on a general purpose, cross-platform image viewer that has some built-in NSFW support. It’s called JiVE and it’s in Python 3.6 using PyQt5. A unique feature of JiVE is that it allows you to browse online images just as if they were local images.

You can find it on GitHub: https://github.com/jabbalaci/JiVE-Image-Viewer. I also wrote a detailed documentation.

Screenshots

In action:

jive.png

Selecting an NSFW subreddit:

nsfw.png

Read the docs for more info.

install PyQt5

The following is based on this YouTube video.

$ sudo apt install python3-pyqt5
...
$ python3
>>> import PyQt5
>>>
=======================================================================
$ sudo apt install python3-pyqt5.qtsql
...
$ python3
>>> from PyQt5 import QtSql
>>>
=======================================================================
$ sudo apt install qttools5-dev-tools
...
$ ls -al /usr/lib/x86_64-linux-gnu/qt5/bin/designer
lrwxrwxrwx 1 root root 25 ápr   14 09:38 /usr/lib/x86_64-linux-gnu/qt5/bin/designer -> ../../../qt5/bin/designer

I put a symbolic link on designer to launch it easily.

Categories: PyQt5, python

word cloud generator

March 12, 2018 Leave a comment
Categories: python Tags:

unzip: perform the opposite of zip

March 8, 2018 Leave a comment

zip

>>> a = [1, 2, 3]
>>> b = ["one", "two", "three"]
>>> zip(a, b)
<zip object at 0x7fd30310b508>
>>> list(zip(a, b))
[(1, 'one'), (2, 'two'), (3, 'three')]

unzip
How to perform the opposite of zip? That is, we have [(1, 'one'), (2, 'two'), (3, 'three')], and we want to get back [1, 2, 3] and ["one", "two", "three"].

>>> li
[(1, 'one'), (2, 'two'), (3, 'three')]
>>> a, b = zip(*li)
>>> a
(1, 2, 3)
>>> b
('one', 'two', 'three')

Notice that the results are tuples.

More info here.

Categories: python Tags: ,

sanitizing tweets

February 12, 2018 Leave a comment

Problem
You have the text of a tweet and you want to get rid of the bullshit (smileys, emojis, etc.)

Solution
See https://github.com/s/preprocessor. It’s customizable, you can select what to remove, e.g. URLs, smileys, etc.

What are the built-in functions?

January 19, 2018 Leave a comment

Problem
How to figure out the built-in functions in Python? Of course, you can look up the documentation, but now the exercise is to list them in the Python shell.

Solution

In [1]: import builtins

In [2]: dir(builtins)
Out[2]: 
['ArithmeticError',
 'AssertionError',
 'AttributeError',
 'BaseException',
 'BlockingIOError',
 'BrokenPipeError',
 'BufferError',
 'BytesWarning',
 'ChildProcessError',
 'ConnectionAbortedError',
 'ConnectionError',
 'ConnectionRefusedError',
 'ConnectionResetError',
 'DeprecationWarning',
 'EOFError',
 'Ellipsis',
 'EnvironmentError',
 'Exception',
 'False',
 'FileExistsError',
 'FileNotFoundError',
 'FloatingPointError',
 'FutureWarning',
 'GeneratorExit',
 'IOError',
 'ImportError',
 'ImportWarning',
 'IndentationError',
 'IndexError',
 'InterruptedError',
 'IsADirectoryError',
 'KeyError',
 'KeyboardInterrupt',
 'LookupError',
 'MemoryError',
 'ModuleNotFoundError',
 'NameError',
 'None',
 'NotADirectoryError',
 'NotImplemented',
 'NotImplementedError',
 'OSError',
 'OverflowError',
 'PendingDeprecationWarning',
 'PermissionError',
 'ProcessLookupError',
 'RecursionError',
 'ReferenceError',
 'ResourceWarning',
 'RuntimeError',
 'RuntimeWarning',
 'StopAsyncIteration',
 'StopIteration',
 'SyntaxError',
 'SyntaxWarning',
 'SystemError',
 'SystemExit',
 'TabError',
 'TimeoutError',
 'True',
 'TypeError',
 'UnboundLocalError',
 'UnicodeDecodeError',
 'UnicodeEncodeError',
 'UnicodeError',
 'UnicodeTranslateError',
 'UnicodeWarning',
 'UserWarning',
 'ValueError',
 'Warning',
 'ZeroDivisionError',
 '__IPYTHON__',
 '__build_class__',
 '__debug__',
 '__doc__',
 '__import__',
 '__loader__',
 '__name__',
 '__package__',
 '__spec__',
 'abs',
 'all',
 'any',
 'ascii',
 'bin',
 'bool',
 'bytearray',
 'bytes',
 'callable',
 'chr',
 'classmethod',
 'compile',
 'complex',
 'copyright',
 'credits',
 'delattr',
 'dict',
 'dir',
 'display',
 'divmod',
 'enumerate',
 'eval',
 'exec',
 'filter',
 'float',
 'format',
 'frozenset',
 'get_ipython',
 'getattr',
 'globals',
 'hasattr',
 'hash',
 'help',
 'hex',
 'id',
 'input',
 'int',
 'isinstance',
 'issubclass',
 'iter',
 'len',
 'license',
 'list',
 'locals',
 'map',
 'max',
 'memoryview',
 'min',
 'next',
 'object',
 'oct',
 'open',
 'ord',
 'pow',
 'print',
 'property',
 'range',
 'repr',
 'reversed',
 'round',
 'set',
 'setattr',
 'slice',
 'sorted',
 'staticmethod',
 'str',
 'sum',
 'super',
 'tuple',
 'type',
 'vars',
 'zip']
Categories: python Tags:

BASE64 as URL parameter

January 1, 2018 Leave a comment

Problem
In a REST API, I wanted to pass a URL as a BASE64-encoded string, e.g. “http://host/api/v2/url/aHR0cHM6...“. It worked well for a while but I got an error for a URL. As it turned out, a BASE64 string can contain the “/” sign, and it caused the problem.

Solution
Replace the “+” and “/” signs with “-” and “_“, respectively. Fortunately, Python has functions for that (see here).

Here are my modified, URL-safe functions:

def base64_to_str(b64):
    return base64.urlsafe_b64decode(b64.encode()).decode()

def str_to_base64(s):
    data = base64.urlsafe_b64encode(s.encode())
    return data.decode()

You can also quote and unquote a URL instead of using BASE64:

>>> url = "https://www.youtube.com/watch?v=V6w24Lg3zTI"
>>>
>>> import urllib.parse
>>>
>>> new = urllib.parse.quote(url)
>>>
>>> new
>>> 'https%3A//www.youtube.com/watch%3Fv%3DV6w24Lg3zTI'    # notice the "/" signs!
>>>
>>> urllib.parse.quote(url, safe='')
>>> 'https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DV6w24Lg3zTI'    # no "/" signs!
>>>
>>> new = urllib.parse.quote(url, safe='')
>>>
>>> urllib.parse.unquote(new)
>>> 'https://www.youtube.com/watch?v=V6w24Lg3zTI'
Categories: python Tags: , , ,

convert a file to an UTF-8-encoded text

December 16, 2017 Leave a comment

I wrote a simple script that takes an input file, changes its character encoding to UTF-8, and prints the result to the screen.

It’s actually a wrapper around the Unix commands “file” and “iconv“. The goal was to make its usage as simple as possible. The script is here: to_utf8.py.

Usage:

$ to_utf8.py input.txt

The program tries to detect the encoding of the input file.

Links

Categories: bash, python Tags: ,

work in a temp. dir. and delete it when done

December 11, 2017 Leave a comment

Problem
You want to work in a temp. directory, and delete it completely when you are done. You also need the name of this temp. folder.

Solution
You can write with tempfile.TemporaryDirectory() as dirpath:, and the temp. dir. will be removed automatically by the context manager when you quit the with block. Nice and clean.

import tempfile
from pathlib import Path

with tempfile.TemporaryDirectory() as dirpath:
    fp = Path(dirpath, "data.txt")
    # create fp, process it, etc.

# when you get here, dirpath is removed recursively

More info in the docs.

Categories: python Tags: ,
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