This repo contains a base Docker image for use by Meteor apps built using a multistage Dockerfile. You might want to use this base because:
-
You can build/bundle your Meteor app as part of building your Docker image, rather than outside of Docker before the Docker build. This means the machine doing the building need not have Node or Meteor installed, which is important for continuous integration setups; and ensures repeatable builds, since the build environment is isolated and controlled.
-
Using a multistage
Dockerfile
on your app’s side means that you can publish a much smaller final Docker image that doesn’t have Meteor included, and you can also use an Alpine Linux base which is good for passing security scans (as it presents much less surface area in which scanners might find vulnerabilities).
Copy example/default.dockerfile
(or example/app-with-native-dependencies.dockerfile
if your app has native dependencies that require compilation such as bcrypt
, or if your app is using a version of Meteor older than 1.8.1) into the root of your project and rename it Dockerfile
. This file assumes that your Meteor app is one level down from the root in a folder named app
; either move your app there, or edit Dockerfile
to point to your desired path (or the root of your project). Leave Dockerfile
at the root.
Edit the Dockerfile
you copied into your project, changing the first line so that the numbers at the end match the version of Meteor of your project. For example:
FROM containerregistry.disney.com/wdi-shared/meteor-base:1.8.1
if your project is running under Meteor 1.8.1. See your app’s .meteor/release
file to get its Meteor release version. This version must match an available tag from disney/meteor-base.
Also copy in example/.dockerignore
and example/docker-compose.yml
to your project’s root. Then, from the root of your project:
docker-compose up
This builds an image for your app and starts it, along with a linked container for MongoDB. Go to http://localhost/ to see your app running.
Feel free to edit the Dockerfile
you copied into your project, for example to add Linux dependencies. The beauty of the multistage build pattern is that this base image can stay lean, without needing ONBUILD
triggers or configuration files for you to influence the image that gets built. You control the final image via your own Dockerfile
, so you can do whatever you want.
There are several great Meteor Docker images out there. We built this one because none of the existing open source ones met our needs:
-
jshimko/meteor-launchpad is great, but it’s based on
debian:jessie
, which fails the security scan we run on all of our Docker images. Debian is also larger than Alpine. This project also always downloads and installs Meteor on every production build, rather than caching it as this base image does. -
meteor/galaxy-images and Treecom/meteor-alpine both require building the Meteor app in the host machine, before copying the built app into the Docker container. We wanted to avoid needing Node and Meteor installed on our CI servers, and we want the predictability of building within the Docker environment.
Other projects I looked at generally had one or more of the disadvantages cited above. Multistage Docker builds have only been possible since Docker 17.05, which came out in May 2017, and most projects on the Web were designed before then and therefore don’t take advantage of the possibilities offered by a multistage architecture.