Log datestamped strings to a .csv file

event_logger.py

#!/usr/bin/env python

"""
Event logger
The basic idea is just to provide an interface dedicated to manual data 
logging.  It will log the exact date and time that the user enters strings,
and allow it to be formatted for output in various ways.

Should be able to prompt the user to enter something at a given interval.

endolith@gmail.com 2009-03-05
"""

import os
import csv
from datetime import datetime


def get_file_name():
    '''Ask user for file name and make it valid'''
    # TODO: get log file name name from command line arguments
    print 'Enter name for log file or press <Enter> for datestamp'
    name = raw_input()
    if not name:
        name = 'Log ' + datetime.now().isoformat()
    # Sanitize for Windows - is there a standard function for this?
    name = name.replace(':','_')
    if not name.lower().endswith('.csv'):
        name += '.csv'
    return name

def add_to_log(entry):
    '''Add an entry to both the memory log and CSV log'''
    log.append(entry)
    logWriter.writerow(entry)
    log_file.flush()


# main:
log_file_name = get_file_name()
while os.path.exists(log_file_name):
    print '\nFile ' + log_file_name + ' already exists'
    log_file_name = get_file_name()


# Both a list of lists in memory and a csv file on disk - maybe useful later?
log_file = open(log_file_name, 'wb')
logWriter = csv.writer(log_file)
log = []

add_to_log(['Time', 'Event'])

print '\nEnter log events followed by <Enter>'
print 'Enter "end" when done\n'

event = ''

while event != 'end':
    print '>',
    event = raw_input()
    time_stamp = datetime.now()    
    add_to_log([time_stamp, event])

#for timestamp, event in log:
#    print timestamp.isoformat() + ',' + event
#    print timestamp.strftime('%Y-%m-%d %H:%M:%S') + ',' + event

log_file.close()
print '\nData has been written to file ' + log_file.name

# Stupid Windows closes the terminal after it executes
print '\nPress Enter to close'
raw_input()

You can also use AutoHotkey to press Tab and enter a timestamp every time you press the numpad Enter key, which may or may not be better.