Automating tasks with Python

Today I had to create a large number of test data entities in JSON. Instead of cutting and pasting I decided to give Python a go and therefore I created a command line script to generate the test data I needed. I had to google everything I needed, as I have only seen Python a few times before, but I ended up creating a neat little script that works perfectly, although I could have used the language features for JSON probably.

Here is the script:

__author__ = 'Per-Oivin Andersen'

import getopt, sys, uuid, string, random, os

def usage():

    print "usage: provide count and number of orgunits and the file usage.xml will be generated."

def main():

    filename = "users.json"

    try:

        opts, args = getopt.getopt(sys.argv[1:], "hc:v", ["help", "count="])

    except getopt.GetoptError as err:

        # print help information and exit:

        print(err) # will print something like "option -a not recognized"

        usage()

        sys.exit(2)

    orgCount = None

    verbose = False

    for o, a in opts:

        if o == "-v":

            verbose = True

        elif o in ("-h", "--help"):

            usage()

            sys.exit()

        elif o in ("-c", "--count"):

            orgCount = a

        else:

            assert False, "unhandled option"

    if not orgCount.isdigit:

        usage()

        sys.exit()

    if int(orgCount) <= 0:

        usage()

        sys.exit()

    json ="["

    for num in range(1,int(orgCount)+1):

        id=uuid.uuid4()

        name=''.join(random.choice(string.ascii_letters) for _ in range(6))

        username=''.join(random.choice(string.ascii_letters) for _ in range(6))

        group=str(bool(random.getrandbits(1))).lower()

        json += "{" \

                "\n\"id\": \"%s\"," \

                "\n\t\"username\": \"%s\"," \

                "\n\t\"password\": \"password\"," \

                "\n\t\"isGroup\": %s," \

                "\n\t\"name\": \"%s\"" \

                "\n}" % (id,username,group,name)

        if num < int(orgCount):

            json += ",\n"

    json += "]"

    try:

        os.remove(filename)

    except OSError:

        pass

    file = open(filename, 'w+')

    file.write(json)

    print json

    print "\n\n JSON written to file " + filename

if __name__ == "__main__":

    main()