Let a server service carry helper scripts and timers, starting with UseSend's cert refresh

bin/panama-server

@@ -4,8 +4,10 @@
 #
 # The repository carries the catalog: server/vps/<Name>/ holds a
 # compose.yml, a podman-<name>.service user unit, and an .env.example naming
-# what the service needs told. The machine carries the rest: ~/Server/<Name>/
-# is a real directory owning the .env (secrets never sit inside the checkout,
+# what the service needs told. A service may also carry helper units (any
+# other *.service or *.timer, e.g. a cert refresh) and helper files (scripts,
+# a README) beside them. The machine carries the rest: ~/Server/<Name>/ is a
+# real directory owning the .env (secrets never sit inside the checkout,
 # gitignored or not) and the bind-mounted data. Only the tracked files are
 # symlinked, so a `git clean` in the repo can never reach a database.
 #
@@ -83,12 +85,12 @@ require_service() {
   fi
 }
 
-# The one unit file a service directory carries. Its filename is its identity
-# -- podman-<name>.service, exactly what lands in the systemd user directory --
-# so nothing here invents a name that could drift from the file's.
+# The one compose unit a service directory carries. Its filename is its
+# identity -- podman-<name>.service, exactly what lands in the systemd user
+# directory -- so nothing here invents a name that could drift from the file's.
 unit_path_for() {
   local name="$1" unit
-  for unit in "$SERVER_DIR/$name"/*.service; do
+  for unit in "$SERVER_DIR/$name"/podman-*.service; do
     [[ -e "$unit" ]] || continue
     printf '%s' "$unit"
     return 0
@@ -96,6 +98,44 @@ unit_path_for() {
   return 1
 }
 
+# Every other unit in the directory: helper services and the timers that fire
+# them. They are linked beside the compose unit, and each timer is enabled.
+helper_units_for() {
+  local name="$1" unit
+  for unit in "$SERVER_DIR/$name"/*.service "$SERVER_DIR/$name"/*.timer; do
+    [[ -e "$unit" ]] || continue
+    [[ "$(basename "$unit")" == podman-*.service ]] && continue
+    printf '%s\n' "$unit"
+  done
+}
+
+# The files linked into ~/Server/<Name>/: every visible top-level file that is
+# not a unit. That is compose.yml plus any helper script or README; dotfiles
+# are skipped so .env.example (and a stray .env) never become links.
+live_files_for() {
+  local name="$1" file
+  for file in "$SERVER_DIR/$name"/*; do
+    [[ -f "$file" ]] || continue
+    case "$file" in *.service|*.timer) continue ;; esac
+    printf '%s\n' "$file"
+  done
+}
+
+link_service_files() {
+  local name="$1" file unit
+  mkdir -p "$TARGET_DIR/$name" "$UNIT_DIR"
+  while IFS= read -r file; do
+    link_file "$file" "$TARGET_DIR/$name/$(basename "$file")"
+  done < <(live_files_for "$name")
+  while IFS= read -r unit; do
+    link_file "$unit" "$UNIT_DIR/$(basename "$unit")"
+  done < <(helper_units_for "$name")
+}
+
+helper_timers_for() {
+  helper_units_for "$1" | grep '\.timer$' | xargs -r -n1 basename
+}
+
 unit_name_for() {
   local unit
   unit="$(unit_path_for "$1")" || return 1
@@ -111,10 +151,12 @@ unit_installed() {
   [[ -L "$UNIT_DIR/$unit_name" ]]
 }
 
+# Everything this machine links for the service, so a change to a helper
+# script or timer is reported by relink just like a compose change.
 definition_hash() {
-  local name="$1" unit
-  unit="$(unit_path_for "$name")" || unit=/dev/null
-  cat "$SERVER_DIR/$name/compose.yml" "$unit" 2>/dev/null | sha256sum | cut -d' ' -f1
+  local name="$1"
+  { live_files_for "$name"; unit_path_for "$name" && echo; helper_units_for "$name"; } \
+    | sort | xargs -r -d '\n' cat 2>/dev/null | sha256sum | cut -d' ' -f1
 }
 
 recorded_hash() {
@@ -198,6 +240,7 @@ cmd_enable() {
   fi
 
   mkdir -p "$UNIT_DIR"
+  link_service_files "$name"
   link_file "$unit_path" "$UNIT_DIR/$unit_name"
   systemctl --user daemon-reload
   if systemctl --user enable --now "$unit_name"; then
@@ -207,6 +250,10 @@ cmd_enable() {
     err "$unit_name did not start; see: systemctl --user status $unit_name"
     exit 1
   fi
+  local timer
+  for timer in $(helper_timers_for "$name"); do
+    systemctl --user enable --now "$timer" && ok "Enabled $timer"
+  done
 }
 
 cmd_disable() {
@@ -216,11 +263,15 @@ cmd_disable() {
   local unit_name
   unit_name="$(unit_name_for "$name")" || { err "$name has no unit file in the catalog"; exit 1; }
 
+  local timer unit
+  for timer in $(helper_timers_for "$name"); do
+    systemctl --user disable --now "$timer" 2>/dev/null || true
+  done
   systemctl --user disable --now "$unit_name" 2>/dev/null || true
-  if [[ -L "$UNIT_DIR/$unit_name" ]]; then
-    rm "$UNIT_DIR/$unit_name"
-    systemctl --user daemon-reload
-  fi
+  for unit in "$UNIT_DIR/$unit_name" $(helper_units_for "$name" | xargs -r -n1 basename | sed "s|^|$UNIT_DIR/|"); do
+    [[ -L "$unit" ]] && rm "$unit"
+  done
+  systemctl --user daemon-reload
   ok "$name disabled. ~/Server/$name, its .env and its data were not touched."
 }
 
@@ -267,8 +318,7 @@ cmd_relink() {
     unit_installed "$name" || continue
 
     link_file "$unit_path" "$UNIT_DIR/$unit_name"
-    mkdir -p "$TARGET_DIR/$name"
-    link_file "$SERVER_DIR/$name/compose.yml" "$TARGET_DIR/$name/compose.yml"
+    link_service_files "$name"
     refreshed=$((refreshed + 1))
 
     # Changed since the last time this machine looked, which is what makes a