OK, I got the ObjectConfig and Validate downloads, and copied your
Global class successfully. Don't I need to get the two files into
Python as a module? How does that work?
Marc Tompkins wrote:
On Wed, Feb 18, 2009 at 7:30 AM, Wayne
Watson <sierra_mtnv...@sbcglobal.net>
wrote:
See Subject. I've run across
a 58 page document
<http://www.voidspace.org.uk/python/configobj.html>,
but am
uncertain of its applicability to my present needs (see my thread on
"Changing the Attribute"). Usually, I end up with some 3-4 page
document, so this raises an eyebrow. Am I on the right trail? In the
meantime, I think I'll turn it into a more manageable pdf file before
putting it to paper.
It's a very powerful module - does lots of things you don't need yet,
and maybe never will - and I agree that it could benefit from a
hit-the-ground-running guide...
Here's a quick-and-dirty; you can flesh out the details from the
documentation you downloaded. (By the way, you'll also want to use the
validate module - another 14 pages or so...)
======================================================
* Download configobj.py and validate.py; put them somewhere in your
Python path (or in the same folder as your project, if you want)
* Add two lines to the top of your program:
from configobj import ConfigObj
from validate import Validator
* To make working with your spec easier,
import StringIO # allows you to work with strings as if they
were files
# You could just create a spec file, and open it normally, but
this keeps everything in one place.
* Somewhere in your program, create your spec and load it. There
are a lot of ways you can do this - for me, the simple thing is to put
it in a class. I create a class called Global - it's a crutch, I
know...
class Global(object):
cfgFileName = os.getcwd() + os.sep + 'Initial.sen' #
current directory + "\" + filename - but you could put it anywhere and
call it anything
# create your spec as a multi-line string between triple
quotes
tmpStr = """
mask_file_name = string(default=None)
gray_scale = boolean(default=True)
post_event_stack = boolean(default=False)
post_event_format = string(default="Tiff 2")
show_real_time = boolean(default=False)
hourly_rate = integer(min=0, default=0)
slowdown= integer(min=0, max=10, default=1) # I don't know
what this value is/does, so this is probably wrong
start_time = string(default="00:00:00") # or you could make
the default None?
stop_time = string(default="00:00:00")
lat = float(min=0.0, max=90.0) # I have no idea what you'd
want as a default latitude, if any...
"""
cfgSpec = StringIO.StringIO(tmpStr) # turns the above
string into a file-like object, which ConfigObj is expecting
cfgFile = ConfigObj(cfgFileName,
configspec=cfgSpec, raise_errors=True,
write_empty_values=True,
create_empty=True, indent_type=' ',
list_values=True) # creates the actual ConfigObj object
vtor = Validator() # creates a validator to match your
config data against your spec
* Invoke the above code when your program starts - I do it just
before my mainloop, like so:
def main(argv=None):
if argv is None:
argv = sys.argv
test = Global.cfgFile.validate(Global.vtor, copy=True) #
tries to load cfgFile; if it doesn't exist, creates it; fills in
defaults for any missing values
Global.cfgFile.write() # saves the validated file (you
don't need to do this here at the start, but I usually do)
app = MyApp(0)
app.MainLoop()
if __name__ == '__main__':
main()
* Your ConfigObj is ready to use! Simply access the contents like
a regular dictionary. To save back to the file, call the write()
method.
Global.cfgFile['mask_file_name'] = 'bogus.txt'
Global.cfgFile.write()
maskFile = Global.cfgFile['mask_file_name']
* Or use the values directly without copying to intermediate
variables:
with open(Global.cfgFile['mask_file_name'], 'w+b') as maskFile:
maskFile.write('some bogus text')
======================================================
I'm attaching that as a text file too - I suspect that my indentation
won't survive the trip...
My Global class is an ugly hack. I'm sure you'll come up with
something more aesthetically pleasing...
--
www.fsrtechnologies.com
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--
Wayne Watson (Watson Adventures, Prop., Nevada City, CA)
(121.01 Deg. W, 39.26 Deg. N) GMT-8 hr std. time)
"Nature, to be commanded, must be obeyed."
-- Sir Francis Bacon
Web Page: <www.speckledwithstars.net/>
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