Error in SQL editor with slashes in schema name

[yciabaud]

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.

When using Superset with a PrestoDB database to connect Apache Pulsar SQL worker, errors are occurring when working with a schema containing slashes.

I am able to query data corectly but the UI is broken.

Sample query: select * from pulsar."public/default".generator_test limit 10;

Superset version

I am using Superset version 0.28.1 in Kubernetes using helm.

Expected results

I should be able to list tables from a schema containing slashes.

Actual results

An AJAX request is made to /superset/tables/2/public/default/undefined/ and finishes with status 404.
The UI displays an error message: Error while fetching table list

Steps to reproduce

• Create a database with slashes in schema names (using pulsar for instance)
• Add this database to Superset
• Go to SQL editor and select a schema containing slashes in the select box

[villebro]

I was able to get this working, with slashes in both the table name and schema, but it was slightly more involved than I expected. The problem is that SQL Lab makes most calls with the parameters in the path, and for some reason escaped slashes (%2f) are converted to real slashes by most webservers (a security issue of some sort I believe). For table names this had been worked around by using the path: prefix in the Flask routing, but this doesn't work when there are multiple parameters with slashes (both table and schema in this case). A workaround I found for this was to perform escaping twice in the frontend (/ turns into %2f which turns into %252f), and then unescaping them twice in the backend. Anyway, I'll see if there's a better way to do this or clean up the code as much as possible and put in a PR when finished.

[yciabaud]

OK thank you @villebro , let me know if you need some assistance from me.