core: start and restart a .deb's services after binary mode installs it

.github/workflows/verify-split-files.yml

@@ -71,6 +71,7 @@ on:
       - "tests/forge-clean-install.sh"
       - "tests/db-helper-context.sh"
       - "tests/forge-tag-spelling.sh"
+      - "tests/forge-deb-services.sh"
       - "tests/cs-clear.sh"
       - "tests/forge-appversion-scope.sh"
       - "tests/forge-singlefile-compressed.sh"
@@ -141,6 +142,7 @@ on:
       - "tests/forge-clean-install.sh"
       - "tests/db-helper-context.sh"
       - "tests/forge-tag-spelling.sh"
+      - "tests/forge-deb-services.sh"
       - "tests/cs-clear.sh"
       - "tests/forge-appversion-scope.sh"
       - "tests/forge-singlefile-compressed.sh"
@@ -301,6 +303,8 @@ jobs:
         run: bash tests/db-helper-context.sh
       - name: Pinned tag with or without its v tests
         run: bash tests/forge-tag-spelling.sh
+      - name: Services after a .deb install tests
+        run: bash tests/forge-deb-services.sh
       - name: Screen clear without a terminal tests
         run: bash tests/cs-clear.sh
       - name: App version pin and .deb stamp tests

lib/API.txt

@@ -17,6 +17,7 @@ _docker_setup_lxcfs_visibility
 _download_source_tarball
 _forge_asset_urls
 _forge_curl
+_forge_deb_units
 _forge_descriptor
 _forge_designated_release
 _forge_disk_full

lib/forge.func

@@ -2267,6 +2267,13 @@ _forge_is_script_app() {
   [[ "$fetched" == *"$script"* || "$script" == *"$fetched"* ]]
 }
 
+# Service units a package ships, templates (foo@) left out; none without systemd.
+_forge_deb_units() {
+  command -v systemctl >/dev/null 2>&1 || return 0
+  [[ -d /run/systemd/system ]] || return 0
+  dpkg -L "$1" 2>/dev/null | grep -E '/systemd/system/[^/@]+\.service$' | sed 's#.*/##' | sort -u
+}
+
 # ------------------------------------------------------------------------------
 # fetch_and_deploy_release()
 #
@@ -2460,13 +2467,35 @@ fetch_and_deploy_release() {
     local dpkg_opts=""
     [[ "${DPKG_FORCE_CONFOLD:-}" == "1" ]] && dpkg_opts="-o Dpkg::Options::=--force-confold"
     [[ "${DPKG_FORCE_CONFNEW:-}" == "1" ]] && dpkg_opts="-o Dpkg::Options::=--force-confnew"
+    # SYSTEMD_OFFLINE skips the package's own service start: restart what ran, start what a fresh install enabled.
+    local deb_pkg deb_fresh="" unit
+    local -a deb_was_active=()
+    deb_pkg="$(dpkg-deb -f "$tmpdir/$filename" Package 2>/dev/null)"
+    if [[ -n "$deb_pkg" ]]; then
+      if dpkg -s "$deb_pkg" >/dev/null 2>&1; then
+        for unit in $(_forge_deb_units "$deb_pkg"); do
+          systemctl is-active --quiet "$unit" 2>/dev/null && deb_was_active+=("$unit")
+        done
+      else
+        deb_fresh=1
+      fi
+    fi
     DEBIAN_FRONTEND=noninteractive SYSTEMD_OFFLINE=1 $STD apt install -y $dpkg_opts "$tmpdir/$filename" || {
       SYSTEMD_OFFLINE=1 dpkg -i "$tmpdir/$filename" >"$tmpdir/dpkg.log" 2>&1 || {
         _diagnose_deb_failure "$tmpdir/$filename" "$tmpdir/dpkg.log"
         _cs_repair_dpkg
         return 100
       }
     }
+    if [[ -n "$deb_pkg" ]]; then
+      for unit in $(_forge_deb_units "$deb_pkg"); do
+        if [[ " ${deb_was_active[*]} " == *" $unit "* ]]; then
+          systemctl restart "$unit" 2>/dev/null || msg_warn "${unit} did not restart after the ${deb_pkg} update"
+        elif [[ -n "$deb_fresh" ]] && systemctl is-enabled --quiet "$unit" 2>/dev/null; then
+          systemctl start "$unit" 2>/dev/null || msg_warn "${unit} did not start after installing ${deb_pkg}"
+        fi
+      done
+    fi
     ;;
 
   prebuild | singlefile)

tests/forge-deb-services.sh

@@ -0,0 +1,78 @@
+#!/usr/bin/env bash
+set -uo pipefail
+
+CORE_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)"
+eval "$(awk '/^(fetch_and_deploy_release|_forge_deb_units|_forge_workdir|_forge_is_script_app|_forge_descriptor|_forge_strip_v|_forge_previous_version)[(][)] [{]/,/^}/' "$CORE_DIR/lib/forge.func")"
+
+if [[ ! -d /run/systemd/system ]]; then
+  echo "SKIP: no /run/systemd/system on this machine"
+  exit 0
+fi
+
+TEST_DIR="$(mktemp -d)"
+trap 'rm -rf -- "$TEST_DIR"' EXIT
+export HOME="$TEST_DIR/home"
+mkdir -p "$HOME"
+LOG="$TEST_DIR/log"
+passed=0 failed=0
+
+check() {
+  if [[ "$3" == "$2" ]]; then
+    echo "PASS $1"
+    passed=$((passed + 1))
+  else
+    echo "FAIL $1: expected <$2>, got <$3>" >&2
+    sed 's/^/    /' "$LOG" >&2
+    failed=$((failed + 1))
+  fi
+}
+
+# shellcheck disable=SC2034  # read by the eval'd helpers
+STD=""
+jq() { command jq "$@" | tr -d '\r'; }
+msg_info() { :; }
+msg_ok() { :; }
+msg_warn() { echo "warn: $*" >>"$LOG"; }
+msg_error() { echo "error: $*" >>"$LOG"; }
+_forge_release_json() { printf '{"tag_name":"v2.0.0"}' >"$5"; }
+_forge_asset_urls() { echo "https://example.invalid/demo_2.0.0_amd64.deb"; }
+curl_download() { : >"$1"; }
+apt() { echo "apt $*" >>"$LOG"; }
+dpkg-deb() { echo demo; }
+dpkg() {
+  case "$1" in
+  --print-architecture) echo amd64 ;;
+  -s) [[ "$INSTALLED" == yes ]] ;;
+  -L) printf '%s\n' /usr/bin/demo /lib/systemd/system/demo.service \
+    /lib/systemd/system/demo-worker.service /lib/systemd/system/demo-job@.service ;;
+  esac
+}
+systemctl() {
+  case "$1" in
+  is-active) [[ " $ACTIVE " == *" $3 "* ]] ;;
+  is-enabled) [[ " $ENABLED " == *" $3 "* ]] ;;
+  restart | start) echo "$1 $2" >>"$LOG" ;;
+  esac
+}
+
+deploy() {
+  : >"$LOG"
+  rm -f "$HOME"/.demo*
+  fetch_and_deploy_release github demo owner/demo binary latest "" "demo_*_amd64.deb" >/dev/null 2>&1
+  grep -E '^(start|restart) ' "$LOG" | sort | tr '\n' ' ' | sed 's/ $//'
+}
+
+INSTALLED=no ACTIVE="" ENABLED="demo.service"
+check "fresh install starts the enabled unit only" "start demo.service" "$(deploy)"
+
+INSTALLED=yes ACTIVE="demo.service demo-worker.service" ENABLED="demo.service demo-worker.service"
+check "upgrade restarts the units that ran" "restart demo-worker.service restart demo.service" "$(deploy)"
+
+INSTALLED=yes ACTIVE="" ENABLED="demo.service"
+check "a unit stopped before the update stays stopped" "" "$(deploy)"
+
+INSTALLED=yes ACTIVE="demo.service" ENABLED="demo.service"
+check "templates are never touched" "0" "$(deploy >/dev/null; grep -c 'demo-job@' "$LOG")"
+
+echo "${passed} passed, ${failed} failed"
+[[ "$failed" -eq 0 ]]