The project implements a simple chat system including

• user registry service (HTTP REST API)
• client app supporting HTTP, UDP or WEBSOCKET

Powered by Ktor

The service supports the following interface:

• User registration

  POST /v1/users
  { "user" : "<name>", "address" : { "protocol" : "<HTTP | WEBSOCKET | UDP>", "host": "<host or ip>", "port": "<port>" } }
  

  If sucessful return 200 OK

  { "status" : "ok" } 
  

  If the user already exists - 409 Conflict Username must not be empty and should consist of [a-zA-Z0-9-_.]. Invalid username returns - 400 Bad Request

• User update

  PUT /v1/users/{user}
  { "protocol" : "<HTTP | WEBSOCKET | UDP>", "host": "<host or ip>", "port": "<port>" }
  

  On success return 200 OK

  { "status" : "ok" }     
  

  If the user does not exist - create a new one

  Username must not be empty and should consist of [a-zA-Z0-9-_.]. Invalid username returns - 400 Bad Request

• Retreiving the user list

  GET /v1/users/
  

  On success returns 200 OK. Example:

  {
    "ws1" : {
      "protocol" : "WEBSOCKET",
      "host" : "127.0.0.1",
      "port" : 8083
    },
    "udp2" : {
      "protocol" : "UDP",
      "host" : "127.0.0.1",
      "port" : 3002
    },
    "http1" : {
      "protocol" : "HTTP",
      "host" : "127.0.0.1",
      "port" : 8080
    }
  }
  

• Deleting a user

  DELETE /v1/users/{user}
  

  On success return 200 OK

  { "status" : "ok" }     
  

By default the user data is stored in-memory, this can be changed to store data in an SQL database by changing config file (example in DOC.md)

./gradlew :registry:test to run server tests

./gradlew :client:test to run client app tests

Note: every 3 minutes /v1/health is queried. Clients not responding 3 times in a row are automatically deleted

CLI chat with the following commands

• :update - Update the available user list quering the registry
• :user <user> - Choose a user for sending messages
• <text> - Send a message to the selected user Error, if user isn't found
• :exit - Exit, deleting the client from the register