Generates a db user and adds it to `--db` as member. (CouchDB, Python3, `os.environ.get()`)

make_db_usr.py

#! /usr/bin/python3

import os
import json
import requests
import argparse
from requests.auth import HTTPBasicAuth

parser = argparse.ArgumentParser()
parser.add_argument("--srv", type=str, nargs=1,
                            help="name of the server (default is localhost)")
parser.add_argument("--port", type=str, nargs=1,
                            help="port of the server (default is 5984)")
parser.add_argument("--db", type=str, nargs=1,
                            help="name of the database (default is test_db)")
args = parser.parse_args()
if args.srv:
    srv = args.srv[0]
else:
    srv = "localhost"
if args.port:
    port = args.port[0]
else:
    port = 5984
if args.db:
    db_name = args.db[0]
else:
    db_name = "test_db"

## read from env
db_usr_name = os.environ.get('cal_usr')
db_usr_pwd = os.environ.get('cal_pwd')
db_admin_name = os.environ.get('admin_usr')
db_pwd = os.environ.get('admin_pwd')

## build data and url
db = "http://{}:{}".format(srv, port)
usr_id = "org.couchdb.user:{usr}".format(usr=db_usr_name)
d_url = "{db}/_users/{id}".format(db=db, id=usr_id)
d_data = {"name": db_usr_name,
          "password": db_usr_pwd,
          "roles": [],
          "type": "user"
}
s_url = "{db}/{db_name}/_security".format(db=db, db_name=db_name)
s_data = {"members":
          {"names":[db_usr_name],
           "roles":[]}}

## go
print("generate usr {}".format(db_usr_name))
req = requests.get(d_url, auth=HTTPBasicAuth(db_admin_name, db_pwd))
rev = req.json().get("_rev")
if  rev is not None:
    d_data["_rev"] = rev

req = requests.put(d_url, data=json.dumps(d_data), auth=HTTPBasicAuth(db_admin_name, db_pwd))
print(req.json())

req = requests.put(s_url, data=json.dumps(s_data), auth=HTTPBasicAuth(db_admin_name, db_pwd))
print(req.json())

./make_db_usr.py --help
usage: make_db_usr.py [-h] [--srv SRV] [--port PORT] [--db DB]

optional arguments:
  -h, --help   show this help message and exit
  --srv SRV    name of the server (default is localhost)
  --port PORT  port of the server (default is 5984)
  --db DB      name of the database (default is test_db)