This is a submission of the backend assignment of 2023 TikTok Tech Immersion, based upon the demo template.

The HTTP server serves as an interface for users, in which it connects with a micoservice RPC server which uses Redis database to store the messages.

Run the following command the same directory as docker-compose.yml to initialise the necessary Docker containers:

docker compose up -d

To send a message, we send a POST request to localhost:8080/api/send, specifying the following URL parameters:

• chat: Name of chat in the form [USER A]:[USER B]
• sender: Name of sender
• text: Text in message

Example To send "hi" from a to b, we use the following command:

curl -X POST 'localhost:8080/api/send?chat=a:b&sender=a&text=hi'

To send a message, we send a GET request to localhost:8080/api/pull, specifying the following URL parameters:

• chat: Name of chat in the form [USER A]:[USER B]
• cursor: Earliest epoch time of messages to retrieve, 0 by default
• limit: Maximum number of messages to retrieve, 10 by default
• reverse: Boolean value of whether to sort messages in ascending order by time

Example To retrieve all messages between a and b (i.e., chat a:b), we use the following command:

curl 'localhost:8080/api/pull?chat=a:b&cursor=0&limit=10&reverse=false'

• Although we specified cursor as 0 and limit as 10, here, we could omit them. The request will default to cursor=0 and limit=10 respectively.