feeds

Design

• The service layer is based on Spring Boot.
• Uses MongoDB at the datastore layer.
  I chose MongoDB because each read/write operation to the DB can be independent, we do not need transaction management in this kind of application. Users/Feeds/Articles could get added/removed independently. MongoDB allows schema-less design so content of articles can change independently. MongoDB allows eventual consistency, it's okay in this kind of application where when an article is added to Feed, the article may surface up after some time to the user.
• The REST APIs are based on HATEOAS

Entities

• Users
  • Collection name: Users

  {
    "username" : "<username>",
    "subscribed_feeds" : [ "feed1", "feed2", ... ]
  }

• Feeds
  • Collection name: Feeds

  {
    "name" : "<feedname>",
    "articles": [ { ... }, { ... } ]
  }

The MongoDB can be configured in com.bufferworks.feeds.MongoDbConfig
DB Name: feedsportal
DB Connection: localhost/27017

Compiling and running the program

• The application based on Spring Boot
• Use mvn clean package to build the source. This will also run the tests.
• This will generate a runnable jar target/feeds-0.1.jar
• To execute the program: java -jar target/feeds-0.1.jar
  Add -Dserver.port=9090 to run the server on a different port
  DB config parameters can be updated using -
  java -Dmongodb.host=localhost -Dmongodb.port=27017 -Dmongodb.database=test -jar target/feeds-0.1.jar

Using API's

• The API's are implemented following the HATEOAS paradigm where response have links to follow specifying the actions available
• Root Resource lists all sub resources, available via
  URL: http://localhost:8080/jersey/api
  Headers: Accepts: application/com.bufferworks.root+json
  
• Added Feeds.json that is a postman collection to with API requests
• All REST resources are under com.bufferworks.feeds.restapi.resource package.
• All media types for REST resources are under com.bufferworks.feeds.restapi.media package.
• MongoDB DB Services are under com.bufferworks.feeds.persist package.
• MongoDB entities are under com.bufferworks.feeds.persist.entity package.

API Resources

• UsersResource
• UserResource
• FeedsResource
• FeedResource
• ArticlesResource
• SubscriptionsResource
• UserArticlesResource

Integration for Test Resources

• ArticlesResourceIntegrationTest
• FeedResourceIntegrationTest
• FeedsResourceIntegrationTest
• SubscriptionsResourceIntegrationTest
• UserArticlesResourceIntegrationTest - This integration test creates a user, creates feeds and adds articles to the feeds. Subscribes the user to 3 feeds and then returns all articles associated with the subscribed feeds.
• UserResourceIntegrationTest
• UsersResourceIntegrationTest