Echo At Time

/echoAtTime - receives two parameters, time and message, and writes that message to the server console at the given time.

Install

npm i

Usage

Start server:

REDIS_URL=redis://localhost:6379 PORT=3000 npm start

Send time in ISO format (new Date().toISOString()) and message in json format:

curl localhost:3000/echoAtTime -X POST -d '{"time": "2019-09-04T20:07:33.455Z", "message": "hello worlds"}'

Decisions

• A couple messages can be passed with the same time, so time field always modified with a suffix of a form time^i, where i is a counter.

• To represent time and message data Hashes redis data type was chosen, because of usage conviniance and speed.

• To write the message at the given time setTimeout used with a subtraction result between given and current time. This solution isn't perfect, but it is the best we can achive using built-in JavaScript functions.