By using the Covalent APIs, given an NFT contract and chain id, fetch all token ids and prepare an array of urls that call Get External NFT Metadata to be passed into the body for the batch query endpoint.

covalent_prepare_nft_metadata_batch.py

import requests
import time
import urllib3


def check_internet(url):
    try:
        req = urllib3.PoolManager().request("GET", url)
        if str(req.status) != "500":
            if str(req.status) != "404":
                print(req.status)
            return True
        else:
            print(req.status)
            return False
    except urllib3.exceptions.HTTPError as err:
        print(err)
        return False


contract_address = "0x60f80121c31a0d46b5279700f9df786054aa5ee5"
chain_id = 1
API_KEY = "ckey_covalent_scraper"
page_number = 0
page_size = 200_000

get_token_ids_url = "https://api.covalenthq.com/v1/" + str(chain_id) + "/tokens/" + contract_address + "/nft_token_ids/"
has_more = True
start = time.time()

while has_more:
    conn = check_internet("https://api.covalenthq.com/")
    if conn is True:

        try:
            start_request_time = time.time()

            payload = {

                "key": API_KEY,
                "page-size": page_size,
                "page-number": page_number,
                "block-signed-at-asc": True
            }

            print("Getting page: " + str(page_number) + " from: " + get_token_ids_url + "....")

            raw_data = requests.get(url=get_token_ids_url, params=payload)
            data_json = raw_data.json()
            string_comma = ","
            string_builder = "["
            for item in data_json["data"]["items"]:
                token_id = item["token_id"]
                string_builder += "\"https://api.covalenthq.com/v1/" + str(chain_id) + "/tokens/" + contract_address + "/nft_metadata/" + str(token_id) + "/\""
                string_builder += string_comma
            string_builder = string_builder[:-1]
            string_builder += "]"
            print(string_builder)

            file_name = contract_address + "_" + str(page_number) + "_" + str(page_size) + "_token_ids.json"

            f = open(file_name, "w")
            f.write(string_builder)
            f.close()
            print("Wrote: " + file_name)

            has_more = bool(data_json["data"]["pagination"]["has_more"])

        except:
            print("ERR: \n" + string_builder)
            page_number = page_number - 1
            time.sleep(20)

        print("Has more: " + str(has_more))

        page_number = page_number + 1

        end = time.time()
        elapsed_time = end - start
        request_time = end - start_request_time
        print("Request time: " + str(request_time))
        print("Elapsed time: " + str(elapsed_time))

    else:
        time.sleep(30)