Add support for session backend

[kimminw00]

Willingness to contribute

No. I cannot contribute this feature at this time.

Proposal Summary

Currently, MLflow does not support a session backend, making it difficult to maintain a consistent user session across multiple MLflow instances deployed for traffic distribution. Without session persistence, users experience the inconvenience of repeatedly re-entering session information, which reduces efficiency in a distributed environment.

Reference https://github.com/apache/airflow/blob/c1bd9c5c0141ec8b981e12232224ee1595cb83d1/airflow/www/session.py

Motivation

What is the use case for this feature?

Why is this use case valuable to support for MLflow users in general?

Why is this use case valuable to support for your project(s) or organization?

Why is it currently difficult to achieve this use case?

Details

No response

What component(s) does this bug affect?

• [ ] area/artifacts: Artifact stores and artifact logging
• [ ] area/build: Build and test infrastructure for MLflow
• [ ] area/deployments: MLflow Deployments client APIs, server, and third-party Deployments integrations
• [ ] area/docs: MLflow documentation pages
• [ ] area/examples: Example code
• [ ] area/model-registry: Model Registry service, APIs, and the fluent client calls for Model Registry
• [ ] area/models: MLmodel format, model serialization/deserialization, flavors
• [ ] area/recipes: Recipes, Recipe APIs, Recipe configs, Recipe Templates
• [ ] area/projects: MLproject format, project running backends
• [ ] area/scoring: MLflow Model server, model deployment tools, Spark UDFs
• [X] area/server-infra: MLflow Tracking server backend
• [ ] area/tracking: Tracking Service, tracking client APIs, autologging

What interface(s) does this bug affect?

• [ ] area/uiux: Front-end, user experience, plotting, JavaScript, JavaScript dev server
• [ ] area/docker: Docker use across MLflow's components, such as MLflow Projects and MLflow Models
• [ ] area/sqlalchemy: Use of SQLAlchemy in the Tracking Service or Model Registry
• [ ] area/windows: Windows support

What language(s) does this bug affect?

• [ ] language/r: R APIs and clients
• [ ] language/java: Java APIs and clients
• [ ] language/new: Proposals for new client languages

What integration(s) does this bug affect?

• [ ] integrations/azure: Azure and Azure ML integrations
• [ ] integrations/sagemaker: SageMaker integrations
• [ ] integrations/databricks: Databricks integrations

[harupy]

@kimminw00 Thanks for the FR. I'll look into https://github.com/apache/airflow/pull/21478 to see how Airflow uses Flask-Session.