Adding port to docker run command

[james-beston]

I was having trouble accessing the Docker image on my Mac as the port (27017) was not bound when I ran the command in the instructions:

docker run --name some-mongo -d mongo:tag

Suggest updating instructions to:

docker run -dp 27017:27017 --name some-mongo -d mongo:tag

With the updated code I could run mongosh without the connection being refused

[wglambert]

Port exposure isn't exclusive to this image, so reproducing Docker's docs could make each image's documentation unnecessarily verbose.

The -p 27017:27017 exposes the container publicly to be externally accessible on the host. Without that you can still connect to the container on the host through the container's IP address (found with docker inspect). But again although it's useful to include in the image's documentation it's not more relevant to this image than any other and the information is available on Docker's docs

[tianon]

Also, by default, MongoDB doesn't use authentication, so exposing port 27017 outside a Docker network or something similarly private is a pretty dangerous configuration. 🙈