Db tests

[rajiqxf2]

Added following unit tests to validate newsletter db

1. tests to validate newsletter db schemas
2. tests to validate pre-defined article categories
3. tests to validate all table names

Context of the work

• Firstly , I tried using sqlalchemy's metadata to verify table schemas . It did not fit because unit test assertion fails to validate schema objects .Unittests assertion validates object references instead of values and Fails .

• Next solution is to try sqlalchemy's inspect which worked with some work around and here also list assertion Fails at type comparision [{'type':INTEGER}] , so I converted list to string for assertion to work as it is expected

Note: test_db has been binded and created to store expected db models to compare with actual newsletter db models , I chose to create test_db instead of storing expected db objects into variables as I thought its easy to read and maintain test_db for any updates required in the future

[sravantit25]

@mohanqxf2 I believe the required information is present to do the review. Please complete your review and assign the PR back to me.

[mohanqxf2]

pardon me @rajiqxf2 @sravantit25 I missed the notification. here are my observations.
the tests look good, Initially, i was having issues with running the tests, later figured out qa_db database need to be created, before running the db_tests.py
I created a setup on my local and ran the tests, all tests passed.

• Please update the readme file.

[sravantit25]

@rajiqxf2 I am really very sorry for holding this for so long. Please go ahead to merge it.

[qxf2]

@rajiqxf2 - can you please resolve conflicts here and send to me? It looks easy enough because the conflicts are in one file only.