Docker-based build process (#34)

moves to a docker-based, reproducible build environment

Author: jacoscaz

.github/workflows/deploy.yml

@@ -14,15 +14,8 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
-      - name: Install requirements
-        run: |
-            pip install -r requirements.txt
-            wget https://github.com/gohugoio/hugo/releases/download/v0.128.2/hugo_extended_0.128.2_linux-amd64.deb -O /tmp/hugo.deb
-            sudo dpkg -i /tmp/hugo.deb
       - name: Build Website
-        run: |
-            ./grabrepos.py
-            hugo
+        run: ./build.sh
       - if: github.event_name == 'push' || github.event_name == 'workflow_dispatch' || github.event_name == 'repository_dispatch' && always()
         name: Deploy website
         uses: peaceiris/actions-gh-pages@v4

README.md

@@ -4,34 +4,24 @@ This repository contains the website sources for the [Homie Website](https://hom
 including the online validator javascript tool.
 
 The build is triggered by a change in any of the Homie specification respositories
-and performed by Travis CI. The resulting webpage is uploaded to 
+and performed by GitHub Actions. The resulting webpage is uploaded to
 https://github.com/homieiot/homieiot.github.io/tree/master and is served by GitHub.
 
 The generator in use is [Hugo](https://gohugo.io/).
 
-You can just call the `./build.sh` script within this directory
-and find the page in the output directory `site`.
+## How to build locally
 
-## Manually generate the webpage
+Just call the `./build.sh` script within this repository. The built website
+will be available in the `./public` directory.
 
-You need Hugo in the extended version (with sass/scss support).
+The only dependency required by the `./build.sh` script is [Docker],
+which is used to create a builder image with the actual dependencies
+required to build the website (Git, Hugo, Python and the dependencies
+for the `./grabrepos.py` script).
 
-The git grab utility requires python3. For a non-root environment,
-it is recommended to create a python virtual environment:
+The builder image is then used to build the website.
 
-```sh
-python3 -m venv dependencies
-source dependencies/bin/activate
-```
-
-Install the dependencies `gitpython`, `pyyaml`,
-then run the git grab utility and and hugo last:
-
-```
-pip install -r requirements.txt
-./grabrepos.py
-hugo
-```
+[Docker]: https://www.docker.com
 
 ## Upload a manually generated webpage
 

build.sh

@@ -1,12 +1,10 @@
-#!/usr/bin/env bash
-set -euo pipefail
+#!/usr/bin/env sh
+set -euo
 
-echo "Manually building webpage"
+# As long as no changes are made to the Dockerfile, the built image
+# will be cached and reused in all builds after the first one.
+docker build -t homie-website-builder -f ./docker/Dockerfile-builder .
 
-python3 -m venv dependencies
-source dependencies/bin/activate
-pip install -r requirements.txt
-./grabrepos.py
-hugo
-
-echo "Webpage available at ./site"
+# No need for a dedicated entrypoint script, we can specify the commands
+# to run as arguments to `docker run`. This keeps our image more flexible.
+docker run --rm -v "$(pwd):/data" homie-website-builder sh -c "cd /data && ./grabrepos.py && hugo"

docker/Dockerfile-builder

@@ -0,0 +1,20 @@
+
+# This Dockerfile is not meant to be used directly but, rather,
+# through the ../build.sh script.
+
+# Build upon an official Python image using Alpine Linux as its base, which
+# tends to result in smaller images and faster builds. As we want our build
+# environment to be as reproducible as possible, we pin both the Python version
+# and the Alpine Linux version to ensure consistent builds.
+FROM python:3.12-alpine3.21
+
+# Update Alpine's package list.
+RUN apk update
+
+# Install OS-level dependencies (Git and Hugo). The versions of these packages
+# are implicitly pinned to the Alpine Linux version used in the FROM statement.
+RUN apk add --no-cache git hugo
+
+# Copy list of Python dependencies and install them.
+COPY ./requirements.txt /requirements.txt
+RUN pip install -r /requirements.txt