DoodleChat

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Submission for CHALLENGE.md

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Running

Ensure ports 8888 (for backend) and 3000 (for frontend) aren't already in use. Else, modify docker-compose.yml accordingly to use another port.

$ git clone --depth 1 https://github.com/seanick39/doodlechat.git
$ cd doodlechat
$ docker compose up

Open http://localhost:3000 in browser.

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Docker compose orchestration

Database

• Compose service db
• Postgres 15 image
• Exposes port 5432 on the internal network.
• Doesn't use volume mounts. Data will not persist after container is destroyed.

Backend

• Compose service backend
• Builds and runs a Spring Boot jar
• Exposes port 8888 to host, needed by browser

Frontend

• Compose service frontend
• Copies the frontend/src directory, and runs npm run start.
• Exposes port 3000 to host.

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Approach

Instead of using websockets for bi-directional communication of messages, the approach of polling for new messages has been used. The API endpoint to list all messages accepts request parameter afterMessageId, where if a valid UUID of existing message is provided, all later messages will be sent as response. The frontend keeps checking after a short interval for new messages.

Screenshot