在 Python 中解码一列 Base64 字符串

Question

Situation: I have a column that I'll be extracting from SQL with hundreds of thousands of Base 64 strings that I would like to decode.

One decoded string looks like this:

b'{"a":1,"b":2,"c":3,...}'

Objective: How can I simply extract the value of the first dictionary. In this case, this would be 1. I would like the results to end up in a numpy array or df.

I found the following code to help me decode one string but unsure how to use it for every row in a column.

import base64
coded_string = '''value to decode'''
base64.b64decode(coded_string)

Answer 1

Assuming your snippet is well-formed Python (although, this seems more likely to be JSON), you can use literal_eval :

from ast import literal_eval
from base64 import b64decode
from pprint import pprint

binary = b64decode(some_str)

lib = literal_eval(binary.decode('utf8'))
pprint(lib)