Docker-compose instructions don't work

Description

I’m trying to spin up a local instance of Rocket Chat, to work on a new project. The instructions for getting up and running with docker-compose don’t work for me.

Here’s what’s happened so far:

curl -L https://raw.githubusercontent.com/RocketChat/Docker.Official.Image/master/compose.yml -o docker-compose.yml

docker-compose up

No matter how much I fiddle with the config, I can’t get the Rocket Chat server to connect to mongo. It always results in MongoServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017