This is a docker baseimage that can be used to create containers for any long-lived application.
Multiple docker images, based on different Linux distributions, are available:
Base Distribution | Docker Image Base Tag | Size |
---|---|---|
Alpine 3.16 | alpine-3.16 | |
Alpine 3.17 | alpine-3.17 | |
Alpine 3.18 | alpine-3.18 | |
Alpine 3.19 | alpine-3.19 | |
Alpine 3.20 | alpine-3.20 | |
Alpine 3.21 | alpine-3.21 | |
Debian 10 | debian-10 | |
Debian 11 | debian-11 | |
Ubuntu 16.04 LTS | ubuntu-16.04 | |
Ubuntu 18.04 LTS | ubuntu-18.04 | |
Ubuntu 20.04 LTS | ubuntu-20.04 | |
Ubuntu 22.04 LTS | ubuntu-22.04 |
Here are the main components of the baseimage:
- An init system.
- A process supervisor, with proper PID 1 functionality (proper reaping of processes).
- Useful tools to ease container building.
- Environment to better support dockerized applications.
Images are versioned. Version number follows the semantic versioning. The
version format is MAJOR.MINOR.PATCH
, where an increment of the:
MAJOR
version indicates that a backwards-incompatible change has been done.MINOR
version indicates that functionality has been added in a backwards-compatible manner.PATCH
version indicates that a bug fix has been done in a backwards-compatible manner.
The baseimage is available under multiple tags. A tag is made from the corresponding Linux distribution and the release version.
Tag | Description |
---|---|
distro-vX.Y.Z | Exact version of the image. |
distro-vX.Y | Latest version of a specific minor version of the image. |
distro-vX | Latest version of a specific major version of the image. |
The Dockerfile
for your application can be very simple, as only three things
are required:
- Instructions to install the application.
- A script that starts the application (stored at
/startapp.sh
in container). - The name of the application.
Here is an example of a docker file that would be used to run a simple web
NodeJS server.
In Dockerfile
:
# Pull base image.
FROM jlesage/baseimage:alpine-3.15-v3
# Install http-server.
RUN add-pkg nodejs-npm && \
npm install http-server -g
# Copy the start script.
COPY startapp.sh /startapp.sh
# Set the name of the application.
RUN set-cont-env APP_NAME "http-server"
# Expose ports.
EXPOSE 8080
In startapp.sh
:
#!/bin/sh
exec /usr/bin/http-server
Then, build your docker image:
docker build -t docker-http-server .
And run it:
docker run --rm -p 8080:8080 docker-http-server
You should be able to access the HTTP server by opening in a web browser:
http://[HOST IP ADDR]:8080
Full documentation is available at https://github.com/jlesage/docker-baseimage.