Configuration variables cleanup

[shaidar]

We are working on managing Micromasters Heroku configuration variables through Saltstack similar to how we manage those for the other apps. When looking through the different envs (CI, RC, and Production) and searching through settings.py, the keys below came into question. It would be great if someone can confirm whether those keys can be removed:

• ELASTICSEARCH_DEFAULT_PAGE_SIZE
• ELASTICSEARCH_HTTP_AUTH
• ELASTICSEARCH_INDEX
• ELASTICSEARCH_SHARD_COUNT
• ELASTICSEARCH_URL
• EXAMS_AUDIT_AWS_ACCESS_KEY_ID
• EXAMS_AUDIT_AWS_SECRET_ACCESS_KEY
• EXAMS_AUDIT_ENABLED
• EXAMS_AUDIT_ENCRYPTION_FINGERPRINT
• EXAMS_AUDIT_ENCRYPTION_PUBLIC_KEY
• EXAMS_SSO_CLIENT_CODE
• EXAMS_SSO_PASSPHRASE
• EXAMS_SSO_URL
• FEATURE_ENABLE_EDX_EXAMS
• FEATURE_ENABLE_PROGRAM_LETTER
• FEATURE_MITXONLINE_LOGIN
• FEATURE_PEARSON_EXAMS_SYNC
• FEATURE_TURN_PAYMENT_OFF
• FEATURE_USE_COMBINED_FINAL_GRADE
• MICROMASTERS_ECOMMERCE_EMAIL

[shaidar]

Anna verified that the checked off FEATURES above are no longer needed.

[arslanashraf7]

My initial thought:

I think all the config keys related to Elastic Search might not have been used now since we have migrated from Elastic Search to Open Search recently.

Specifically looked briefly at the settings file changes there, we have removed these from the settings in the code and I don't see their usage in the code anymore which makes sense.

[pdpinch]

@rhysyngsun can you take a look at this? I think all _EXAMS_ settings are moot now that we're not working with Pearson any more.

[rhysyngsun]

The EXAMS settings don't appear to provide any functionality right now based on a quick code read, but there are still some lingering definitions of them in the code. Just to be sure nothing breaks, those should probably be removed although I don't think anything would break.

[rhysyngsun]

Still used

• FEATURE_MITXONLINE_LOGIN
• FEATURE_ENABLE_PROGRAM_LETTER
• MICROMASTERS_ECOMMERCE_EMAIL

Can be removed

• FEATURE_PEARSON_EXAMS_SYNC

[pdpinch]

I wrote an issue for removing the lingering code for the EXAMS settings, #5314

[shaidar]

@annagav Does the latest PR of yours mean we can remove all the EXAMS_* settings from the Heroku configuration variables listed above?