authenticator paremeter in ChatSnowflakeCortex

[grepinsight]

Summary of Changes

This PR introduces the support for an optional authenticator parameter in the ChatSnowflakeCortex class, allowing for more flexible authentication methods when connecting to Snowflake. This is necessary to enable MFA token caching (https://docs.snowflake.com/en/user-guide/security-mfa#:~:text=to%20authenticator%20%3D-,username_password_mfa,-.)

The changes include:

1. Added snowflake_authenticator Field:

   • snowflake.py: A new field snowflake_authenticator is added to the ChatSnowflakeCortex class. This field allows specifying an authentication method such as 'snowflake', 'username_password_mfa', 'oauth', etc. It can be automatically inferred from the SNOWFLAKE_AUTHENTICATOR environment variable.

2. Connection Parameter Updates:

   • snowflake.py: The authenticator parameter is conditionally added to the Snowflake connection parameters if provided.

3. Integration Tests:

   • Tests in test_snowflake.py have been added to ensure the correct handling and precedence of the authenticator parameter both when set explicitly and as an environment variable.

4. Unit Tests:

   • Comprehensive unit tests have been added to check:
     • The correct setting of the authenticator parameter.
     • The behavior when only environment variables are used.
     • Scenarios when no authenticator is provided.
     • Handling of the authenticator alias value.