Drill through a Login with Python

import urllib2
import urllib
import BeautifulSoup

# build opener with HTTPCookieProcessor
o = urllib2.build_opener( urllib2.HTTPCookieProcessor() )
urllib2.install_opener( o )

# assuming the site expects 'user' and 'pass' as query params
p = urllib.urlencode( { 'username': 'myusername', 'password': 'mypassword' } )

# perform login with params
f = o.open( 'https://www.mysite.com/login', p )
data = f.read()
f.close()

# second request should automatically pass back any
# cookies received during login... thanks to the HTTPCookieProcessor
f = o.open( 'http://www.mysite.com/home/' )
data = f.read()
f.close()

soup = BeautifulSoup.BeautifulSoup(data)

http://www.nomadjourney.com/2009/03/automatic-site-login-using-python-urllib2/

Python String format

Python Format dates into strings
from datetime import date
d1 = date(2010,01,23)
d2 = date(2010,01,23)
"%s - %s" % (d1.strftime("%m / %d / %Y"), d1.strftime("%m / %d / %Y"))

Python Unicode Convert

Convert weird unicode string characters to string:
import unicodedata
unicodedata.normalize('NFKD',unicode_string).encode('ascii','ignore')

Django module for helping convert things to ascii strings:
from django.utils.encoding import smart_str
smart_str('weird string goes here')

Another hack for removing unicode errors:
unicode('my weird string', errors='ignore')


http://docs.python.org/howto/unicode.html#the-unicode-type

matplotlib basics

Simple Plot
import matplotlib.pyplot as plt
plt.plot([1,2,3,4])
# plot a set of points (1,1) and (3,2)
plt.plot([1,3],[1,2],'ro')
# Or plot as a bunch of connect line segments
plt.plot([2,4,6],[2,4,6])
# set a label for the x and y axis
plt.ylabel('some numbers')
plt.xlabel('joe rocks')
# set the axis [xmin, xmax, ymin, ymax ]
plt.axis([0,6,0,5])
# 'show' the graph
plt.show()


Plot a function
As far as I can tell matplotlib cannot plot a continuous function.  
Instead, create a range of distinct numbers:

import numpy as np
import matplotlib.pyplot as plt
# create a range of numbers from 0 to 5. increment by .1
x = np.arange(0.,5.,.1)
# apply a function to that 
y = np.sin(x)
# plot with extra display params
plt.plot(x,y,linewidth=2.0, label='joeplot', color='blue')
plt.title(r'$\alpha_i > \beta_i$', fontsize=20)
plt.axis([0,5,-1,1])
plt.grid(True)
plt.show()

Make a cool heatmap
import numpy as np
import matplotlib.pyplot as plt
#x = y = np.linspace(-5, 5, 12)
# create a grid of 12 X coordinates and 12 Y coordinates 
# these coordinates will be used to represent specific locations on 
# the grid.  the meshgrid() basically creates a nice uniform coordinate grid
X,Y = np.meshgrid([1,2,3,4],[1,2,3])
# X,Y = np.meshgrid(x, y)
# these ravel functions basically make the 2d arrays created above into lists
x = X.ravel()
y = Y.ravel()
plt.subplot(111)
plt.hexbin(x,y,C=[1,2,3,3,2,2,3,3,2,3,3,4], gridsize=30)
cb = plt.colorbar()
cb.set_label('Heat Value')
plt.axis([x.min(), x.max(), y.min(), y.max()])
plt.grid(True)


http://stackoverflow.com/questions/2369492/generate-a-heatmap-in-matplotlib-using-a-scatter-data-set

Case Study Notes: install pyqrcode in a virtualenv on OSX

Kind of a buggy install.

mkdir qrcode; cd qrcode
virtualenv --distribute --no-site-packages ve
source ./ve/bin/activate
echo "pil" > requirements.pip
echo "http://svn.apache.org/repos/asf/lucene/pylucene/trunk/jcc" >> requirements.pip

wget http://downloads.sourceforge.net/pyqrcode/pyqrcode-0.2.1.tar.gz?use_mirror=

cd pyqrcode-0.2.1

# EDIT pyqrcode-0.2.1/Makefile
# change the call to jcc from
GENERATE=python -m jcc --jar $(LIBFILE) \
# TO
GENERATE=python -m jcc.__main__ --jar $(LIBFILE) \

make
make egg

# it will create qrcode-0.2.1-py2.6-macosx-10.6-universal.egg
# Edit qrcode-0.2.1-py2.6-macosx-10.6-universal.egg/qrcode/__init__.py
# change the line
_qrcode._setExceptionTypes(JavaError, InvalidArgsError)
# TO
_qrcode._set_exception_types(JavaError, InvalidArgsError)

pip -E ./ve/ install qrcode-0.2.1-py2.6-macosx-10.6-universal.egg

# http://pyqrcode.sourceforge.net/
# http://www.mail-archive.com/pythonmac-sig@python.org/msg09864.html
# http://mail-archives.apache.org/mod_mbox/lucene-pylucene-dev/200904.mbox/%3C49EEECAC.7070606@cheimes.de%3E

Installing MySQL-python (MySQLdb) in a virtualenv on OSX 10.6

There were two problems with the MySQL-Python package that I had when installing on OS X 10.6
1) First, an error saying "EnvironmentError: mysql_config not found" when setup.py is run (through pip or easy_install)
2) Second, an error saying "ImportError: dynamic module does not define init function(init_mysql) when importing MySQLdb" when 'import MySQLdb" is issued

Causes:
1) This is caused by the build script not being able to find a MySQL program called mysql_config. This program is used to determine metadata about the mysql install. For example, the command "mysql_config --cflags" reports the flags used to build mysql.
2) This is caused by a mismatch between the architectures that MySQL was built with and the architecture that MySQL-python installer is trying to build and install MySQL-python as. To find what arch MySQL was built as, run "mysql_config --cflags" (this was i386 in my case). OSX tries to build MySQL-python as x86_64. Therefore, there is a arch mismatch.

Solution:
1) Locate the mysql_config binary location and add the path to the MySQL-python/site.cfg file as a config directive: "mysql_config = /opt/local/bin/mysql_config5"
2) Use the arch x86_64 (64 bit) version of MySQL compiled through MacPorts, not a i386 (32 bit) version downloaded off the internet and installed as a dmg.

Summary:
Assuming the MacPorts version of MySQL is installed, both issues can be solved by adding the mysql_config = /opt/local/bin/mysql_config5 config directive to the MySQL-python/site.cfg file.

# SCRIPTED SOLUTION: Create a script called setup.sh and add the following lines
virtualenv --distribute --no-site-packages ve
source ./ve/bin/activate
pip install -E ./ve -r requirements.1.pip # other deps
export ARCHFLAGS="-arch x86_64"
pip install -E ./ve MySQL-python
echo "mysql_config = /opt/local/bin/mysql_config5" >> ./ve/build/MySQL-python/site.cfg
pip install -E ./ve MySQL-python


Resources:
http://groups.google.com/group/python-virtualenv/msg/cf4f3117faea476b?pli=1
http://birdhouse.org/blog/2009/02/21/python-mysql-connections-on-mac-os/
http://stackoverflow.com/questions/2111283/how-to-build-64-bit-python-on-os-x-10-6-only-64-bit-no-universal-nonsense

Python Pip Usage

Basic PIP install
pip install somepackage

Basic PIP uninstall
pip uninstall somepackage

Requirements file
# cat requirements.txt
MyApp
Framework==0.0.1
Library>=0.2

Installing using a requirements file
pip install -r requirements.pip

PIP Freezing requirements
pip freeze # lists all packages and the specific version installed. Useful for migrating

PIP install into virtualenv env
pip install -E ./env
pip install -E ./env -r requirements.pip # using a requirements file

Basic script for creating a virtualenv and installing requirements
virtualenv --distribute --no-site-packages ve
source ./ve/bin/activate
pip install -E ./ve -r requirements.pip
pip install -E ./ve -r requirements-test.pip

http://heisel.org/blog/2009/11/21/django-hudson/
http://pip.openplans.org/#freezing-requirements

Case Study Notes: install djangobb in virtualenv

Ubuntu 10.04 python 2.6 django 1.1

sudo apt-get build-dep python-psycopg2
sudo aptitude install python-dev

cd Sites
virtualenv --no-site-packages env
. ./env/bin/activate
pip install pil
pip install markdown2 Markdown
pip install django-registration
pip install djapian
pil install xapian
pip install psycopg2
easy_install -i http://downloads.egenix.com/python/index/ucs4/ egenix-mx-base
pip install http://code.djangoproject.com/svn/django/tags/releases/1.1.2/
hg clone http://hg.djangobb.org/djangobb/ djangobb
cd env/lib/python2.6/site-packages/
cp /usr/lib/python2.6/dist-packages/_xapian.so .
cp /usr/lib/python2.6/dist-packages/xapian.py .

# configure settings.py to use postgresql_psycopg2
# comment out the openid stuff

## http://www.saltycrane.com/blog/2009/07/using-psycopg2-virtualenv-ubuntu-jaunty/

Postgresql Basic Commands

Login to postgresql:
psql -d mydb -U myuser -W
psql -h myhost -d mydb -U myuser -W
psql -U myuser -h myhost "dbname=mydb sslmode=require" # ssl connection

Default Admin Login:
sudo -u postgres psql -U postgres
sudo -u postgres psql

List databases on postgresql server:
psql -l [-U myuser] [-W]

Turn off line pager pagination in psql:
\pset pager

Determine system tables:
select * from pg_tables where tableowner = 'postgres';

List databases from within a pg shell:
\l

List databases from UNIX command prompt:
psql -U postgres -l

Describe a table:
\d tablename

Quit psql:
\q

Switch postgres database within admin login shell:
\connect databasename

Reset a user password as admin:
alter user usertochange with password 'new_passwd';

Show all tables:
\dt

List all Schemas:
\dn

List all users:
\du

Load data into posgresql:
psql -W -U username -H hostname < file.sql

Dump (Backup) Data into file:
pg_dump -W -U username -h hostname database_name > file.sql

Increment a sequence:
SELECT nextval('my_id_seq');

Create new user:
CREATE USER jjasinski WITH PASSWORD 'myPassword';
# or
sudo -u postgres createuser jjasinski -W

Change user password:
ALTER USER Postgres WITH PASSWORD 'mypass';

Grant user createdb privilege:
ALTER USER myuser WITH createdb;

Create a superuser user:
create user mysuper with password '1234' SUPERUSER
# or even better
create user mysuper with password '1234' SUPERUSER CREATEDB CREATEROLE INHERIT LOGIN REPLICATION;
# or
sudo -u postgres createuser jjasinski -W -s

Upgrade an existing user to superuser: 
alter user mysuper with superuser;
# or even better
alter user mysuper with SUPERUSER CREATEDB CREATEROLE INHERIT LOGIN REPLICATION

Show Database Version:
SELECT version();

Change Database Owner:
alter database database_name owner to new_owner;

Copy a database:
CREATE DATABASE newdb WITH TEMPLATE originaldb;
http://www.commandprompt.com/ppbook/x14316

View Database Connections:
SELECT * FROM pg_stat_activity;

View show data directory (works on 9.1+; not on 7.x):
show data_directory;

Show run-time parameters:

show all;
select * from pg_settings;

Show the block size setting:
# show block_size;
 block_size
------------
 8192
(1 row)

Show stored procedure source:
SELECT prosrc FROM pg_proc WHERE proname = 'procname'

Grant examples:
# readonly to all tables for myuser
grant select on all tables in schema public to myuser;
# all privileges on table1 and table2 to myuser
grant all privileges on table1, table2, table3 to myuser;

Restore Postgres .dump file:
pg_restore --verbose --clean --no-acl --no-owner -h localhost -U myuser -d mydb latest.dump
source

Find all active sessions and kill them (i.e. for when needing to drop or rename db)
Source: http://stackoverflow.com/questions/5408156/how-to-drop-a-postgresql-database-if-there-are-active-connections-to-it

# Postgres 9.2 and above
SELECT pg_terminate_backend(pg_stat_activity.pid) 

FROM pg_stat_activity 

WHERE pg_stat_activity.datname = 'TARGET_DB' 

 AND pid <> pg_backend_pid();

# Postgres 9.1 and below
SELECT pg_terminate_backend(pg_stat_activity.procpid) 

FROM pg_stat_activity 

WHERE pg_stat_activity.datname = 'TARGET_DB' 

AND procpid <> pg_backend_pid();


Re-read postgres config without dropping connections (i.e. if postgres.conf or pg_hba.conf changes)
Source: http://www.heatware.net/databases/postgresql-reload-config-without-restarting/

/usr/bin/pg_ctl reload
or
SELECT pg_reload_conf();

Per user query logging (logs to to postgres logs):
alter role myuser set log_statement = 'all';


Sources:
http://www.devdaily.com/blog/post/postgresql/log-in-postgresql-database
http://forums.devshed.com/postgresql-help-21/how-do-you-turn-off-more-scroll-lock-at-psql-174831.htm
http://www.cyberciti.biz/faq/howto-add-postgresql-user-account/
http://archives.postgresql.org/pgsql-general/1998-08/msg00050.php
http://stackoverflow.com/questions/876522/creating-a-copy-of-a-database-in-postgres
http://stackoverflow.com/questions/1137060/where-does-postgresql-store-the-database

Recycle bin script

crm()
{
# pass this function the name of the directory that
# you want to backup and remove 
if [ -d "$1" ]
then
  cd "${1}/../"
else
  echo "Directory does not exist"
  return 1
fi

PWD=`pwd`
BKPFILES=`find $PWD -type -f`
BKPDIR="$HOME/.Trash"
daten=`date +%Y.%m.%d-%H.%M.%S`

for i in $BKPFILES
do
  echo "$i"
  DIRNAME="$BKPDIR"`echo ${i%/*}`
  FILENAME=`echo ${i##*/}`
  mkdir -p "$DIRNAME"
  cp -pf "$i" "${DIRNAME}/${FILENAME}.${daten}"
  #NEWFILE=`echo "$i" | sed 's|[ \/]|_|g'`
  print "$i"  "$NEWFILE"   " $DIRNAME"
done
rm -rf "$1"
cd - 
}

OSX Color LS

Color LS for Mac OX
alias ls='ls -G'

sftp notes

sftp using alternate port:
sftp -oPort=2222 username@host.com

sftp using alternate private key file:

sftp -o IdentityFile=/custom/file/location.pem username@host.com

http://www.unix.com/shell-programming-scripting/43334-sftp-scripting-help-required.html

Basic Python Development Server setup with Ubuntu 10.04

Quick setup guide

# config vi command line
echo "set -o vi" >> ~/.bashrc
. ~/.bashrc

# install packages
aptitude install vim openssh-server apache2 python-virtualenv python-mysqldb mysql-server libapache2-mod-php5 libapache2-mod-wsgi eclipse subversion nmap ubuntu-restricted-extras g++ git-gui virtualbox-ose php5-cli mdadm fabric python-dev mercurial

# eclipse development plugins
install pydev for eclipse
install subclipse for eclipse

# firefox development plugins
install firebug for firefox @ http://getfirebug.com/
install web developer for firefox @ https://addons.mozilla.org/en-US/firefox/addon/60/

# add google repo
deb http://dl.google.com/linux/deb/ stable non-free
aptitude update

cd /opt/
wget http://www.djangoproject.com/download/1.1.2/tarball/
wget http://www.djangoproject.com/download/1.2.1/tarball/
tar -xvf Django-1.1.2.tar.gz
tar -xvf Django-1.2.1.tar.gz
cd /usr/lib/python2.6/dist-packages
ln -s /opt/Django-1.2.1/django/ django

# mysql workbench download (64 bit version)
aptitude install libzip1 python-pysqlite2 # deps needed
http://dev.mysql.com/get/Downloads/MySQLGUITools/mysql-workbench-oss-5.2.22-1ubu1004-amd64.deb/from/http://mirror.services.wisc.edu/mysql/
dpkg -i mysql-workbench-oss-5.2.22-1ubu1004-amd64.deb

# setup postgresql
aptitude install postgresql pgadmin3 python-psycopg2

sudo su -
passwd postgres
su postgres
psql template1

The last instruction should open the psql shell, where you can run the following:

ALTER USER postgres WITH ENCRYPTED PASSWORD 'mypassword';

# Setup NX server (Google NeatX server)
sudo apt-get install python-software-properties && sudo add-apt-repository ppa:freenx-team
sudo apt-get update
sudo apt-get install neatx-server

## NOTE: if neatx gives a weird error, delete the session dirs on the server:
## /var/lib/neatx/sessions/some_dir/

https://help.ubuntu.com/community/FreeNX
http://programmingzen.com/2007/12/26/installing-django-with-postgresql-on-ubuntu/

Simple Network Test Script

This is a simple script to log network outages on a local network

root@ubuntu:/mnt/root/usr/local/bin# more lifeline
#!/bin/bash

PING='/bin/ping'
EXTHOST1='www.google.com'
EXTHOST2='sun.iwu.edu'
INTHOST='192.168.1.1'
LOG='/var/log/network_outages'
WAITTIME=120

echo "NETWORK STATUS SCRIPT: Started " `date` >> $LOG
while [ 1=1 ]
do
   dater=`date +%Y.%m.%d-%H.%M.%S`
   $PING -q -c1 $EXTHOST1
   ret=$?
   echo "RET: $ret"
   if [ $ret -ne 0 ]
   then
     echo "EXTERNAL_PING(1): outage detected $dater" >> $LOG
   fi

   dater=`date +%Y.%m.%d-%H.%M.%S`
   $PING -q -c1 $EXTHOST2
   ret=$?
   echo "RET: $ret"
   if [ $ret -ne 0 ]
   then
     echo "EXTERNAL_PING(2): outage detected $dater" >> $LOG
   fi

   $PING -q -c1 $INTHOST
   ret=$?
   echo "RET: $ret"
   if [ $ret -ne 0 ]
   then
     echo "INTERNAL_PING: outage detected $dater" >> $LOG
   fi

   sleep $WAITTIME
done

Simple HEX Editor

View file in Hex Editor
od -cx filename

Bash String Operatinos

Remove the last four characters in a string
echo "somefile.txt" | awk 'sub("....$","")

Remove file extension from a string
ls -1 | sed 's/\(.*\)\..*/\1/'

Remove PREFIX from SOMEPATH
SOMEPATH="/home/myuser/usr/bin/"
PREFIX="/home/myuser/"
echo ${SOMEPATH#$PREFIX}
Returns: usr/bin/

Remove shortest match of PREFIX from SOMEPATH
SOMEPATH="/home/sub/subhome/myuser/usr/bin/"
PREFIX="/*/myuser/"
echo ${SOMEPATH#$PREFIX}
Returns: usr/bin/

Parsing parts of a file:
foo=/tmp/my.dir/filename.tar.gz
To get: /tmp/my.dir (like dirname)
path = ${foo%/*}
To get: filename.tar.gz (like basename)
file = ${foo##*/}
To get: filename
base = ${file%%.*}
To get: tar.gz
ext = ${file#*.}

Removing first 8 characters of a string:
echo $var | cut -c9-

http://unstableme.blogspot.com/2008/03/printremove-first-some-characters-of.html
http://tldp.org/LDP/LGNET/18/bash.html
http://docstore.mik.ua/orelly/unix/upt/ch09_07.htm
http://unstableme.blogspot.com/2007/12/removing-last-two-characters-bash.html
http://www.unix.com/shell-programming-scripting/40360-remove-file-extension.html

Oracle Login Context Information

Find the Database instance you are logged into
SELECT sys_context('USERENV', 'DB_NAME') FROM dual;
SELECT sys_context('USERENV', 'INSTANCE_NAME') FROM dual;

Find the operating system user hosting the Oracle session
SELECT sys_context('USERENV', 'OS_USER') FROM dual;

Find the Oracle user currently logged into
SELECT sys_context('USERENV', 'SESSION_USER') FROM dual;

http://www.psoug.org/reference/sys_context.html

Python Virtual Env

Download and install via apt-get, ports, easy_install, etc.

Locate the install directory (usually site-packages) and find the virtualenv.py script.
Alternatively, the package manager may have installed a virtualenv script into your PATH.

I will use ENV to refer to /path/to/python/virtual/env
I will use virtualenv.py to refer to /path/to/script/virtualenv.py

Create a new Virtual Environment
python virtualenv.py ENV

(optional) Activate (set PATH and PYTHONPATH) for new Virtual ENV
source ENV/bin/activate

Location of Virtual Env python binary
ENV/bin/python

Location of Virtual ENV python site-packages dir
ENV/lib/python2.x/site-packages/

Location of Virtual ENV python easy_install script
ENV/bin/easy_install


http://pypi.python.org/pypi/virtualenv

curl Usage

Send a POST

curl -u joe:1234 -X POST http://localhost:8000/api/1.0/NU1yWdRM5JBjnZpZX/message/ -d "message=test"

-u = username and password

-d = post parameters

-X = request method

Send a POST using data from standard in:
echo "mykey=myvalue" | curl -X POST -d @-  https://mysite.com/

Show verbose output: 
curl -v http://mysite.com/

Ignore SSL key errors:
curl -k http://mysite.com/

Combining them: 
echo "TEST=1
TEST2=2
" curl -X POST -vk -d @- http://mysite.com/

netbios name lookups

Find NetBIOS name from IP
Windows:
netstat -a 192.168.1.22

Linux:
nbtstat 192.168.1.22 # ntbstat separate package

Find IP from NetBIOS name
Windows:
nbtstat -a host.example.com

Linux:
nmblookup host.example.com

http://www.irongeek.com/i.php?page=security/ipinfo

MacPorts Usage

Update MacPorts itself
sudo port selfupdate
sudo port -d selfupdate # debug

Updates the port tree with new versions definitions
sudo port sync

List available ports
sudo port list

Search ports
port search [keyword]

Lookup package info (desc, maintainer, etc)
port info [package]

Find package dependencies
port deps [package]

Install package
sudo port install [package]
sudo port -v install [package] #verbose

Clean out build files and tarballs
port clean --all [pakcage]

Uninstall a package
sudo port uninstall [package]

Show port contents
port contents [package]

List installed packages
port installed

List outdated ports
port outdated

Upgrade specific packages
port upgrade [package]
port upgrade outdated #updates all outdated packages


http://guide.macports.org/chunked/using.html

DJango Model Inheritance with subclasses

http://www.djangosnippets.org/snippets/1034/
http://www.djangosnippets.org/snippets/1031/
http://adam.gomaa.us/blog/2009/feb/16/subclassing-django-querysets/
http://docs.djangoproject.com/en/dev/ref/contrib/contenttypes/

Python List Operations (map, for comprehensions)

EXAMPLE 1
# Create a list
>>> l = [1,2,3,4,5,6]

# iterate through the list using a for comprehension
>>> [i for i in l]
[1, 2, 3, 4, 5, 6]

# square elements in the list using a for comprehension
>>> [i**2 for i in l]
[1, 4, 9, 16, 25, 36]

# square only even elements in the list using a for comprehension
>>> [i**2 for i in l if i % 2 == 0]
[4, 16, 36]

# iterate through the list using map
>>> map(lambda w: w, l)
[1, 2, 3, 4, 5, 6]

# square each element of the list using map
>>> map(lambda w: w**2, l)
[1, 4, 9, 16, 25, 36]

# or use map to call a separately defined function to# iterate through the list
>>> def squa(x):
...... return x**2

>>> map(squa, l)
[1, 4, 9, 16, 25, 36]

# use map function to call a separately defined function that takes 2 args
>>> l2 = map(lambda w: (w,2),l)
>>> l2
[(1, 2), (2, 2), (3, 2), (4, 2), (5, 2), (6, 2)]

>>> def pow(base, expo):
...... return base**expo

>>> map(lambda (x,y): pow(x,y), l2)
[1, 4, 9, 16, 25, 36]

# filter a list
>>> filter(lambda w: w > 2, l)
[3, 4, 5, 6]

EXAMPLE 2
# define a simple class to play with
>>> class A(object):
...... def __init__(self, x):
........ self.x = x

# create simple list of object instances of the class
>>> l = [A(1), A(2), A(3)]

# use a for (list) comprehension to iterate through the list
>>> [i.x for i in l]
[1, 2, 3]

# use a for comprehension to iterate with a condition
>>> [i.x for i in l if i.x > 1]
[2, 3]

# use map to apply a function to every element in the list
>>> map(lambda w: w.x, l)
[1, 2, 3]

>>> map(lambda w: w.x * w.x, l)
[1, 4, 9]

EXAMPLE 1

# Create a list

>>> l = [1,2,3,4,5,6]

# iterate through the list using a for comprehension

>>> [i for i in l]

[1, 2, 3, 4, 5, 6]

# square elements in the list using a for comprehension

>>> [i**2 for i in l]

[1, 4, 9, 16, 25, 36]

# square only even elements in the list using a for comprehension

>>> [i**2 for i in l if i % 2 == 0]

[4, 16, 36]

# iterate through the list using map

>>> map(lambda w: w, l)

[1, 2, 3, 4, 5, 6]

# square each element of the list using map

>>> map(lambda w: w**2, l)

[1, 4, 9, 16, 25, 36]

# or use map to call a separately defined function to# iterate through the list

>>> def squa(x):

...... return x**2

>>> map(squa, l)

[1, 4, 9, 16, 25, 36]

# use map function to call a separately defined function that takes 2 args

>>> l2 = map(lambda w: (w,2),l)

>>> l2

[(1, 2), (2, 2), (3, 2), (4, 2), (5, 2), (6, 2)]

>>> def pow(base, expo):

...... return base**expo

>>> map(lambda (x,y): pow(x,y), l2)

[1, 4, 9, 16, 25, 36]

# filter a list

>>> filter(lambda w: w > 2, l)

[3, 4, 5, 6]

EXAMPLE 3

# split a list into chunks

>>> map(None, *(iter(range(10)),) * 3)

[(0, 1, 2), (3, 4, 5), (6, 7, 8), (9, None, None)]

http://stackoverflow.com/questions/1335392/iteration-over-list-slices

Django South Migrations

Install Django South

- Place the untared 'south' folder into your Django applicaion

- Modify the project's settings.py and add 'south' to the INSTALLED_APPS list

- For new Django projects:

---1) initialize any Django apps or models to monitor with South.

----a) See Initializing Applications below

---2) run ./manage.py syncdb

---3) run ./manage.py migrate

To view help on startmigration:  # South 7.x+ uses the schemamigration command instead

./manage.py startmigration

Usage: ./manage.py startmigration appname migrationname [--initial] [--auto]

[--model ModelName] [--add-field ModelName.field_name] [--freeze] [--stdout]

Initializing Applications - needed whenever you want to track more Django apps

# this creates a 'migrations' folder in your Django app directory

./manage startmigration app_name comment --initial  # updates for South 7.x+
./manage schemamigration app_name comment --initial # Init's all models in application
./manage startmigration app_name --initial # updates for South 7.x+

./manage schemamigration app_name --initial # comment is optional here

Adding South with no data and no existing models.py objects:
# 1) syncdb as normal
python manage.py syncdb
# 2) Start an application if needed
python manage.py startapp appname
# 3) create a migration file with a blueprint to create tables
python manage.py startmigration appname --initial  # updates for South 7.x+
python manage.py schemamigration appname --initial
# 4) Apply the blueprint and create the tables
python manage.py migrate appname

# 5) Repeat steps 3 and 4 for each additional app if needed

Adding south with no data and existing models.py objects:
# 1) syncdb as normal if needed
python manage.py syncdb
# 2) create a migration file with a blueprint to create tables
python manage.py startmigration appname --initial # updates for South 7.x+
python manage.py schemamigration appname --initial
# 3) Apply the blueprint but it doesn't actually create the tables
python manage.py migrate appname --fake
# 4) Repeat steps 2 and 3 for each additional app if needed

Applying changes after making changes to a model (repeat for each app):
# Creates a migration 'blueprint' file and guesses what should take place
python manage.py startmigration appname migrationname --auto # updates for South 7.x+
python manage.py schemamigration appname migrationname --auto
# OR create the blueprint file but it will be empty
python manage.py startmigration appname migrationname  # updates for South 7.x+
python manage.py schemamigration appname migrationname
# make any modifications needed
# migrate the tables in the app
python manage.py migrate appname
# OR migrate all tables in all apps
python manage.py migrate

Adding a new model to an app already managed with south:
./manage startmigration app_name comment --model m1 --model m2 # updates for South 7.x+
./manage schemamigration app_name comment --model m1 --model m2 # inits specific models

List available migrations
python manage.py migrate --list

http://south.aeracode.org/wiki/ConvertingAnApp

Oracle Space queries

Get Used space for current user
SELECT sum(bytes)/(1024 * 1024) as "Used (MB)"
FROM user_SEGMENTS
ORDER BY 1 desc

Get tablespace usage for all users using that tablespace
select owner, sum(bytes)/power(2,20)mb
from dba_extents
where tablespace_name = 'TABLESPACE'
group by owner
order by 2 desc;

Get Total tablespace available for current user
select tablespace_name,round(sum(bytes) / (1024 * 1024),2) "Tablespace SIZE (MB)"
from user_free_space
group by tablespace_name

Get space of individual tables/indexes (objects) in a schema
select sum(bytes) / (1024 * 1024) as MB,owner,segment_type, segment_name
from dba_segments s
where owner = 'SCHEMA'
group by owner,segment_type, segment_name
order by MB desc

Get USER_ dictornary Tables
SELECT table_name, comments
FROM dictionary
WHERE table_name LIKE 'USER_%'
ORDER BY table_name;

http://snipplr.com/view/4748/get-a-list-of-all-the-user-tables-oracle/
http://www.freelists.org/post/oracle-l/dba-extents-vs-dba-segments,8

CSS Pre Tag formatting

Make pre tags wrap as expected

pre {
white-space: pre-wrap;       /* css-3 should we be so lucky... */
white-space: -moz-pre-wrap;  /* Mozilla, since 1999 */
white-space: -pre-wrap;      /* Opera 4-6  */
white-space: -o-pre-wrap;    /* Opera 7  */
word-wrap: break-word;       /* Internet Explorer 5.5+ */
_white-space: pre;   /* IE only hack to re-specify in addition to
word-wrap  */
}

http://archivist.incutio.com/viewlist/css-discuss/55677
http://bavotasan.com/tutorials/how-to-wrap-text-within-the-pre-tag-using-css/

Relative to Absolute Path in Shell Script

Simple bash function to convert relative paths to absolute pats
fun_abs
{ echo “`cd \`dirname $1\`; pwd`/`basename $1`” }

http://www.robertpeaslee.com/index.php/converting-a-relative-path-to-an-absolute-path-in-bash/

UPDATE: unfortuately the above only works for directories that exist - the perl hack will get around this

fun_abs
{FILE=`$PERL -e "use File::Spec::Functions qw[rel2abs];print rel2abs('$1');"`; echo "$FILE"; }

Get File Extension in Shell Script

Returns the last file extension in the file name
echo "thisfile.txt.log"awk -F . '{print $NF}' # returns "log"

http://liquidat.wordpress.com/2007/09/29/short-tip-get-file-extension-in-shell-script/

Correct CSS PNG Color Mismatch

Copied from link below
Mac OS X will render the images using the color profile they got stored, actually png gamma correction would be more exact. This is not immediately apparent because at a glance the files may look identical but using the pngs over a CSS background color often reveals an unpleasant sight on the mac, especially on Safari.
To prevent such a color mismatch either use a different image format or strip the png gamma correction. In the case of the latter, pngcrush does a pretty good job.
I was pleasantly surprised that I could install it with ease on Fedora ("yum install -y pngcrush"). To use it run:

pngcrush -rem gAMA -rem cHRM -rem iCCP -rem sRGB png-file-name optimized-png-file-name


http://www.viseztrance.com/2009/02/fixing-the-png-color-mismatch-on-mac-os-x.html

vim settings

# start vim with an alternate vimrc location
vim -u filename

# Turn compatibility mode off via set command
:set nocompatible

# view special characters in a vim session
:set list
:set nolist # disable

# set search result hilighting
:set hlsearch

# use different visible characters to see special characters in vim
:set listchars=eol:$,tab:>-,trail:~,extends:>,precedes:< :set list # view line numbers
:set nu
:set nonu # disable

# enable linewrap (on by default)
:set wrap
:set nowrap #disable

# indenting source code (setup)
:set et # expand tabs to spaces
:set sw=4
:set smarttab

# Manually choose the language for syntax highlighting

:setf language
:setf html  # example

# The available languages for syntax highlighting 

# can be found in the vim install directory.  

# In my system, it was /usr/share/vim/vim72/syntax


# indenting source code (usage)
1) in command mode press v to and arrows to select a range of lines
2) after selecting, press ==

http://vim.wikia.com/wiki/Indenting_source_code

# indent multiple lines (not necessarily source code)
1) in command mode press v and arrows to select a range of lines
2) type shift >
shift < will shift a block back

# compatibility mode
# by default, vim will enter into compatibility mode when loading.
# Disable this behavior one of two ways
# 1) Create a .vimrc in your home directory
# 2) Within the vim command line, type :set nocompatible

# trim whitespace at end of line
:1,$s/[ <tab>]*$//

# get vim to return the previous position when editing files

" Tell vim to remember certain things when we exit
"  '10 : marks will be remembered for up to 10 previously edited files
"  "100 : will save up to 100 lines for each register
"  :20 : up to 20 lines of command-line history will be remembered
"  % : saves and restores the buffer list
"  n... : where to save the viminfo files
set viminfo='10,\"100,:20,%,n~/.viminfo

" when we reload, tell vim to restore the cursor to the saved position
augroup JumpCursorOnEdit
au!
autocmd BufReadPost *
\ if expand(":p:h") !=? $TEMP |
\ if line("'\"") > 1 && line("'\"") <= line("$") |
\ let JumpCursorOnEdit_foo = line("'\"") |
\ let b:doopenfold = 1 |
\ if (foldlevel(JumpCursorOnEdit_foo) > foldlevel(JumpCursorOnEdit_foo - 1)) |
\ let JumpCursorOnEdit_foo = JumpCursorOnEdit_foo - 1 |
\ let b:doopenfold = 2 |
\ endif |
\ exe JumpCursorOnEdit_foo |
\ endif |
\ endif
" Need to postpone using "zv" until after reading the modelines.
autocmd BufWinEnter *
\ if exists("b:doopenfold") |
\ exe "normal zv" |
\ if(b:doopenfold > 1) |
\ exe "+".1 |
\ endif |
\ unlet b:doopenfold |
\ endif
augroup END

http://vim.wikia.com/wiki/Restore_cursor_to_file_position_in_previous_editing_session

http://ubuntuforums.org/showthread.php?t=789327
http://www.oualline.com/vim-cook.html
http://stackoverflow.com/questions/1675688/make-vim-show-all-white-spaces-as-a-character
http://jamesreubenknowles.com/set-vim-syntax-language-270

svn+ssh on alternate port

Setup the config
# Add the following lines to ~/.subversion/config
# must be put in the [tunnels] section of the config file
sshnew=ssh -l user -p 2222

Execute the svn:
svn co svn+sshnew://servername.com/path/to/repository/

Djanog show model query

Show the raw SQL generated by a model access: 

# DEBUG needs to be set True 

>>> from django.db import connection 

>>> connection.queries [{'sql': 'SELECT polls_polls.id,polls_polls.question,polls_polls.pub_date FROM polls_polls', 'time': '0.002'}]

sql # The raw SQL statement 
time # How long the statement took to execute, in seconds.

Reset the queries list returned above:
>>> from django import db
>>> db.reset_queries()

Show SQL for a given query (newer django version; 1.5+?)
>>> Product.objects.all().query.sql_with_params()

Show SQL for a given query (older django version; 1.2-1.5+?)
>>> Product.objects.all().query.as_sql()

http://docs.djangoproject.com/en/dev/faq/models/
http://docs.djangoproject.com/en/dev/faq/models/#how-can-i-see-the-raw-sql-queries-django-is-running

http://stackoverflow.com/questions/2314920/django-show-log-orm-sql-calls-from-python-shell

Secure Django Location with htaccess file (webfaction)

Basic steps to secure a Django account using htaccess file
note, this examples assumes apache 2.2, in which the basic auth apache module changed.
note, this example uses a WebFaction account but can be applied to any Django Apache install.

1) Execute this command to create an htpassword file
htpasswd -c /home/my_account/webapps/evesch/apache2/conf/.mypasswds my_user

2) Execute this command to create a htgroups file
echo "managers: my_user" > /home/my_account/webapps/evesch/apache2/conf/.mygroups

3) Modify your httpd.conf file to look like this.
############# contents of /home/my_account/webapps/evesch/apache2 #####
ServerRoot "/home/my_account/webapps/evesch/apache2"

LoadModule dir_module modules/mod_dir.so
LoadModule env_module modules/mod_env.so
LoadModule log_config_module modules/mod_log_config.so
LoadModule mime_module modules/mod_mime.so
LoadModule python_module modules/mod_python.so
LoadModule rewrite_module modules/mod_rewrite.so

# added by me (joe)
LoadModule auth_basic_module modules/mod_auth_basic.so
LoadModule authn_file_module modules/mod_authn_file.so
LoadModule authz_user_module modules/mod_authz_user.so
LoadModule authz_groupfile_module modules/mod_authz_groupfile.so


KeepAlive Off
Listen 7637
LogFormat "%{X-Forwarded-For}i %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined
CustomLog logs/access_log combined
ServerLimit 2

<Location "/">
PythonHandler django.core.handlers.modpython
PythonPath "['/home/my_account/webapps/evesch', '/home/my_account/webapps/evesch/lib/python2.5'] + sys.path"
SetEnv DJANGO_SETTINGS_MODULE myproject.settings
SetHandler python-program

# added by me (joe)
AuthType Basic
AuthName "Under Construction"
AuthUserFile /home/my_account/webapps/evesch/apache2/conf/.mypasswds
AuthGroupFile /home/my_account/webapps/evesch/apache2/conf/.mygroups
Require group managers
</Location>

##############################################

4) restart your apache server and web browser
/home/my_account/webapps/evesch/apache2/bin/stop
/home/my_account/webapps/evesch/apache2/bin/start


http://forum.webfaction.com/viewtopic.php?id=2363

Show RAM Memory Usage (Linux)

Show RAM used by given user (in MB)
ps -u your_username -o rss,command | grep -v peruser | awk '{sum+=$1} END {print sum/1024}'

Show RAM used by individual process (in KB)
ps -u your_username -o rss,pid,command


http://forum.webfaction.com/viewtopic.php?id=2356

Compile httpd (Apache)

Http Configure options

./configure --enable-so --with-mpm=worker --prefix=/opt/httpd/http2.2/ --enable-rewrite --enable-alias --with-port=8080 --enable-cgi --enable-spelling | tee jjj.configure | tee jjj.configure
make | tee jjj.make
make install | tee jjj.make

mod_python Configure options

./configure --with-apxs=/opt/httpd/http2.2/bin/apxs --with-python=/opt/python2.6/bin/python
make
make install


http://cavedoni.com/2005/django-osx

Change keyboard in X

http://ubuntu-tutorials.com/2008/01/31/changing-the-system-keyboard-mapping-on-ubuntu-dvorak-vs-qwerty/
http://xorg.freedesktop.org/archive/X11R7.0/doc/html/setxkbmap.1.html

Find Usage

"Grep" through each file in a directory:
ls xargs grep -i 'STRING'

List all directories and subdirectories in a directory
find . -type d

List all files in a directory no recursion
# workaround for "parameter list is too long".
find . \( ! -name . -prune \) -name 'STRING*' -print
find . -maxdepth 1 -name 'STRING*' -print # GNU find only

Remove all files in a directory no recursion
# workaround for "parameter list is too long".
find . \( ! -name . -prune \) -name 'STRING*' -print -exec rm {} \;

Find a file with a given inode and delete it
ls -lai # lists the inodes next to the files
find . -inum 12345 -exec rm {} \; # finds and removes by inode

http://www.faqs.org/qa/qa-1381.html
http://sial.org/howto/shell/

Django Model Many-to-One

Define the models

from django.db import models

class Reporter(models.Model):
.. first_name = models.CharField(max_length=30)
.. last_name = models.CharField(max_length=30)
.. email = models.EmailField(blank=True, null=True)

def __unicode__(self):
.. return u"%s %s" % (self.first_name, self.last_name)

class Article(models.Model):
.. headline = models.CharField(max_length=100)
.. pub_date = models.DateField()
.. reporter = models.ForeignKey(Reporter, blank=True, null=True)

def __unicode__(self):
.. return self.headline

.. class Meta:
.... ordering = ('headline',)

------------------------------------------------
Add some objects
# import models from core.models
>>> from core.models import Reporter, Article
>>> from datetime import datetime # needed for inserting current time
# add some reporters
>>> r1 = Reporter(first_name="Joe", last_name="Jaz")
>>> r1.save()
>>> r2 = Reporter(first_name="Jane", last_name="Smith")
>>> r2.save()
# add some articles
>>> a1 = Article(headline="Article1", pub_date=datetime(2008,10,14))
>>> a1.reporter = r1 # can add separately
>>> a1.save()
>>> a2 = Article(headline="Article2", pub_date=datetime(2008,10,15), reporter=r2)
>>> a2.save()
# show an article's reporter
>>> a1.reporter
<Reporter: Joe Jaz>
>>> a2.reporter.first_name
'Jane'
# create an article "under" a Reporter via the Reporter object
# the 'article_set' method is generated on model creation using the lower-case model name
# the create method automatically does a save()
>>> a3 = r1.article_set.create(headline="Article3", pub_date=datetime.now())
>>> a3.headline
'Article3'
>>> a3
<Article: Article1> # returns object with Article type
>>> a3.reporter
<Reporter: Joe Jaz> # returns object with Reporter type - the article reporter
# create an article with no reporter and then add it to a particular reporters set of articles
# the add method automatically does a save()
>>> a4 = Article(headline="Article4", pub_date=datetime.now())
>>> r2.article_set.add(a4)
# show all of the given reporter's articles
>>> r2.article_set.all()
[<Article: Article2>, <Article: Article4>]
# count the number of articles that belong to a reporter
>>> r2.record_set.count()
2
>>> r1.record_set.count()
2
# associate article 4 with reporter 1 (instead of reporter 2)
>>> r1.article_set.add(a4)
# we can assign it back and use different syntax this time
>>> a4.reporter = r2
>>> a4.save()
# we can assign multiple articles to a reporter at a time
# this syntax calls save automatically
>>> r1.article_set = [a2, a4]
# we can create an article and assign it with a reporter_id instead of the reporter object
# the reporter_id field is generated with the model
>>> a5 = Article(headline="Article5",pub_date=datetime.now(),reporter_id=r1.id)
>>> a5.save()
# or reporter_id can be a string
>>> a6 = Article(headline="Article6",pub_date=datetime.now(), reporter_id="1")
>>> a6.save()
# Do a query to find reporters of article 1 and article 3
>>> Reporter.objects.filter(article__in=[a1,a3])

http://www.djangoproject.com/documentation/models/many_to_one/

Django OneToMany & ManyToMany Recursive Models

Define the models in core.models.

from django.db import models

class Place(models.Model):
.. name = models.CharField(max_length=50);
.. parent = models.ForeignKey('self', null=True);

.. def __unicode__(self):
.... return "%s > %s" % (self.name,self.parent )

class Fan(models.Model):
.. name = models.CharField(max_length=8)
.. idol = models.ManyToManyField('self', null=True)

.. def __unicode__(self):
.... return self.name

----------------------------------------------------------
Interact with a Foreign Key (One to Many)

# import Place model
from core.models import Place
# add a Place and save
world = Place(name="Earth", parent=None)
world.save()
# add two Places with the world as a parent
country1 = Place(name="US", parent=world)
country1.save()
country2 = Place(name="UK", parent=world)
country2.save()
# add two Places with the US as a parent
city1 = Place(name="Chicago")
city1.parent = country1 # make the association through an update
city1.save()
city2 = Place(name="New York", parent=country1) # associate through insert
city2.save()
# select all the places
Place.objects.all()

------------------------------------------------------
Interact with a Many to Many model

from core.models import Fan

# Define 2 people
person1 = Fan(name="Joe")
person1.save()
person2 = Fan(name="Jane")
person2.save()
# associate the two people
person1.idol.add(person2)

------------------------------------------------------

Java Jar Commands

Creating the File structure
# simple suggested structure
project_directory/
\
_ bin/ # binary files
\_ byte_file.class # compiled java bytecode
_src/ # source files (optional)
_META-INF/ # standard location for manifest file
\_MANIFEST.MF # manifest file containing jar variables

Editing the MANIFEST.MF
The manifest can contain variables such as the following:
Main-Class: class_name # name of a class with a "main" method that will run when jar is run.
Class-path: path/to/classes/in/package/ # path start at root of package

Create the Jar
jar -cvfm jar_name.jar path/to/manifest.mf dir/to/class/files/
jar -cvfm project.jar META-INF/MANIFEST.MF bin/
-c # compress into a jar
-v # verbose output
-f # compress to a file specified on the command line (versus to stdout)
-m # specify a path to a manifest file.

Execute the Jar
java -jar jar_name.jar

Extract a Jar file
jar -xvf jar_name.jar

SSH Client Persistance

Keep SSH connections from timing out
On your client, add this line to your /etc/ssh/ssh_config:
ServerAliveInterval 30

Sound Card Info

Check what ALSA soundcards are available on a Linux system:
cat /proc/asound/cards

Check what features each ALSA card has:
cat /proc/asound/devices
# note that the left number column corresponds to a soundcard in the above list

List sound cards detected
aplay -l

Set the default sound card:
# Enter this into /etc/asound.conf or .asoundrc

pcm.!default {
type hw
card 1
}
ctl.!default {
type hw
card 1
}

Using alsamixer to select which sound card to affect: 
alsamixer -c <sound_card_number_from_proc> 

Using mplayer with a non-default sound device
mplayer -ao oss:/dev/dsp *.mp3 # device 0
mplayer -ao alsa:device=hw=0.0 *.mp3 # device 0
mplayer -ao oss:/dev/dsp1 *.mp3 # device 1
mplayer -ao alsa:device=how=1.0 *.mp3 # device 1


http://seehuhn.de/pages/alsa
http://ubuntuforums.org/showthread.php?t=747054

Sendmail/Postfix Info

Sendmail view mailq:
mailq
sendmail -bp

Sendmail view verbose info:
sendmail -v

Postfix flush mail queue:
sudo postfix flush
sudo postfix -f

Remove all mail in queue: 
sudo postsuper -d ALL

Remove all mail in deferred queue: 
sudo postsuper -d ALL deferred

Postfix Info
http://www.akadia.com/services/postfix_mta.html

http://www.cyberciti.biz/tips/howto-postfix-flush-mail-queue.html
http://www.unix.com.ua/orelly/networking/tcpip/ch10_08.htm
http://shinphp.blogspot.com/2011/09/ubuntu-clean-sendmail-queue.html

Join UNIX Command

Join takes two sorted text files and joins them together on common keys, similar to the Join SQL statements.

Basic join syntax:
join file1 file2

Specify a delimiter other than the default of whitespace (for input and output):
join -t: file1 file2 # sets the delimiter to be a colon


Join on specific columns in each file:
join -1 1 -2 1 file1 file2 # this will make file1's first column join with the file2's first column.

Join on a specific column and output specific columns:
join -11 -21 -o 1.1 1.2 2.1 2.2 file1 file2 # the -o options takes space-seperated arguments that take the form of file.column to specify only particular columns.

Specify filler text in a result column when two keys do not match between files:
join -e "none" file1 file2 -o 1.1 1.2 2.1 2.2 # the -e option needs to be used with -o

http://www.softpanorama.org/Tools/join.shtml
http://www.computerhope.com/unix/ujoin.htm

Compile Python 2.5 From Source

Download from Python web page
http://www.python.org/

UnTAR and enter the directory
tar -jxvf Python-2.5.2.tar.bz2
cd Python-2.5.2

Configure using an alternate install dir
(use ./configure -h for config options)
./configure --prefix=/opt/python/

Build and install the software
make | tee makelog
make test | tee maketestlog
make install | tee makeinstalllog
This will create a python binary. If you specified the prefix, it will put it in the bin/ directory under the prefix directory. However, this compiles the command line python version. To get it working with Apache, preform the following.

Download mod_python
http://www.modpython.org/

Untar and enter into the directory
tar -zxvf mod_python-3.3.1.tgz
cd mod_python-3.3.1

Configure mod_python.
It needs to know where python binary to use, and the apache build tool apxs is located during the configure.

./configure \
--with-apxs=/usr/sbin/apxs \ # the apache build tool
--with-python=/opt/python25/bin/python2.5 \ # path to python binary
| tee output.config
make | tee output.make
make install | tee output.makeinstall

make install should place a binary module in /etc/httpd/modules
(or /usr/lib/httpd/modules)
The module will be called mod_python.so

Configure Apache
You will need to tell Apache to load the module by adding the following line in the Apache configuration file (httpd.conf)

LoadModule python_module modules/mod_python.so
<Directory /path/to/somewhere >
  AddHandler mod_python .py
  PythonHandler mptest
  PythonDebug On
</Directory>

Imaging Support
To be able to manipulate images with python, you need the PIL library. Download it from http://www.pythonware.com/products/pil/
After untaring and entering the directory, install by: python setup.py install
It will copy files into your default (`which python`) python install.

http://www.modpython.org/live/current/doc-html/inst-apacheconfig.html