add the config and compose modules

config: dotenv files are parsed, never sourced, so a value can hold a # or a $(...) without breaking or executing. The make engine included .env with make syntax, which neither allowed. compose: one call per project instead of one per sub-stack.
2026-09-03 18:29:36 +02:00
parent e7eab505e9
commit 990b99f0c0
4 changed files with 226 additions and 0 deletions
@@ -0,0 +1,79 @@
+#shellcheck shell=sh
+# config: where settings come from, and in which order.
+#
+# Layers, last one wins:
+#   defaults < /etc/conf.d/myos, /etc/default/myos < ~/.config/myos/config
+#           < <workdir>/.env < <workdir>/.env.<env> < environment < CLI VAR=val
+# MYOS_CONF_PRIORITY=system restores the old make behaviour where the system
+# file won over the project .env.
+#
+# Files are dotenv: KEY=value, one per line, # comments, optional quotes.
+# They are parsed, never sourced: a value never runs as code.
+
+# myos_dotenv_parse FILE  print normalized KEY=value lines
+myos_dotenv_parse() {
+  [ -f "$1" ] || return 0
+  sed -e 's/\r$//' -e '/^[[:space:]]*#/d' -e '/^[[:space:]]*$/d' "$1" |
+  while IFS= read -r _line; do
+    case $_line in *=*) ;; *) continue ;; esac
+    _k=${_line%%=*}
+    _v=${_line#*=}
+    _k=$(printf '%s' "$_k" | tr -d '[:space:]')
+    # whitespace around the = is not part of the value (make: s/[[:space:]]*=[[:space:]]*/=/)
+    _v=${_v#"${_v%%[![:space:]]*}"}
+    case $_k in ''|*[!A-Za-z0-9_]*) continue ;; esac
+    # strip one layer of matching quotes
+    case $_v in
+      \"*\") _v=${_v#\"}; _v=${_v%\"} ;;
+      \'*\') _v=${_v#\'}; _v=${_v%\'} ;;
+    esac
+    printf '%s=%s\n' "$_k" "$_v"
+  done
+}
+
+# myos_dotenv_load FILE  set the variables of FILE that are not already set
+# (an already exported variable wins, as `?=` does in make)
+myos_dotenv_load() {
+  [ -f "$1" ] || return 0
+  while IFS= read -r _kv; do
+    _k=${_kv%%=*}
+    [ -n "$(myos_var "$_k")" ] && continue
+    eval "$_k=\${_kv#*=}"
+  done <<EOF
+$(myos_dotenv_parse "$1")
+EOF
+}
+
+# myos_dotenv_has FILE KEY
+myos_dotenv_has() { myos_dotenv_parse "$1" | grep -q "^$2="; }
+
+# myos_conf_files  the system config files, most significant first
+myos_conf_files() {
+  [ -n "${MYOS_CONF:-}" ] && { printf '%s\n' "$MYOS_CONF"; return 0; }
+  for _f in /etc/conf.d/myos /etc/default/myos; do
+    [ -r "$_f" ] && printf '%s\n' "$_f"
+  done
+  return 0
+}
+
+# myos_env_vars FILE...  the ${VAR} names referenced by the compose files
+# (make: env-vars). $$VAR is a compose escape, not a shell variable.
+myos_env_vars() {
+  [ $# -gt 0 ] || return 0
+  sed 's/\$\$//g' "$@" 2>/dev/null |
+    grep -oE '\$\{?[A-Z0-9_]+' |
+    tr -d '{}$' |
+    sort -u |
+    tr '\n' ' ' |
+    sed 's/ $//'
+}
+
+# myos_env_export VAR...  print VAR='value' for each variable that has a value,
+# ready to be passed to env(1)
+myos_env_export() {
+  for _v in "$@"; do
+    _val=$(myos_var "$_v")
+    [ -n "$_val" ] && printf "%s=%s\n" "$_v" "$_val"
+  done
+  return 0
+}