Passing arguments to a python blender script, through the brenda-web interface, how do I parse the arguments?

Question

It seems like an easy task, but there is a requirement that "--" is added to the command, to tell the program to pass the arguments to the script (and not process them). For example:

  $ blender -b testscene.blend --python localrender.py -- -start 1 -type diffuse -samples 100

I found a way to separate out the script arguments by using this:

try:
    args = list(reversed(sys.argv))
    idx = args.index("--")
except ValueError:
    params = []
else:
    params = args[:idx][::-1]
    print("Script params:", params)

Which breaks them all up individually. Which is not what I think needs to happen. I also have tried argparse, but I think that the "--" is breaking it. Does anybody know a complex way to parse this stuff out? I'd like to keep the arg + value together, so that I can do something like this:

args = parser.parse_args()
if args.index:
    logging.info("index set to: " + str(args.index))

But I am stuck with "blender: error: unrecognized arguments:"

EDIT----------------------------- EDIT------------------------

I am currently using this to grab the args after "--"
try:
    args = list(reversed(sys.argv))
    idx = args.index("--")
except ValueError:
    params = []
else:
    params = args[:idx][::-1]
    #print("Script params:", params)

logging.info(params)

which creates this structure: ['-items', '1', '-type', 'AO', '-samples', '100', '-size', '1024']

What should I do? I think this is going in the wrong direction, seeing as I want to group by Option:Argument. I tried this code also, but it split the actual letters in the arguments into pieces:

try:
    #getopt.getopt(sys.argv[1:], 'x:y:')
    #opts,val = getopt.getopt(params,"hi:o:",["objindex="])
    opts, args = getopt.getopt(params, "h:o")
except getopt.GetoptError:
    logging.info('prototype.py --items <items>')
    sys.exit(2)

logging.info("params:")
logging.info(params)
logging.info("opts")
logging.info(opts)

exit()

for opt, val in opts:
 # print("option" + opt)
  if opt in ("--items", "-items"):
    objindex = val
  elif opt in ("--type", "-type"):
    logging.info("found render type: " + val)

Answer 1

You can make your own parser, by using iterators. This code will seperate your arguments into two dicts (before and after the -- ):

args = '-b testscene.blend --python localrender.py -- -start 1 -type diffuse -samples 100'
iter = (i for i in args.split(' '))

args_dict = {'part1': {}, 'part2': {}}
current_part = 'part1'
for chunk in iter:
    if chunk == '--':
        current_part = 'part2'
        continue
    if chunk.startswith('-'):
        args_dict[current_part][chunk.lstrip('-')] = next(iter)

print(args_dict)

Output:

{'part1': {'b': 'testscene.blend', 'python': 'localrender.py'},
 'part2': {'samples': '100', 'start': '1', 'type': 'diffuse'}}

I'm not really sure what you're trying to do with these arguments though, please clarify your question if you want more help.