Jekyll in a Docker Container

But this has been done. Why not docker run jekyll/jekyll?

• I wanted two images, one for easy CLI (bretfisher/jekyll) and one for easy local server for dev with sane defaults (bretfisher/jekyll-serve), which I use 90% of the time
• So you can start any Jekyll server with docker-compose up
• I wanted to dev on a local Jekyll site without having Jekyll installed on my host OS
• I wanted it to be as easy as possible to start
• I wanted current amd64 and arm64 images using official Ruby and Jekyll latest

So, this does that.

Note I have courses on Docker (including a Lecture on Jekyll in Docker).

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⚠️ WARNING: ⚠️ This isn't meant to be a production image that you run a web server with. I don't do that with the Jekyll CLI that comes with this image. Jekyll CLI generates a static site that you can run with GitHub Pages, Netlify, or your own NGINX setup. Furthermore, I don't version anything so these images will not run guaranteed versions of Ruby, Jekyll, etc. (which, if you're running a server, should pin all versions usually.)

Docker Images

Image	Purpose	Example
bretfisher/jekyll	Runs Jekyll by default with no options, good for general CLI commands	docker run -v $(pwd):/site bretfisher/jekyll new .
bretfisher/jekyll-serve	Runs Jekyll serve with sane defaults, good for local Jekyll site dev	docker run -p 4000:4000 -v $(pwd):/site bretfisher/jekyll-serve

Getting Started

Creating a site:

cd to empty directory
docker run -v $(pwd):/site bretfisher/jekyll new .

Start a local server with sane defaults listening on port 4000:

cd dir/of/your/jekyll/site
docker run -p 4000:4000 -v $(pwd):/site bretfisher/jekyll-serve

That's it!

Details: it will mount your current path into the containers /site, bundle install before running jekyll serve to , serve it at http://<docker-host>:4000.

To make this even easier, copy docker-compose.yml from this repository to your jekyll site root. Then you'll only need to:

cd dir/of/your/jekyll/site
docker-compose up

Known issues

1. arm/v7 version (aka armhf) doesn't exist in this repository.
   • Yes, arm/v7 has become too difficult to support.
2. alpine version doesn't exist in this repository.
   • Yes, not all Jekyll dependencies are built with musl support, so glibc-based images are now the only option (Debian, Ubuntu, etc).
3. RESOLVED as of Jekyll 4.3 webrick errors during startup.
   • As of April 2021, Ruby 3.0 is out, and Jekyll is still on 4.2 (released 12/2020). Jekyll 4.2 doesn't have webrick listed as a dependency, so we'll have to manually add it to Gemfile for now if you want to use Ruby 3.0. Ruby 3.0 removed this bundled gems so you'll need to add them manually if you use them: sdbm, webrick, net-telnet, xmlrpc. Hopefully Jekyll 4.3 will have webrick listed as a Jekyll dependency (it is fixed in Jekyll master branch) so manually updating Gemfiles won't be needed.

Q&A

Q. What if I want to run other jekyll commands?

just add the jekyll options to the end of the bretfisher/jekyll:

docker run -v $(pwd):/site bretfisher/jekyll doctor

Q. What if I want to build a site with Gemfile dependencies?

As your Jekyll site gets fancier, you'll need to add Jekyll plugins via Ruby's Gemfile and bundle CLI. You'll need to do a bundle install first before building your Jekyll site.

If you were using this repo's image, you could:

docker run -v $(pwd):/site -it --entrypoint bash bretfisher/jekyll

Then run your commands interactively:

bundle install --retry 5 --jobs 20
bundle exec jekyll build

Then your bind-mounted _site will be there on your host, built by Jekyll using your Gemfile Jekyll dependencies that were installed in that container.

If this is something you do often, you'll want to build your own image that already has your Ruby dependencies installed. Then when you run the jekyll build command, it'll have all the Gemfile dependencies it needs.

License

MIT License

Copyright (c) [Bret Fisher bret@bretfisher.com]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.