Add automatic book deployment

deploy/deploy-eacompanion

@@ -0,0 +1,44 @@
+#!/bin/bash
+set -euo pipefail
+
+repository_url="https://codeberg.org/simoncarrignon/EACompanion.git"
+repository_dir="/srv/EACompanion"
+web_root="/var/www/html/randomdrift"
+releases_dir="${web_root}/.EACompanion-releases"
+public_link="${web_root}/EACompanion"
+
+exec 9>/run/lock/eacompanion-deploy.lock
+flock -n 9 || exit 0
+
+if [[ ! -d "${repository_dir}/.git" ]]; then
+  git clone --branch main --single-branch "${repository_url}" "${repository_dir}"
+fi
+
+git -C "${repository_dir}" fetch --prune origin main
+revision="$(git -C "${repository_dir}" rev-parse FETCH_HEAD)"
+release_dir="${releases_dir}/${revision}"
+
+if [[ -f "${release_dir}/index.html" ]] && [[ "$(readlink -f "${public_link}" 2>/dev/null || true)" == "${release_dir}" ]]; then
+  chmod 0755 "${release_dir}"
+  exit 0
+fi
+
+git -C "${repository_dir}" checkout --detach --force "${revision}"
+mkdir -p "${releases_dir}"
+
+if [[ ! -f "${release_dir}/index.html" ]]; then
+  staging_dir="$(mktemp -d "${releases_dir}/.${revision}.XXXXXX")"
+  trap 'rm -rf -- "${staging_dir}"' EXIT
+
+  cd "${repository_dir}"
+  EA_OUTPUT_DIR="${staging_dir}" Rscript -e \
+    'bookdown::render_book("index.Rmd", output_format = "bookdown::gitbook", output_dir = Sys.getenv("EA_OUTPUT_DIR"), clean = TRUE)'
+  test -f "${staging_dir}/index.html"
+  mv "${staging_dir}" "${release_dir}"
+  trap - EXIT
+fi
+
+chmod 0755 "${release_dir}"
+temporary_link="${public_link}.new"
+ln -sfn "${release_dir}" "${temporary_link}"
+mv -Tf "${temporary_link}" "${public_link}"

deploy/eacompanion-deploy.service

@@ -0,0 +1,9 @@
+[Unit]
+Description=Render and deploy the EA Companion book
+Wants=network-online.target
+After=network-online.target
+
+[Service]
+Type=oneshot
+Environment=HOME=/root
+ExecStart=/usr/local/sbin/deploy-eacompanion

deploy/eacompanion-deploy.timer

@@ -0,0 +1,12 @@
+[Unit]
+Description=Check the EA Companion main branch for updates
+
+[Timer]
+OnBootSec=1min
+OnUnitActiveSec=2min
+RandomizedDelaySec=20s
+Persistent=true
+Unit=eacompanion-deploy.service
+
+[Install]
+WantedBy=timers.target