Can not add or edit database

[meinnamehier]

When I try to add or edit a database, i get the error "'NoneType' object has no attribute 'encode'" and no database is added or edited.
This happens with the demo database as well as a Snowflake database.
Clicking on "Test Connection" shows success.

Expected results

The database is added to the list of sources

Actual results

An error message is displayed: 'NoneType' object has no attribute 'encode'
There is no information on the console output, loglevel is "DEBUG"

Screenshots

How to reproduce the bug

1. Go to Sources -> Database
2. Click on "Save"
3. See error

Environment

Docker container

Host Information:

• superset version: latest Master branch
• python version: 3.7.7
• node.js version: 12.8.0
• npm version: 6.11.2

Checklist

Make sure these boxes are checked before submitting your issue - thank you!

• I have checked the superset logs for python stacktraces and included it here as text if there are any.
• I have reproduced the issue with at least the latest released version of superset.
• I have checked the issue tracker for the same issue and I haven't found one similar.

Additional context

Host OS: MacOS Mojave 10.14.6
The Snowflake connection string looks like this:
snowflake://USER:xxxxxxxx@nfXXXX.eu-central-1/DATABASE/PUBLIC?warehouse=WAREHOUSE&role=PRODUCTION_USER
Snowflake-SQLalchemy is installed.

[villebro]

Thanks for the bug report @meinnamehier , I am able to reproduce, will post a bugfix shortly.

[ustinovam]

And i not add mysql database

[stale]

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