release: build docs as container image

Signed-off-by: David Karlsson <35727626+dvdksn@users.noreply.github.com>

Author: dvdksn

.github/workflows/deploy.yml

@@ -155,3 +155,21 @@ jobs:
         if: ${{ env.SEND_SLACK_MSG == 'true' }}
         run: |
           curl -X POST -H 'Content-type: application/json' --data '{"text":"${{ env.DOCS_SLACK_MSG }}"}' ${{ secrets.SLACK_WEBHOOK }}
+  image:
+    runs-on: ubuntu-22.04
+    if: github.repository_owner == 'docker'
+    steps:
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      -
+        name: Build website
+        uses: docker/bake-action@v5
+        with:
+          files: |
+            docker-bake.hcl
+          targets: image
+          set: |
+            *.cache-from=type=gha,scope=deploy-${{ env.BRANCH_NAME }}
+            *.cache-to=type=gha,scope=deploy-${{ env.BRANCH_NAME }},mode=max
+          push: true

Dockerfile

@@ -6,6 +6,7 @@ ARG ALPINE_VERSION=3.20
 ARG GO_VERSION=1.22
 # HTML_TEST_VERSION sets the wjdp/htmltest version for HTML testing
 ARG HTMLTEST_VERSION=0.17.0
+ARG NGINX_VERSION=1.27
 
 # base is the base stage with build dependencies
 FROM golang:${GO_VERSION}-alpine AS base
@@ -41,7 +42,9 @@ FROM build-base AS build
 ARG HUGO_ENV
 # DOCS_URL sets the base URL for the site
 ARG DOCS_URL
-RUN hugo --gc --minify -d /out -e $HUGO_ENV -b $DOCS_URL
+ENV HUGO_ENVIRONMENT=$HUGO_ENV
+ENV HUGO_BASEURL=$DOCS_URL
+RUN hugo --gc --minify -d /out
 
 # lint lints markdown files
 FROM davidanson/markdownlint-cli2:v0.12.1 AS lint
@@ -129,6 +132,10 @@ set -ex
 ./scripts/test_go_redirects.sh
 EOT
 
+# image creates a Docker image for the documentation site
+FROM nginx:${NGINX_VERSION}-alpine AS image
+COPY --from=release / /usr/share/nginx/html
+
 # release is an empty scratch image with only compiled assets
 FROM scratch AS release
 COPY --from=build /out /

docker-bake.hcl

@@ -32,6 +32,20 @@ target "release" {
   output = [DOCS_SITE_DIR]
 }
 
+target "image" {
+  args = {
+    HUGO_ENV = HUGO_ENV
+    DOCS_URL = ""
+  }
+  target = "image"
+  attest = [
+    "type=provenance,mode=max",
+    "type=sbom",
+  ]
+  tags = ["docs/docker-docs:latest"]
+  output = ["type=docker"]
+}
+
 group "validate" {
   targets = ["lint", "test", "unused-media", "test-go-redirects"]
 }