Dictionnary vs Class for configuration

[Larry Bates]

Ultimately you must answer to your professor, but...

I firmly believe that configuration parameters belong
in a configuration file.  ConfigParser module handles
these very well.  Essentially it builds the dictionary
for you in the form of a ConfigParser class instance.
Then when you wish to change a parameter, edit the
config file and the next time the program runs it reads
the new parameters.  You didn't mention your platform,
but I do a lot on Windows and "freeze" my programs using
py2exe, so configuration files come in really handy to
make those "run-time" variables available to the program.
I also find that people are quite comfortable editing
these files.

Config file would look something like:

[database]
name=nanana
userdb=bob
password=********

[other]
timetosleep=100
path=/home/script

program to read this:

import sys
def ini_error(section, option):
    #
    # Insert code here to handle missing parameters
    #
    print "Unable to locate section=%s, option=%s in .INI file" % (section,
option)
    sys.exit(2)


import ConfigParser
ini_filename="/directory/where/config/stored/program.ini"
INI=ConfigParser.ConfigParser()
INI.read(ini_filename)

section="database"
option="name"
try:    database=INI.get(section, option)
except: ini_error(section, option)

option="userdb"
try:    userdb=INI.get(section, option)
except: ini_error(section, option)

option="password"
try:    password=INI.get(section, option)
except: ini_error(section, option)

section="other"
option="name"
try:    timetosleep=INI.getint(section, option)
except: timetosleep=100

option="path"
try:    path=INI.get(section, option)
except: ini_error(section, option)

You get the idea.

Regards,
Larry Bates
Syscon, Inc.

"Famille Delorme" <fadelorme at free.fr> wrote in message
news:40929016$0$8635$626a14ce at news.free.fr...
> Sorry if this discussion are already submited, but I don't find anything
> really interresting for me.
> And sorry for my bad english, it is not my native language.
>
> I wrote a program in Python for a school project and I am in trouble.
> I have make a Python script called conf.py. This file contains
dictionnarys
> for configuration like this:
> config_sql = {
>                 "DATABASE" : "nanana",
>                 "USERDB" : "bob",
>                 "PASSWORD" : "********"
>                     }
> config_script = {
>                 "TIMETOSLEEP" : 100
>                 "PATH" : "/home/script"
>                 }
> The config_section variable is included in each modules (script python)
used
> in my program
> (with from config.py import config_section)
> And the use is like this
>     from conf.py import config_sql
>     print config["DATABASE"]
>
> But my master say it's better to do a class like this
> class config :
>     def __init__(self, part=="") :
>         if (part=="SQL") :
>             self.database="nanana"
>             self.userdb="bob"
>             self.password="*******"
>         elif (part=="SCRIPT") :
>             self.timetosleep=10
>             self.path="/home/script"
>         ....
>
> and the use like this
>     from conf.py import config
>     cfg=config("SQL")
>     print cfg.database
>
> We have do only a file for configuration because the administrator is no
> searching for configuration.
> I want know :
>  - what is more faster, dictionnary method or class method?
>  - what use more ram memory ?
>  - if you are administrator, what method you like for configure program ?
>
> Note:
>     *  the class will not have methods, it is not necessary.
>     * the program is composed of several modules which import
> config_section.
>
>
> Thank you for futures answers,
> 3Zen
>
>
>
>
>
>