Fixing 'certificate Verify Failed' In Python Requests

Hey everyone! Have you ever run into the dreaded [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: certificate has expired error while using Python's requests library? It's a real head-scratcher, but don't worry, it's pretty common. Basically, it means your Python script is having trouble verifying the SSL certificate of the website you're trying to connect to. This often happens because the certificate has expired, is not trusted, or there's some other issue preventing a secure connection. Let's dive into what this error means, why it happens, and how to fix it.

Understanding the certificate verify failed Error

So, what's going on when you see this error? Think of SSL certificates as digital passports for websites. When your browser or Python script connects to a website using HTTPS (the secure version of HTTP), it checks the website's certificate to make sure it's valid. This certificate is issued by a trusted Certificate Authority (CA) and proves that the website is who it claims to be. The verification process involves checking several things:

• Expiration Date: Is the certificate still valid? If it's expired, you'll get this error.
• Trust: Is the certificate issued by a CA that your system trusts? If not, your system might flag it as untrusted.
• Hostname: Does the certificate match the website's domain name? If not, it could be a sign of a man-in-the-middle attack.

When the verification fails, it's usually because one of these checks didn't pass. In your case, the error message certificate has expired clearly points to an expired certificate. This means the website's security certificate is no longer valid, and your Python script is rightly refusing to connect.

Common Causes and Solutions

Let's break down the common causes and how to solve them, including the specific situation in the code snippet you provided. The error message in your code suggests that the certificate on api.boptest.net has expired. This is a server-side issue, meaning the website's administrators need to update their certificate. However, there are some things you can do on your end to try and work around it or troubleshoot the problem.

1. Update Your Python and requests Library

Make sure you have the latest versions of Python and the requests library. Older versions might have compatibility issues with newer SSL certificates. You can update your packages by running the following commands in your terminal:

python -m pip install --upgrade pip
python -m pip install --upgrade requests

2. Check the Website's Certificate Directly

Before you start messing with your code, try visiting the website in your web browser. Your browser should also flag the expired certificate, giving you more confirmation of the problem. Chrome, Firefox, and other browsers provide detailed information about the certificate, including its expiration date and issuer. This helps you confirm if the issue is indeed the certificate itself.

3. Temporarily Disable SSL Verification (Not Recommended for Production)

Warning: Disabling SSL verification is generally not recommended for production code because it makes your application vulnerable to security risks. However, if you're just testing or working on a local development environment, you can temporarily disable SSL verification. You can do this in your requests call by setting the verify parameter to False:

import requests

url = 'https://api.boptest.net/testcases/bestest_hydronic_heat_pump/select'

try:
    response = requests.post(url, verify=False)  # Disable SSL verification
    response.raise_for_status()
    data = response.json()
    print(data)
except requests.exceptions.SSLError as e:
    print(f"SSL Error: {e}")
except requests.exceptions.RequestException as e:
    print(f"Request Error: {e}")

This tells requests to skip the certificate verification. But be aware that you're opening yourself up to potential security risks. Use this method with caution and only when you fully understand the implications. Make sure to revert this change as soon as the certificate issue is resolved.

4. Specify a Custom CA Bundle (If You Trust the Certificate)

If you trust the website despite the expired certificate (maybe you're connecting to a local or internal server), you can specify a custom CA bundle that includes the certificate. This approach is safer than completely disabling verification.

• Get the Certificate: You'll need to download the website's certificate. You can usually do this from your browser. In Chrome, for example, click the padlock icon in the address bar, then click