Add Action Route for Hold For Later

[yjjw]

As a user I need to have a way to save an item in my shopping cart So that I can purchase them in the future not now

Details and Assumptions

• Using the verb PUT with the URI ~shopcarts/{user_id}/items/{item_id}/hold~ shopcarts//items//hold [EDIT]
• that item in that shopcart will be held (won't be ordered when user checks out the shopcart);
• return 200 OK upon success
• ~if the user_id or item_id is invalid (not non-negative integers), return 400 BAD_REQUEST~ [EDIT]
• ~If the user id or item_id are valid but do not exist, return 404 not found error~ [EDIT]
• Add new column to database model, a boolean flag to indicate whether that shopcart-item entry has been held
  • Need to refactor into Flask-X/swagger (including creating a new swagger data model now that we have this extra hold column, and add swagger docs to the route) [EDIT]
• BELOW are done automatically if we refactor using Flask-RESTX first

• Need to update functions accordingly like serialize() and deserialize(), make sure GET POST PUT etc. all work with this new column

  Acceptance Criteria

  Given we have item_id 100 in user_id 300
  When we call PUT on shopcarts/300/items/100/hold
  Then we receive 200 OK 
  When we call PUT on shopcarts/300/items/true/hold
  Then we receive 404 Not Found