dfs-tender-graffiti-board

This repository contains a simple application which let you add messages to a graffiti board so that every one can see them.

The application is provided in two parts. First, the backend part, which provides an API and socket endpoint through which messages can be persisted and fetched. The second part consists of a frontend application which provides a simple UI and uses the backend to create and retrieve messages.

API endpoints

You can use the /messages endpoint to fetch all messages or post a new messages.

Authorization

The messages endpoint is secured using Basic Auth with username John and password Doe.

Get messages

curl \
  -H "Authorization: Basic Sm9objpEb2U=" \
  -X GET http://localhost:8085/messages

Post message

curl \
  -d '{"author":"John Doe", "message":"Hello World"}' \
  -H "Content-Type: application/json" \
  -H "Authorization: Basic Sm9objpEb2U=" \
  -X POST http://localhost:8085/messages

Subscribe to posted messages

There is also an endpoint where you can listen to new messages using Server Sent Events.

curl \
  -H "Authorization: Basic Sm9objpEb2U=" \
  -N http://localhost:8085/messages/subscribe

WebSocket endpoint

The frontend uses WebSockets to retrieve new messages in realtime. The endpoint is exposed at /message-socket.

How to run it

Backend

Navigate to service folder first. You can then run the application using Gradle wrapper

# On Mac or Linux
./gradlew bootRun

# On Windows
./gradlew.bat bootRun

This will run the application at http://localhost:8085.

Frontend

Navigate to ui folder in order to use the following commands.

Install frontend dependencies

When you want to start it for the first time you need to install frontend dependencies first.

yarn

Afterwards you can run the app.

Run app

You can use the following command to run a local development server

yarn start

This will run the app in the development mode. Open http://localhost:3000 to view it in the browser.

Further reading

A more detailed documentation about available scripts can be found here.