#167190540 Implement Follow And Unfollow User Feature

[henryade]

What does this PR do?

It allows users to follow and unfollow other users, get all followers and get all users they follow.

Description of Task proposed in this pull request?

• create user follower model
• create follow user route
• create unfollow user route
• create get followers route
• create get followings route
• write end to end test on all route
• write model unit tests

How should this be manually tested (Quality Assurance)?

• clone repo and checkout to this branch
• signup two users and copy the first users token and the second user's username

To Follow

• run POST /api/v1/profiles/{username}/followadd the first users token to the authorization header

To get All followers

• run GET /api/v1/profiles/followers add the first users token to the authorization header

To get All followings

• run GET /api/v1/profiles/followings add the first users token to the authorization header

To Unfollow

• run DELETE /api/v1/profiles/{username}/followadd the first users token to the authorization header

What are the relevant pivotal tracker stories?

• Story ID: #167190540

Any background context you want to add (Operations Impact)?

N/A

What I have learned working on this feature:

• I learned how to write model tests and add custom error messages to models.
• I learned how to use sequelize magic methods.

Screenshots:

User Successfully follows another user:

User Successfully unfollow another user:

Other User View All Followers:

User View All Followings:

[chialuka]

Good job.