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@lonetwin
lonetwin / zodb_undo.py
Created Jun 23, 2011
Snippet to undo zodb transactions upto a specific point in the past
View zodb_undo.py
#!/usr/bin/python
# zodb_undo.py - Snippet to undo zodb transactions upto a specific point in the past
zodb_file = "var/karl.db"
undo_back_to = (2011, 6, 15, 11, 00, 00, 00, 00, 00) # time tuple
import time
import transaction
from ZODB import FileStorage, DB
@lonetwin
lonetwin / print_table.py
Last active May 7, 2021
print out ascii tables in python using data in the form: [ ('column 0 title', 'column 1 title' ..), ('row 0, column 0 data', 'row 0, column 1 data' ...) ...]
View print_table.py
# I needed to print out ascii tables from data in the form:
# [ ('column 0 title', 'column 1 title' ..),
# ('row 0, column 0 data', 'row 0, column 1 data' ...) ...]
#
# and surprisingly it got complicated because of variable lengths of the data.
# I googled for 'standard' ways of doing this and I found suggestions like:
# http://stackoverflow.com/questions/5909873/python-pretty-printing-ascii-tables
# ...which were a bit dated and hard to read or full scale modules like:
#
# http://pypi.python.org/pypi/texttable/
@lonetwin
lonetwin / pythonrc.py
Last active Feb 11, 2020
lonetwin's pimped-up pythonrc - Now at https://github.com/lonetwin/pythonrc
View pythonrc.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# The MIT License (MIT)
#
# Copyright (c) 2015 Steven Fernandez
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
@lonetwin
lonetwin / guitar_scales.py
Created Sep 26, 2013
Python functions to generate the names of the notes for various musical scales, meant to be used for quick reference when practising the guitar.
View guitar_scales.py
#!/usr/bin/env python
notes = ['a', 'a#', 'b', 'c', 'c#', 'd', 'd#', 'e', 'f', 'f#', 'g', 'g#'] * 2
chroma = lambda x: [ i for i in notes[ notes.index(x): ] + notes[ :notes.index(x) ] ] + [x]
major = lambda x: ( chroma(x)[:5] + [chroma(x)[5]] + chroma(x)[5:12] )[::2] + [x]
major_penta = lambda x: [ i for idx, i in enumerate(major(x)) if idx not in (3, 6) ]
minor_penta = lambda x: ( major_penta( notes[ notes.index(x) + 3 ])[:-1] * 2)[-6:]
"""
# for example
@lonetwin
lonetwin / ShowGitHubURL
Last active Dec 29, 2015
Vim function to echo the currently edited file's github url
View ShowGitHubURL
function ShowGitHubURL()
" Function to echo the github URL for the currently open file at the
" current line number. This is useful if for example, you want to quickly
" share the URL for the file you're working on via, email / IRC etc.
"
" This can also be easily extended to open the browser with the displayed
" URL using tips such as http://vim.wikia.com/wiki/VimTip306
"
" You may add a mapping like this to bind this function to a keystroke:
" map <Leader>gh :call ShowGitHubURL()<CR>
@lonetwin
lonetwin / Git dot files management
Last active Oct 8, 2022
A simple way to manage dotfiles with git without silly symlinks and special tools. Just use negative matches in your .gitignore !
View Git dot files management
I like to manage dotfiles without having to mess with silly symlinks or having
to install/configure specific dotfile managament tools. So here's what I did:
$ cd ~
$ git init .
$ echo '*' > .gitignore # ignore all files by default
$ echo '!.bashrc' >> .gitignore # ...and then tell git what files not to *not* ignore
$ # ...add other files you may want to track to *not* ignore
$ git add .bashrc # now actually add the files to git
$ git add .gitignore # add the .gitignore to git
@lonetwin
lonetwin / custom_sftp.py
Last active Oct 4, 2020
Replacing openssh's external sftp server with a custom sftp server based on paramiko [DEPRECATED -- please see comment]
View custom_sftp.py
#!/usr/bin/env python
# A more detailed explaination will come as a blog post soon, but in brief,
# here is the problem that led to this:
#
# For various reasons we have a requirement to implement an 'sftp' like
# abstraction/interface for a service that we provide. Basically we need to
# present objects in our application as a filesystem accessible over sftp.
#
# The way we have decided to go about this is to replace the 'standard' openssh
# sftp subsystem command entry in /etc/ssh/sshd_config on our servers with our
View example.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
def page_category_filter(bid_request, config):
if config["mode"] == "whitelist":
return bool(
bid_request["categories"] & set(config["categories"])
)
else:
return bool(
config["categories"] and not
@lonetwin
lonetwin / locked_open.py
Last active Aug 9, 2022
Simple python file locking context manager example on linux using python stdlib's `fcntl.flock`
View locked_open.py
import logging
import fcntl
from contextlib import contextmanager
@contextmanager
def locked_open(filename, mode='r'):
"""locked_open(filename, mode='r') -> <open file object>
Context manager that on entry opens the path `filename`, using `mode`
(default: `r`), and applies an advisory write lock on the file which
@lonetwin
lonetwin / dlt-log-app.py
Last active Mar 11, 2016
Minimal python ctypes based example of logging to GENIVI Diagnostic Log and Trace Daemon
View dlt-log-app.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Minimal example of writing logs to a dlt-daemon from a python app. The
# message will look like this when printed out using
# "dlt-receive -a localhost":
# 2016/03/10 10:24:42.772153 290716359 016 ECU1 DLTD INTM log info V 1 [ApplicationID 'APPY' registered for PID 29, Description=APPY service]
# 2016/03/10 10:24:42.772178 290716360 017 ECU1 DLTD INTM log info V 1 [ContextID 'APPY' registered for ApplicationID 'APPY', Description=Context for APPY]
# 2016/03/10 10:24:42.772182 290716359 000 ECU1 APPY APPY log info V 1 [This is a log message]
# 2016/03/10 10:24:42.772185 290716360 018 ECU1 DLTD INTM log info V 1 [Unregistered ContextID 'APPY' for ApplicationID 'APPY']
# 2016/03/10 10:24:42.772190 290716360 019 ECU1 DLTD INTM log info V 1 [Unregistered ApplicationID 'APPY']