Whalepod

Quickly generate Dockerfiles

Maintaining multiple Docker images for various version of an application - for example, Node.js - can become tricky past a certain point. Whalepod aims to make it easier to generate and maintain Dockerfiles using templates and YAML, and creating the neccesary tooling configuration to build and push them.

Proof of concept using Whalepod: https://github.com/gmemstr/flutter-fastlane-android

whalepod.yml

The whalepod.yml file contains the information neccesary to generate the Docker images. It requires a few things; first a name for the Docker image, followed by a list of versions, optional parameters, and a template Dockerfile that will be processed.

Example whalepod.yml

name: whalepod-example
versions:
  - 1.0
  - 1.1
  - 1.2
  - 2.0
  - 3.0
parameters:
  hello_to: "Docker"
template: |
  FROM alpine:3.7
  LABEL version="<<version>>"

  RUN echo Hello <<params.hello_to>>!

Running

Running whalepod is as simple as executing the command with a valid whalepod.yml file. If your whalepod.yml file is located elsewhere or is named something other than whalepod.yml, you can specify another file with whalepod <filename>.

Each Dockerfile will live in it's own directory based on the version, and a Makefile will be generated alongside it with pre-filled commands to build the images. An alternative output folder can be specified by passing through the --output <directory> (-o=<directory>) flag.

TODO: add docker push command to Makefile

whalepod 0.1.0
Quickly generate Dockerfiles from YAML

USAGE:
    whalepod [OPTIONS] [path]

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
    -o, --output <output>     [default: .]

ARGS:
    <path>    The path to configuration file [default: whalepod.yml]

Disclaimer

This is very much an experiment, and my first foray into Rust. Feedback and contributions are welcome - I intend to maintain it moving forward, and I do not intend to introduce breaking changes, however keep that in mind!