giskard.rag.report.save fails if evaluate doesn't include KnowlegeBase

[gotsysdba]

Issue Type

Bug

Source

source

Giskard Library Version

2.16.0

OS Platform and Distribution

OL9

Python version

3.11

Installed python packages

No response

Current Behaviour?

Running an evaluate without knowledge_base:

report = evaluate(get_answer, testset=loaded_testset)

An attempt to save the report:

report.save("/tmp/report")

Results in:

  File "/app/.venv/lib64/python3.11/site-packages/giskard/rag/report.py", line 161, in save
    self._knowledge_base._knowledge_base_df.to_json(
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute '_knowledge_base_df'

Expected the following files to be written to /tmp:

• testset.jsonl
• report_details.json
• metrics_results.json

Maybe empty files of:

• knowledge_base.jsonl
• knowledge_base_meta.json

So that they can be load can be run on them later.

### Standalone code OR list down the steps to reproduce the issue

```shell
loaded_testset = QATestset.load("/tmp/ts/testset.jsonl")
report = evaluate(get_answer, testset=loaded_testset)
report.save("/tmp/report")

Relevant log output

/app/.venv/lib64/python3.11/site-packages/giskard/rag/report.py", line 161, in save
    self._knowledge_base._knowledge_base_df.to_json(
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute '_knowledge_base_df'