[ENH]: GET /databases should return 404 instead of 500 for not found

[codetheweb]

Description of changes

When a database is not found, a 404 HTTP status code is now returned instead of a 500.

Test plan

How are these changes tested?

Added a new test. It doesn't strictly test the status code (difficult if we want to keep the more friendly error message), but exercises the code path.

Documentation Changes

Are all docstrings for user-facing APIs updated if required? Do we need to make documentation changes in the docs repository?

n/a

[github-actions]

Reviewer Checklist

Please leverage this checklist to ensure your code review is thorough before approving

Testing, Bugs, Errors, Logs, Documentation

• Can you think of any use case in which the code does not behave as intended? Have they been tested?
• Can you think of any inputs or external events that could break the code? Is user input validated and safe? Have they been tested?
• If appropriate, are there adequate property based tests?
• If appropriate, are there adequate unit tests?
• Should any logging, debugging, tracing information be added or removed?
• Are error messages user-friendly?
• Have all documentation changes needed been made?
• Have all non-obvious changes been commented?

System Compatibility

• Are there any potential impacts on other parts of the system or backward compatibility?
• Does this change intersect with any items on our roadmap, and if so, is there a plan for fitting them together?

Quality

• Is this code of a unexpectedly high quality (Readability, Modularity, Intuitiveness)

[atroyn]

I'm a bit confused by this implementation, the new error is already a ChromaError so it should be already getting caught by:

except ChromaError as e:
            raise e

Why do we need a separate exception path like

except Exception as e:
            if isinstance(e, NotFoundError):
            ...

[atroyn]

why not except NotFoundError ?

[codetheweb]

I'm a bit confused by this implementation, the new error is already a ChromaError so it should be already getting caught by:

it's just

 except Exception as e:
    if isinstance(e, NotFoundError):
        raise ValueError(
            f"Could not connect to database {database} for tenant {tenant}. Are you sure it exists?"
        )

    raise e

vs.

except NotFoundError:
  raise ValueError(
        f"Could not connect to database {database} for tenant {tenant}. Are you sure it exists?"
    )
except Exception as e:
  raise e

Functionally the same but the second one does look cleaner, so I'll change.

[atroyn]

Discussed offline, ChromaError allows us to set the message directly at the callsite by overriding message:

class ChromaError(Exception, EnforceOverrides):
    trace_id: Optional[str] = None
    def code(self) -> int:
        """Return an appropriate HTTP response code for this error"""
        return 400  # Bad Request
    def message(self) -> str:
        return ", ".join(self.args)

So let's just use that

[atroyn]

LGTM