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README.md

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+# MessengerApp
+Basic messaging app to display messages over local WebSocket.
+
+## Objective
+The task was to create an android messaging application over a WebSocket. The application should be a one screen application hosting a message entry box, send button and message list hosting the conversation. The Conversation should be ordered with oldest messages at the top and newest at the bottom. 
+ - Message List and Text Entry Box
+ - Distinguish between received and sent messages
+ - Item sectioning after a break of more than 2 hours of no activity
+ - Persistent storage and observables
+ - Two-way messaging
+ - Animating message entry
+ 
+## Approach
+
+### MVVM architecture & Solid coding
+This application followed the MVVM architecture with the use of live data and observers. SOLID coding principle were followed to ensure clean code.
+
+### WebSocket with coroutines
+This uses the android kotlin native components, Coroutines, for concurrency. I used the tinder Scarlet WebSocket library, Retrofit inspired WebSocket client, to simply handle the WebSocket operations.
+*NB. Nearly all the resources online for tinder scarlet point towards using RxJava - this is quite unique whilst still being "out of the box"*
+
+### Room Database for storing the conversation
+Room database is a powerful tool for caching data. Room also offers the use of live data queries which seamlessly allows for displaying messages.
+
+### Trigger a random message after I send one
+Since this WebSocket was local there were no messages being received from another member. When a message is sent, by the user, after a delay of second message containing a random string is sent as another user.
+
+### Recycler view to host conversation
+I created a recycler view to host the conversation. The messages were submitted via an edit text & submit button - however pressing enter will submit the message. The message clears after it is sent. It handles messages sent, messages received and sectioning messages.
+
+### Item sectioning
+When the WebSocket is connected to the last message stored is read for its time stamp. If the duration between that timestamp and now is greater than two hours then a sectioning message is sent to the database.
+
+### Kodein dependency injection
+Simple kotlin dependency injection to seamlessly create module is application class and retrieve them via "KodeinAware" implementation.
+
+### *Bonus* Network interception
+Although this project is local but if the user is offline then messages will not be sent. With the tinder scarlet library, I used a network interceptor.
+
+## Limitation
+
+### Sent/Not Sent messages?
+It’s hard to tell if the message has been successfully sent over the WebSocket.
+
+## If I had more time
+
+### Animation presence
+Not much consideration was given to animations in this project as the requested animation was not easy to come by. If I had more time, I would have implemented animations for chat message entry and population of messages recycler view.
+
+### Sent/Not Sent messages?
+Messages to have a Boolean value of "isSent" which changes when the message is received via the WebSocket.
+
+### Online Status
+Would have a live data observer working with WebSocket connection to determine connection.
+
+### Unit tests & UI tests
+As mentioned above the scarlet/coroutines method was quite original hence it would have taken some time to create mocks/test cases.
+
+## Architectural Pattern
+
+MVVM - Model View ViewModel
+SOLID coding
+
+## Jetpack
+
+* [AndroidX](https://developer.android.com/jetpack)
+
+## Built With
+
+* [Kodein](https://github.com/Kodein-Framework/Kodein-DI) - Painless Kotlin Dependency Injection
+* [Scarlet](https://github.com/Tinder/Scarlet) - A Retrofit inspired WebSocket client for Kotlin, Java, and Android
+* [Okhttp](https://github.com/square/okhttp) - Square’s meticulous HTTP client for Java and Kotlin.
+* [Room Persistence Library](https://developer.android.com/topic/libraries/architecture/room) - The Room persistence library provides an abstraction layer over SQLite to allow for
+* [Gson](https://github.com/google/gson)- A Java serialization/deserialization library to convert Java Objects into JSON and back
+
+## Submitted by
+
+* **Haider Malik** - *Android Developer*