view-jwt

#!/usr/bin/env python3

import sys, os, re
import jwt
import json
import arrow
from datetime import datetime, timezone
from dateutil import tz
import pytz

def human_readable_utc_timestamp(my_timestamp):
    return datetime.utcfromtimestamp(my_timestamp).strftime('%Y-%m-%d %H:%M:%S UTC')

def human_readable_local_timestamp(my_timestamp):
    local_timezone = datetime.now(timezone.utc).astimezone().tzinfo
    local_datetime = datetime.fromtimestamp(my_timestamp, tz=pytz.utc).astimezone(local_timezone)
    return local_datetime.strftime('%Y-%m-%d %H:%M:%S %Z%z')

def decode_jwt(token):
    decoded_token = jwt.decode(token, algorithms=[], verify=False)  # Disable signature verification
    # Make timestamps more readable
    for timestamp_field in ['iat', 'nbf', 'exp']:
        if decoded_token.get(timestamp_field):
            decoded_token[timestamp_field] = human_readable_local_timestamp(decoded_token.get(timestamp_field))
    formatted_token = json.dumps(decoded_token, indent=4)
    return formatted_token

if len(sys.argv) > 1:
    for arg in sys.argv[1:]:
        # Is this argument a filename or a JWT token?
        if os.path.isfile(arg):
            # Filename. Search it for JWT token(s).
            with open(arg, 'r') as file:
                for line in file:
                    # Does this line contain a JWT token?
                    jwt_token = re.search("eyJ\S*", line)
                    if jwt_token:
                        formatted_token = decode_jwt(jwt_token.group())
                        print("Decoded token:")
                        print(formatted_token)
        else:
            # A literal JWT token provided as argument.
            jwt_token = re.search("eyJ\S*", arg)
            if jwt_token:
                formatted_token = decode_jwt(jwt_token.group())
                print("Decoded token:")
                print(formatted_token)
else:
    # No arguments provided, let's try to read from stdin.
    for line in sys.stdin:
        # Does this line contain a JWT token?
        jwt_token = re.search("eyJ\S*", line)
        if jwt_token:
            formatted_token = decode_jwt(jwt_token.group())
            print("Decoded token:")
            print(formatted_token)