# Chat Application
This is a basic Chat application developed to Jobsity Challenge
# Requirements
Develop a basic webchat application where users must log in to have access to the chat room. Users can exchange messages and send a command to the chat. Command "/stock=aapl.us" brings the current stock information for Apple, for example.
# Components
Application was divided in 3 main components:
- SignalR and Login Application -> Chat + Login features
- Stock-Bot -> Standalone bot that read information about stocks from API
- RabbitMQ -> Resposible for exchanging message from/to Stock-Bot
# How it works?
## Stock-Bot
It`s a Worker developed in ASPNET 6 that receives/sends messages from/to RabbitMQ. When a user sends a command, like "/stock=goog.us", the information is sent to the "stock_search" queue in RabbitMQ. Stock-Bot listens to this queue and queries an API to retrieve stock information. After that, bot sends the response back to RabbitMQ this time to the "chat_hub" queue.
## SignalR + Login Application
Developed with ASPNET 6, this application has SignalR to connect all the logged users in the chat room. It also manages login with Microsoft Identity.
When this application receives a command from the chat room, it sends the message to the "stock_queue". It also listens to the queue "chat_hub" to get messages from Stock-Bot. After receiving messages from the bot, the app redirects the message to the chat room via SignalR.
Simple messages (not commands) are not sent to Stock-Bot. They are received by this application and broadcasted via SignalR directly.
## RabbitMQ
Responsible for exchanging messages from Chat Room and Stock-Bot.
# How to run the app?
Application is dockerized, so the best way is using docker-compose.
Go to the root of the app in a command prompt and run:
Build the app:
docker-compose build --no-cache
Run the 3 containers:
docker-compose up
Notice that the first container to be loaded is RabbitMQ. The other 2 containers depend on it. It is normal to see errors on the prompt for the other 2 containers while RabbitMQ is loading. Those containers will be restarted automatically a few times. Everything should work fine in a few seconds.
After that, you can access the application with the address:
http://localhost:7240
App address protocol is http, not https!
# Can I run without Docker?
Yes, but it`s a little trickier.
You have to install RabbitMQ on your localhost with default user and pass (guest/guest). It listens on the port 5672 (default).
After it is running, you need to change the "Hostname" address in 3 different parts of the ASPNET apps:
**Stock-Bot app:**
- Open the file Worker.cs and change the Hostname from "rabbit_server" to "localhost"
**Signal-R Chat app:**
- Open the file ChatHub.cs and change the hostname on the method "SendMassageToStockWorker"
- Open the file ChatWorker.cs and change the hostname on the method "ExecuteAsync"
Application components should be started in the following order:
1) RabbitMQ (you should wait a few seconds so it loads completely)
2) Stock-Bot
3) Signal-R
If stock-bot or signal-r fails, probable cause is the wrong hostname.
Let me know in case of doubts / problems
## How to use the application?
App is separated in 3 parts: Register, Login and Chat Room.
You should first Register your user. After that you will be redirected to log in. After Log in, you can start sending your messages on chat room.
If you try to access chat room without being logged in, you will be redirected.
Data inserted on register and login forms are not validated at all due time constraints. So make sure to insert pristine data on it.
# Features
Completed:
1) User login
2) Send command via chat
3) Decoupled bot API (stock-bot)
4) Bot sends custom message to chat
5) Messages ordered by timestamp**
Not completed:
1) Unit test
Bonus completed:
1) Microsoft Identity used for the login functionality
2) Wrong stock symbols by the bot causes a friendly error message to be returned
3) Build an installer (docker-compose)
Notes:
For user registration, I use InMemory database, so I don't have to setup a new component (real database).
** Chat messages are not persisted. They are real-time messages only. User can see 50 messages at most. There`s a logic on front-end to remove older messages from the list.
# Technical Debts / Improvements
Due time restriction I was not able to introduce features I'd like, such as:
- Storing chat messages in a real DB
- Storing users in real DB instead of InMemory
- Refactoring ASPNET app code in order add patterns such as Repository
- Grab connection string information from ConfigurationManager instead of hardcoding
- Insert data validation on all html fields
- More attention to secure information such as password encryption
- Using SOLID concepts widely
Welington