aws_metadata_json.py

import sys
import argparse
import urllib.request
import urllib.parse
import json
from collections.abc import Mapping
from pprint import pprint
import os.path

global dict_endpoints
dict_endpoints = {}
global base_path
base_path = "http://169.254.169.254/2016-09-02/meta-data/"


if sys.version_info <= (3, 0):
    sys.stdout.write("Sorry, requires Python 3.x, not Python 2.x\n")
    sys.exit(1)


parser = argparse.ArgumentParser()
parser.add_argument(
    "-e,",
    "--endpoint",
    nargs="+",
    help="Metadata endpoint, space seperated for children and grandchildren",
    required=False,
)
args = parser.parse_args()


def remove_slashes(obj):
    if isinstance(obj, Mapping):
        return {key.replace("/", ""): remove_slashes(val) for key, val in obj.items()}
    return obj


def get_data(url):
    if isinstance(url, list):
        url = os.path.join(*url)
    url = urllib.parse.urljoin(base_path, url)
    try:
        with urllib.request.urlopen(url) as response:
            return response.read().decode("utf-8").splitlines()
    except:
        pass


def list_parser(endpoint_list):
    return [remove_slash(i) for i in endpoint_list]


def response_string(item_list):
    if len(item_list) == 1:
        return str(item_list[0])
    else:
        return item_list


endpoints = get_data(None)

def end_checker(endpoint):
    children = get_data(endpoint)
    for child in children:
        grandchild = os.path.join(endpoint, child)
        check = get_data(grandchild)
        try:
            if str(check[0]) == child:
                return True
        except:
            return False


def list_builder(endpoints):
    for endpoint in endpoints:
        children = get_data(endpoint)        
        if endpoint == "public-keys/":
            dict_endpoints[endpoint] = str(children[0])
            continue
        if end_checker(endpoint):
            dict_endpoints[endpoint] = children[0]
        else:
            for x in children:
                dict_endpoints[endpoint] = children


def paths_to_value(value, d, current_path=None):
    if current_path is None:
        current_path = []

    for k, v in d.items():
        if isinstance(v, list):
            yield current_path + [k]
        else:
            if isinstance(v, dict):
                path = current_path + [k]
                yield from paths_to_value(value, v, path)



list_builder(endpoints)

for x in paths_to_value([], dict_endpoints):
    x = str(x[0])
    dict_endpoints[x] = {}
    for item in get_data(x):
        nested_endpoint = os.path.join(x, item)
        resp = get_data(nested_endpoint)
        dict_endpoints[x][item] = str(resp[0])


dict_endpoints = (remove_slashes(dict_endpoints))


    
if args.endpoint:
    path = os.path.join(*args.endpoint)
    print(json.dumps({path:get_data(path)}))
else: 
    print(json.dumps(dict_endpoints, sort_keys=True, indent=4))

    
    
"""
Example output:
ubuntu@ip-172-31-18-225:~/source$ python3 aws_metadata_json.py
{
    "ami-id": "ami-077a5b1762a2dde35",
    "ami-launch-index": "0",
    "ami-manifest-path": "(unknown)",
    "block-device-mapping": {
        "ami": "/dev/sda1",
        "root": "/dev/sda1"
    },
    "hostname": "ip-172-31-18-225.eu-west-2.compute.internal",
    "instance-action": "none",
    "instance-id": "i-0273abcf0956d27b3",
    "instance-type": "t2.micro",
    "local-hostname": "ip-172-31-18-225.eu-west-2.compute.internal",
    "local-ipv4": "172.31.18.225",
    "mac": "06:69:99:78:86:06",
    "metrics": {
        "vhostmd": "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
    },
    "network": {
        "interfaces": "macs/"
    },
    "placement": {
        "availability-zone": "eu-west-2a"
    },
    "profile": "default-hvm",
    "public-hostname": "ec2-35-177-150-174.eu-west-2.compute.amazonaws.com",
    "public-ipv4": "35.177.150.174",
    "public-keys": "0=test",
    "reservation-id": "r-0c0a503d55aea9b4e",
    "security-groups": "launch-wizard-5",
    "services": {
        "domain": "amazonaws.com",
        "partition": "aws"
    }
}

ubuntu@ip-172-31-18-225:~/source$ python3 aws_metadata_json.py -e ami-id
{"ami-id": ["ami-077a5b1762a2dde35"]}

ubuntu@ip-172-31-18-225:~/source$ python3 aws_metadata_json.py -e block-device-mapping ami
{"block-device-mapping/ami": ["/dev/sda1"]
"""