added certificate date check

ping_engine.py

@@ -3,6 +3,9 @@ import os
 import requests
 import datetime
 import json
+import OpenSSL
+import ssl
+import pytz
 
 app = Flask(__name__)
 
@@ -110,5 +113,30 @@ def api():
  #       time = now,
  #       status = status_string)
 
+@app.route('/certdate/<name>/')
+def cert(name):
+    apiToken = request.args.get('token')
+    now = str(datetime.datetime.now())
+    now_date=datetime.datetime.now()
+    if apiToken == token:
+        cert=ssl.get_server_certificate((name, 443))
+        x509 = OpenSSL.crypto.load_certificate(OpenSSL.crypto.FILETYPE_PEM, cert)
+        bytes=x509.get_notAfter()
+        timestamp_str = str(bytes.decode('utf-8'))
+        date_string = str(datetime.datetime.strptime(timestamp_str, '%Y%m%d%H%M%S%z'))
+        date = datetime.datetime.strptime(timestamp_str, '%Y%m%d%H%M%S%z')
+        if date.replace(tzinfo=pytz.utc) > now_date.replace(tzinfo=pytz.utc):
+            status_string = "OK"
+        else:
+            status_string = "Expired"
+    else: 
+        status_string = ' wrong token'
+        ip_addr = request.remote_addr
+        out = '%s - Unauthorized from IP: %s' %(now, ip_addr)
+        print (out)
+    return jsonify (
+        time = now,
+        date_valid = date_string,
+        status = status_string)
 if __name__ == '__main__':
     app.run(debug=True)

requirements.txt

@@ -1,2 +1,4 @@
 Flask==2.2.2
 requests==2.25.1
+pyOpenSSL==22.0.0
+pytz==2022.6