estimate_json_size.py

def get_entry_size(entry: Any) -> int:
    """Get the approximate size an entry will be in JSON.

    Notes: Doesn't check for escaped characters in strings, so the size returned
    will essentially always be a lower bound.

    :param entry: The entry to get the size of

    :returns: A size in bytes
    """

    size = 0

    if isinstance(entry, dict):
        size += 1  # {
        for index, key in enumerate(entry.keys()):
            value = entry[key]
            size += 1 + len(key) + 1  # Quotes
            size += 1  # Colon
            size += get_entry_size(value)
            if index < len(entry) - 1:
                size += 1  # Comma
        size += 1  # }
    elif isinstance(entry, list):
        size += 1  # [
        for index, value in enumerate(entry):
            size += get_entry_size(value)
            if index < len(entry) - 1:
                size += 2  # Comma
        size += 1  # ]
    elif isinstance(entry, str):
        size += 1  # Quote
        size += len(entry)
        size += 1  # Quote
    elif isinstance(entry, bool):
        size += 4 if entry else 5
    elif isinstance(entry, int):
        if entry == 0:
            size += 1  # Just count direct
        else:
            if entry < 0:
                entry = -entry
                size += 1  # For minus sign
            size += int(math.log10(entry) + 1)
    elif isinstance(entry, float):
        size += len(str(entry))
    else:
        raise ValueError()

    return size