writing command-line options into file

[hiral]

For following example, how to write command-line option OR metavar
into file...

parser.add_option("-opt1", metavar="MY_OPTION1", default=123)
parser.add_option("-opt2", metavar="YOUR_OPTION2" ,default= "abc")
parser.add_option('-opt3", metavar="FLAG", default=True)

do we have any facility to write command-line option OR 'metavar' into
file as follow...

output_file:
MY_OPTION1 123
YOUR_OPTION2 abc
FLAG True

OR
output_file:
opt1 123
opt2 abc
opt3 True

Any idea?

Please note that in actual application there are about 80 to 90
command-line options.

Thank you in advance.

 

[Brian Blais]

For following example, how to write command-line option OR metavar
into file...

parser.add_option("-opt1", metavar="MY_OPTION1", default=123)
parser.add_option("-opt2", metavar="YOUR_OPTION2" ,default= "abc")
parser.add_option('-opt3", metavar="FLAG", default=True)

do we have any facility to write command-line option OR 'metavar' into
file as follow...

output_file:
MY_OPTION1 123
YOUR_OPTION2 abc
FLAG True

OR
output_file:
opt1 123
opt2 abc
opt3 True

Perhaps something like this would work. This loads and saves just the default values. A little more digging could make it more robust, and inclusive. The output file (test.yaml) looks like:

opt1: 123
opt2: abc
opt3: true



from __future__ import with_statement
from optparse import OptionParser
import yaml

class MyOptionParser(OptionParser):

def save(self,fname):
data=self.defaults
with open(fname,'w') as fid:
yaml.dump(data,fid,default_flow_style=False)

def load(self,fname):
data=yaml.load(open(fname))
for option in data:
self.add_option("--"+option,default=data[option])



parser = MyOptionParser()

parser.add_option("--opt1", metavar="MY_OPTION1", default=123)
parser.add_option("--opt2", metavar="YOUR_OPTION2" ,default= "abc")
parser.add_option("--opt3", metavar="FLAG", default=True)


parser.save('test.yaml')


newparser=MyOptionParser()
newparser.load('test.yaml')


bb

 

[Steven D'Aprano]

For following example, how to write command-line option OR metavar into
file...

parser.add_option("-opt1", metavar="MY_OPTION1", default=123)
parser.add_option("-opt2", metavar="YOUR_OPTION2" ,default= "abc")
parser.add_option('-opt3", metavar="FLAG", default=True)

What is parser?

do we have any facility to write command-line option OR 'metavar' into
file as follow...

output_file:
MY_OPTION1 123
YOUR_OPTION2 abc
FLAG True

Write a helper function like this:

def opt_writer(f, parser, *args, **kwargs):
parser.add_option(*args, **kwargs)
template = "%(metavar)s %(default)s\n"
f.write(template % kwargs)

then call it:

ofile = open('output.txt', 'w')
opt_writer(ofile, parser, "-opt1", metavar="MY_OPTION1", default=123)
opt_writer(ofile, parser, "-opt2", metavar="YOUR_OPTION2" ,default= "abc")
opt_writer(ofile, parser, "-opt3", metavar="FLAG", default=True)
ofile.close()