# Buggy code
def admin():
    configForm = forms.ConfigForm()
    configItems = current_app.config
    if configForm.validate_on_submit():
        for fieldname, fieldvalue in configForm.data.items():
            if fieldname.upper() in ["SUBMIT", "CSRF_TOKEN"]:
                continue
            # if we've got a new elasticsearch address, update our current handle to elastic
            if (
                fieldname.upper() == "ELASTICSEARCH_URL"
                and fieldvalue != current_app.config["ELASTICSEARCH_URL"]
            ):
                current_app.elastic = Elastic(fieldvalue)
            current_app.config[fieldname.upper()] = fieldvalue
            confitem = ConfigItem.query.filter_by(name=fieldname.upper()).first()
            confitem.value = str(fieldvalue)
            db.session.add(confitem)
        db.session.commit()
    return render_template(
        "admin/index.html", configForm=configForm, configItems=configItems
    )


# Traceback (TypeError)
Nov 05 17:22:50 natlas-server bash[10026]: [2019-11-05 17:22:50,681] ERROR in app: Exception on /api/getwork [GET]
Nov 05 17:22:50 natlas-server bash[10026]: Traceback (most recent call last):
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/venv/lib/python3.6/site-packages/flask/app.py", line 2292, in wsgi_app
Nov 05 17:22:50 natlas-server bash[10026]:     response = self.full_dispatch_request()
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/venv/lib/python3.6/site-packages/flask/app.py", line 1815, in full_dispatch_request
Nov 05 17:22:50 natlas-server bash[10026]:     rv = self.handle_user_exception(e)
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/venv/lib/python3.6/site-packages/flask/app.py", line 1718, in handle_user_exception
Nov 05 17:22:50 natlas-server bash[10026]:     reraise(exc_type, exc_value, tb)
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/venv/lib/python3.6/site-packages/flask/_compat.py", line 35, in reraise
Nov 05 17:22:50 natlas-server bash[10026]:     raise value
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/venv/lib/python3.6/site-packages/flask/app.py", line 1813, in full_dispatch_request
Nov 05 17:22:50 natlas-server bash[10026]:     rv = self.dispatch_request()
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/venv/lib/python3.6/site-packages/flask/app.py", line 1799, in dispatch_request
Nov 05 17:22:50 natlas-server bash[10026]:     return self.view_functions[rule.endpoint](**req.view_args)
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/app/auth/wrappers.py", line 41, in decorated_function
Nov 05 17:22:50 natlas-server bash[10026]:     return f(*args, **kwargs)
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/app/api/routes.py", line 70, in getwork
Nov 05 17:22:50 natlas-server bash[10026]:     count, context = current_app.elastic.gethost_scan_id(rand)
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/app/elastic.py", line 238, in gethost_scan_id
Nov 05 17:22:50 natlas-server bash[10026]:     if not self.checkStatus():
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/app/elastic.py", line 60, in checkStatus
Nov 05 17:22:50 natlas-server bash[10026]:     if not self.attemptReconnect():
Nov 05 17:22:50 natlas-server bash[10026]:   File "/opt/natlas/natlas-server/app/elastic.py", line 43, in attemptReconnect
Nov 05 17:22:50 natlas-server bash[10026]:     delta = now - self.lastReconnectAttempt
Nov 05 17:22:50 natlas-server bash[10026]: TypeError: unsupported operand type(s) for -: 'datetime.datetime' and 'NoneType

# Fixed code
def admin():
    configForm = forms.ConfigForm()
    configItems = current_app.config
    if configForm.validate_on_submit():
        for fieldname, fieldvalue in configForm.data.items():
            if fieldname.upper() in ["SUBMIT", "CSRF_TOKEN"]:
                continue
            current_app.config[fieldname.upper()] = fieldvalue
            confitem = ConfigItem.query.filter_by(name=fieldname.upper()).first()
            confitem.value = str(fieldvalue)
            db.session.add(confitem)
        db.session.commit()
    return render_template(
        "admin/index.html", configForm=configForm, configItems=configItems
    )