Deploying Static Sites With Docker and SSL
Sep 14, 2017
6 minute read


SSL is increasingly important in today’s web development workflow. No site, however small, is immune to the pitfalls of ignoring such knowledge - not even personal blogs like this one. When Google announced that its Chrome web browser would begin flagging non-SSL sites as “unsafe”; I knew it would be only be a matter of time before I would need to implement an SSL solution for this blog.

I put it off for a long time but a couple factors (including my blog breaking due to a Hugo upgrade) ultimately led me to redo the infrastructure of terriblecode.

NOTE: This blog post does not cover how to setup a server or a domain name with a DNS. For a tutorial on that I highly recommend DigitalOcean’s documentation

The New Criteria

So with the decision to redo the infrastructure, I had to lay a couple of ground rules:

  1. It had to have SSL which would be easy to setup
  2. It had to use Docker
  3. It had to work via git pushes

Getting SSL, the easy way

With the advent of letsencrypt, obtaining a browser trusted certificate is as simple as running a script.

And thus arrives: Caddy

Caddy Server

Using simple, direct syntax, Caddy has made getting SSL certificates as easy as entering an email address.

The blog post you’re currently reading is being statically served via Caddy, using a simple (literally, four lines long) configuration file to autonomously grab the SSL certificate. I could never have dreamed of such a possibility after using other web servers for so long.

Would you believe that this is the whole configuration file? {
    root /public

Dockerizing My Infrastructure

Moby Dock

I’ve been using Hugo as my static site generator for over a year. On the whole, I’ve found it to be quite good, but it isn’t perfect. I’ve never liked the idea of having to install a local binary. This was the issue which ultimately led to me breaking my blog a few weeks ago. I have always felt like there had to be a better way to do it.

I found a few Hugo images on Docker Hub already, but they were too big in size for my tastes and I thought I could slim down the Docker image. I utilized multi-stage Docker builds to build an image which was 25x smaller than the most popular Hugo image available on Docker Hub!

For implementation on this portion please take a look at the Github repository for hugo-docker.

For those asking, I also tried this with Caddy but could not achieve the same result due to ca-certificates needing to be installed for SSL to function correctly. I eventually settled on abiosoft/caddy as my Caddy image.

Deploying with Docker

Generating the site

So for static sites it’s fairly simple to generate a site, using my image you can generate a site like so (from a Makefile in the root directory of your site):


	docker run --rm -v "$(CURDIR)":/v -w /v seemethere/hugo-docker

NOTE: You may need a primer on docker run if you are not familiar with this syntax.

I generate the public directory using the Docker image I showed before, and then utilize rsync to update any changed files to a /public directory at the root of the file system.


	$(MAKE) -C /build public

/public: /build/public
	mkdir -p /public
	rsync -a -v /build/public

Serving the site

Serving the site is fairly simple once you generate the static pages.

For this I have a couple of Makefile targets:


.PHONY: run-caddy
	docker run \
		--name "$(CADDY_NAME)" \
		--restart always \
		-v /infra/Caddyfile:/etc/Caddyfile \
		-v /root/.caddy:/root/.caddy \
		-v /public:/public \
		-p 80:80 \
		-p 443:443 \
		-d \

.PHONY: relaunch-caddy
	docker kill $(CADDY_NAME)
	docker rm $(CADDY_NAME)
	$(MAKE) -C /infra run-caddy

The basic idea behind these targets is to:

  • Start a container with a name --name "$(CADDY_NAME)"
  • Volume mount my specific directories:
    • For my Caddyfile -v /infra/Caddyfile:/etc/Caddyfile
    • For storing certs -v /root/.caddy:/root/.caddy
    • For my static site -v /public:/public
  • Expose ports necessary to serve the site (80 and 443)
  • Let the container run in the background -d

I also have a Makefile target to re-launch the container but the only changes needed to update the site itself can be done by updating the files in /public.

Using Git Hooks to Deploy Changes

So far we’ve talked about how to get certificates and how to build and deploy infrastructure using Docker, but what about pushing up changes?

What if deploying your static site could be as simple as:

git push live

Getting to git push live

NOTE: A primer on Git hooks may be needed

So all of the magic of being able to do a git push live is located in a file called post-recieve. Basically, what git does is run post-recieve as a shell command after receiving files through a git push.

For our scenario we’ll assume that after a push we want three things to happen:

  1. Rebuild our static site
  2. Deploy our static site to the /public directory (if the rebuild passes)
  3. Launch a container that serves /public to the outside world with SSL
    • noop if the container is already running

The post-receive script for looks like:


#!/usr/bin/env bash

set -e


# Generate hugo docker image, clean out old versions
make -C /infra clean-hugo-image hugo-image

# Build static site in public directory, clean out old build directory
make -C /infra clean /public

# Run the container if it's not already running
# container restarts should be handled manually
if ! docker ps -a | grep "$CADDY_CONTAINER_NAME" >/dev/null; then
	make -C /infra run-caddy

Some of the Makefile targets might look familiar from the past sections! I’ve found it best to use Makefiles to help break problems into bite sized chunks so that even if one fails it’s usually fairly simple to debug and re-try locally.

Closing thoughts

All-in-all, the transition took about two nights worth of hair pulling to complete. This included building-out the infrastructure to the actual deployment of the website with the certificates.

Coming out of the transition I had a few thoughts:

  • Docker makes it easy to deploy this type of site on any Linux distribution that is supported by Docker
  • Caddy makes it extremely easy to get certificates and serve static sites
  • I wish more people knew how Makefiles worked so mine wouldn’t look so much like magic

Tweet me @_seemethere if you have any questions regarding this blog post, if you really liked the blog post, or if you find yourself in need of some assistance setting up a blog of your own!

Editing help provided by @petezhut and @mdmedey

If you are interested in the full code for setting up this infrastructure check out the Github repositories at:

Deploying Static Sites With Docker and SSL from programming