Os Environment Variables and LLM Calls Should be Mocked for Tests

[igooch]

What happened?

When running pytest -v in a local virtualenv on the test_main.py files:

• genai_api/src/test_main.py fails when running pytest because the OS environment variables are not in place.
• api/vertex_*/src/test_main.py fail when running pytest because there is no mock for Google_Cloud_GenAI, so the test tries to connect to a real project and call a LLM in that project.
• api/vertex_*/src/test_main.py do not have the correct expected_response since they return a single text string response.text and not a json object {'mocked_key': 'mocked_value'}.

What you expected to happen:

Running the unit tests should not require setting up environment variables or calls to an external service.

How to reproduce it (as minimally and precisely as possible):

For the genai_api test:

1. Create and activate a python virtual environment
2. Run pytest in (myvirtualenv) me@me:~/GenAI-quickstart/genai/api/genai_api/src$ pytest -v

For example on the vertex_chat_api test:

1. Create and activate a python virtual environment
2. Run pytest in (myvirtualenv) me@me:~/GenAI-quickstart/genai/api/vertex_chat_api/src$ pytest -v (you'll notice this fails with warning that the 403 Vertex AI API has not been used in project)
3. Change project_id_response.text to the name of your Google Cloud Project. https://github.com/googleforgames/GenAI-quickstart/blob/205ba78aa65782f00a8654e31c88efdc4fdaded6/genai/api/vertex_chat_api/src/main.py#L45
4. Run pytest again in (myvirtualenv) me@me:~/GenAI-quickstart/genai/api/vertex_chat_api/src$ pytest -v. Now the test fails with AssertionError: assert 'test response' == {'mocked_key': 'mocked_value'}.

Anything else we need to know?:

The value test response is coming from the actual call to the LLM. If you run the GenAI Quickstart cluster and navigate to the http://${EXT_IP}/genai_docs (following instructions on the main readme) and enter the same payload prompt as the test "prompt": "test prompt", the response is test response.