Quick reminder of how to split a "ls -l" listing. It is problematic because the last field which is the directory or file name can have spaces itself, so splitting on spaces which is the only option here still need a bit of additional work.

import config
import subprocess

## First experiment doing manual manipulation of the fields.  
## Basically split on all spaces and then assemble the file name.
def dir_listing():
  ls_lines = subprocess.check_output(['ls', '-l']).splitlines()
  ls_arr= []
  for item in ls_lines:
    if not "total" in item:
      f = item.split()
      ## fname = item.join(str(v) for v in item.index if v > 7)
      fname = ""
      for idx,val in enumerate(f):
        if idx > 7:
          fname = fname + str(val) + " "
      fname = fname[:-1]
      ls_fields = [f[0],f[1],f[2],f[3],f[4],f[5]+"-"+f[6]+"-"+f[7],fname]
      ls_arr.append(ls_fields)
  return ls_arr

## Second attempt is split on spaces with a max split defined. 
## This sounds like the obvious way to do this but I needed to use "None" and not " "
## as shown below.
def dir_listing_optimized():
  ls_lines = subprocess.check_output(['ls', '-l']).splitlines()
  ls_arr= []
  for item in ls_lines:
    if not "total" in item:
      ## None will use arbitrary strings of whitespace characters (space, tab, newline, return, formfeed)
      ## When using split(" ",8) I had more separation than I expected and therefor my last field 
      ## was not working right.
      f = item.split(None,8)
      ls_arr.append(f)
  return ls_arr

for dir in dir_listing():
  print dir

for dir in dir_listing_optimized():
  print dir

A short write up on how to bootstrap a webpy app and at the same time show how to make a system call with popen.  I based this short app on the skeleton example here: http://webpy.org/skeleton/0.3

Just a note on where my test live for my own reference later.

$ pwd
/DATA/src/hvInfo

$ ls
call1.py call.pyc config.pyc hvInfo.pyc my test with spaces_ and more... templates view.pyc web.py-0.37
call.py config.py hvInfo.py index.html simpleHTTP.py view.py web web.py-0.37.tar

Main python app:

hvInfo.py

import web
import view, config
from view import render

urls = (
  '/', 'index'
)

class index:
  def GET(self):
    return render.base(view.listing())

if __name__ == "__main__": 
  app = web.application(urls, globals())
  app.run()

Define some functions here:

call.py

import config
#from subprocess import Popen, PIPE
import subprocess

def listing_experiment1():
    cmd = "ls -l ~/"
    p = Popen(cmd , shell=True, stdout=PIPE, stderr=PIPE)
    #out, err = p.communicate()
    #print "Return code: ", p.returncode
    #return out.rstrip(), err.rstrip()
    outputlines = filter(lambda x:len(x)>0,(line.strip() for line in p.stdout))
    return outputlines
    #return out.replace('\n','<br>')

    ##return config.DB.select('items', **k)

def dir_listing():
  ## http://stackoverflow.com/questions/8880461/python-subprocess-output-to-list-or-file
  ls_lines = subprocess.check_output(['ls', '-l']).splitlines()
  ## I want to pass output as separate fields but space as a delimiter won't do the trick since filenames can have spaces...
  ls_arr= []
  for item in ls_lines:
    if not "total" in item:
      f = item.split()
      #fname = item.join(str(v) for v in item.index if v > 7)
      fname = ""
      for idx,val in enumerate(f):
        if idx > 7:
          fname = fname + str(val) + " "
      fname = fname[:-1]
      ls_fields = [f[0],f[1],f[2],f[3],f[4],f[5]+"-"+f[6]+"-"+f[7],fname]
      ls_arr.append(ls_fields)
  return ls_arr

Lets maintain a config file. Especially when DB access becomes necessary.

config.py

import web
#DB = web.database(dbn='postgres', db='appname', user='username', pw='')
cache = False

Following MVC type framework.  It makes sense to keep presentation separate.

view.py

import web
import call
import config

t_globals = dict(
  datestr=web.datestr,
)
render = web.template.render('templates/', cache=config.cache, 
    globals=t_globals)
render._keywords['globals']['render'] = render

def listing():
    l = call.dir_listing()
    return render.listing(l)

Templates as follow:

$ cat templates/base.html

$def with (page, title=None)
<html><head>
<title>hvInfo\
$if title: : $title\
</title>
</head><body>
<h1><a href="/">hvInfo</a></h1>
$:page   
</body></html>

$ cat templates/listing.html

$def with (items)
  <table>
  $for item in items:
    <tr><td>$item[0]<td>$item[1]<td>$item[2]<td>$item[3]<td>$item[4]<td>$item[5]<td><b>$item[6]</b>
  </table>

$ cat templates/item.html

$def with (item)

$item

Run web server as follow:

$ python hvInfo.py
http://0.0.0.0:8080/

Test in browser at this link: http://localhost:8080/

Sometimes I want to email from Python and this is pretty easy. Or even just testing mail flow I prefer this over good old "telnet host 25" since we have well constructed headers with smtplib.

#!/usr/bin/python
import datetime
import os
import sys
import smtplib

def warnEmail(SMTPserver, Subject, Body):
 fromaddr = "rrosso@domain.com"
 #toaddrs = ["rcpt1@domain.com","rcpt2@domain.com"]
 toaddrs = ["hostmaster@domain.com"]

 msg = ("From: %s\r\nTo: %s\r\nSubject: %s\r\n\r\n" % (fromaddr, ", ".join(toaddrs),Subject))
 
 server = smtplib.SMTP(SMTPserver)
 msg = msg + Body
 #server.set_debuglevel(1)
 server.sendmail(fromaddr, toaddrs, msg)
 server.quit()

SMTPserver =  'mailhost'
warnEmail(SMTPserver, "Test through " + SMTPserver , "Body test goes \n here!")

Quick sort routine...

def sort(array):
  if len(array) <= 1: return array
  mid = len(array) // 2
  return merge (sort(array[0:mid]), sort(array[mid:]))

# this may not be the most thoroughly idiomatic python, or the
# most efficient merge (it duplicates data when "Transmitting")
# but it works
def merge(left, right):
    merged = []

    i = 0
    j = 0
    while(len(merged) < len(left)+len(right)):
        if left[i] < right[j]:
            merged.append(left[i])
            i += 1
            if i == len(left):
                # Knuth, TaoCP Vol 3 5.2.4 Calls this the "transmit"       
                y = right[j:]
                for x in y:
                    merged.append(x)
                break
        else:
            merged.append(right[j])
            j += 1
            if j == len(right):
                y = left[i:]
                for x in y:
                    merged.append(x)
                break

    return merged

a=[1,3,2,4]
b=sort(a)
print b

Quick and simple Python list with node insert capabilty.

class Node:
    def __init__(self,value):
        self.data = value
        self.next = 0

class List:
    def __init__(self):
        self.firstNode = Node(0)
    def __ShowNodeData(self,aNode):
        if aNode.next != 0:
           print aNode.data
           self.__ShowNodeData(aNode.next)
    def Dump(self):
        self.__ShowNodeData(self.firstNode)
    def InsertAfter(self,aNode,aNewNode):
        aNewNode.next = aNode.next
        aNode.next = aNewNode
    def InsertBeginning(self,aNewNode):
        aNewNode.next = self.firstNode
        self.firstNode = aNewNode   

nodeA = Node("A")
nodeB = Node("B")
nodeC = Node("C")
nodeD = Node("D")

aList = List()

aList.InsertBeginning(nodeB)
aList.InsertAfter(nodeB,nodeD)
aList.InsertAfter(nodeD,nodeC)
aList.InsertAfter(nodeC,nodeA)
 
aList.Dump()