Limiting the local filesystem to a single directory and readonly in memory.

[paulheg]

Hi,

im currently using duckdb as a in memory database to query .parquet files from a local directory.
To increase the security I wanted to configure the following things:

1. Limiting the file access to a single directory.
   • I found the filesystem api: for example SET disabled_filesystems = 'LocalFileSystem';, which according to Exposing filesystem interface #200 is not exposed.
   • With the DirFileSystem it maybe is possible to specify the directory.
2. Disable write access in general
   • using access_mode=READ_ONLY but then I get the error: Catalog Error: Cannot launch in-memory database in read-only mode
   • I created a dummy.db to open in readonly, but this did not disable file writing.
   • I found the option enable_external_access the problem with this is, I want to enable read only an not disable both reading and writing.

Can anyone guide me on how to achieve this?
Maybe I can create an empty database file and then fix the read only issue?

Best regards
Paul