Story (Required)

This issue is to investigate db integration in road-core and pick one to support as our persistent db:

currently road-cord supports postgres and redis as cache factory
https://github.com/road-core/service/blob/main/ols/src/cache/postgres_cache.py
https://github.com/road-core/service/blob/main/ols/src/cache/redis_cache.py

and can be configured via config, e.g.

postgres:
https://github.com/road-core/service/blob/3ea924f4945c0677e3ba8576161b37fb14b15075/README.md?plain=1#L422-L434

redis:
https://github.com/road-core/service/blob/3ea924f4945c0677e3ba8576161b37fb14b15075/tests/config/valid_config_redis.yaml#L14-L22

This issue is to investigate the two db configuration and pick one support in RHDH lightspeed as our database for chat history.

(can also support both, if all configuration required are same)

Background (Required)

<Describes the context or background related to this story>

will need to setup a database for implementation & testing purpose.
can to use our hardcoded database to start with

Out of scope

<Defines what is not included in this story>

db other than the one defined & supported in road-core are out of scope

Approach (Required)

<Description of the general technical path on how to achieve the goal of the story. Include details like json schema, class definitions>

Dependencies

<Describes what this story depends on. Dependent Stories and EPICs should be linked to the story.>

Acceptance Criteria (Required)

<Describe edge cases to consider when implementing the story and defining tests>

<Provides a required and minimum list of acceptance tests for this story. More is expected as the engineer implements this story>

documentation updates (design docs, release notes etc)
demo needed
SOP required
education module update (Filled by DEVHAS team only)
R&D label required (Filled by DEVHAS team only)

Done Checklist

Code is completed, reviewed, documented and checked in
Unit and integration test automation have been delivered and running cleanly in continuous integration/staging/canary environment
Continuous Delivery pipeline(s) is able to proceed with new code included
Customer facing documentation, API docs, design docs etc. are produced/updated, reviewed and published
Acceptance criteria are met
If the Grafana dashboard is updated, ensure the corresponding SOP is updated as well