Python MySQL TypeError：必须是str，而不是元组

Question

I have the following code which connects to a MySQL DB and checks which records are marked as 'active' by a field that has '1' in.

The code then downloads some files using the contents of the vulntype field in the URL for the download.

I think the issue lies with the MySQL query or the for loop to do the downloads.

The code is:-

import requests
import os
import MySQLdb
from hurry.filesize import size, si
import logging
import logging.handlers
from logging.config import fileConfig

logging.handlers = logging.handlers
fileConfig('data/logging_config.ini')
logger = logging.getLogger("downloader")


active_vuln_type = None


def get_active_vuln_sets():

    global active_vuln_type
    try:
        logging.info('Connecting to the database...')
        active_vuln_type = con = MySQLdb.connect(*******)
        logging.info('Database connected!')
    except FileNotFoundError as fnf:
        logging.error(fnf)
    except MySQLdb.Error as e:
        logging.error(e)
    try:
        logging.info('Getting active vulnerability sets...')
        cur = con.cursor()
        active = "1"
        cur.execute("""SELECT vulntype FROM vuln_sets WHERE active = %s""", (active))
        active_vuln_type = cur.fetchall()
    except MySQLdb.Error as e:
        logging.exception(e)


def download():
    try:
        logging.info('Downloading vulnerability set files...')
        for x in active_vuln_type:
            basepath = os.path.dirname(__file__)
            filepath = os.path.abspath(os.path.join(basepath, ".."))
            response = requests.get('https://vulners.com/api/'
                                    'v3/archive/collection/?type=' + x)
            with open(filepath + '/vuln_files/' + x + '.zip', 'wb') as f:
                f.write(response.content)
            filesize = size(os.path.getsize
                            (filepath + '/vuln_files/'
                             + x + '.zip'), system=si)
            files = x + ".zip - " + str(filesize)
            logging.info('Downloaded ' + x + '.zip Successfully')
            logging.info('File details: ' + files)
    except Exception as e:
        logging.exception(e)

The traceback for this is:-

Traceback (most recent call last):
  File "/home/luke/projects/vuln_backend/vuln_backend/download.py", line 61, in download
    'v3/archive/collection/?type=' + x)
TypeError: must be str, not tuple

Answer 1

active_vuln_type = cur.fetchall()

This line returns a list of rows from the database. Each row is a tuple. Of course you're only selecting one column from the table, but the interface is the same: each row is a tuple, one value per column.

for x in active_vuln_type:

Here x is a tuple like ("vulnerability of some kind",) ; note the trailing comma. You need to unpack it:

for db_row in active_vuln_type:
    x = db_row[0]  # The first and column in the row.

Besides that, please consider naming x descriptively, returning active_vuln_type from one procedure and passing it to the other as a parameter. This will make your code less brittle and easier to test.

def get_active_vuln_sets(db_host, db_user, db_password):
   # Do your stuff, using the db credentials....
   return active_vuln_type

def download(active_vuln_type):
   # Same source as now.

Now you can download(get_active_vuln_sets('192.168.100.1', 'joe', 'secret'))

Or you can test / retry the same thing without touching the DB: download([("CVE-xyxxy",), ("CVE-asdfghjkl",)]) .

One more thing you can do is to return a clean list of vuln names, not raw DB tuples:

def get_active_vuln_sets(...):
    # .....
    return [x[0] for x in cur.fetchall()]

Now the value returned will be a list of single, directly usable values, so your original download(...) code would work with it.

Answer 2

What you get it's a tuple, so you will need to get the first element with x[0]

def download():
    try:
        logging.info('Downloading vulnerability set files...')
        for x in active_vuln_type:
            basepath = os.path.dirname(__file__)
            filepath = os.path.abspath(os.path.join(basepath, ".."))
            response = requests.get('https://vulners.com/api/'
                                    'v3/archive/collection/?type=' + x[0])
            with open(filepath + '/vuln_files/' + x[0] + '.zip', 'wb') as f:
                f.write(response.content)
            filesize = size(os.path.getsize
                            (filepath + '/vuln_files/'
                             + x[0] + '.zip'), system=si)
            files = x[0] + ".zip - " + str(filesize)
            logging.info('Downloaded ' + x[0] + '.zip Successfully')
            logging.info('File details: ' + files)
    except Exception as e:
        logging.exception(e)

Answer 3

Reasons to avoid these types of errors: like you have to use try: and except function as I know.

Fetching the data using another source may not be the exect you want. Is your MySQL DB getting typeerror? Do check which records are marked as 'active' by a field that has '1' in by filtering them.

str(function(argument))

And it such likes:

try:
print(x)
except TypeError:
print("Variable x is not defined")
except:
print("Something else went wrong")

And that's all you can pass out your variable by replacing.

I do not think it will work perfectly that you want? But according to wholeblog have to understand the whole code.

If the statement of if and else works then they will pass out some results.

Thank you.