fix processing of the args option

app.go

@@ -41,20 +41,27 @@ func (a *App) Provision(ctx caddy.Context) error {
 	}
 
 	a.log = ctx.Logger(a)
+	repl := caddy.NewReplacer()
 	for _, cmd := range a.Commands {
 		if err := cmd.provision(ctx, a); err != nil {
 			return err
 		}
-		a.addCmd(cmd)
-	}
-	return nil
-}
 
-func (a *App) addCmd(c Cmd) {
-	runner := runnerFunc(c.run)
-	for at := range c.at {
-		a.commands[at] = append(a.commands[at], runner)
+		// replace global placeholders
+		argv := make([]string, len(cmd.Args))
+		for index, argument := range cmd.Args {
+			argv[index] = repl.ReplaceAll(argument, "")
+		}
+
+		runner := runnerFunc(func() error {
+			return cmd.run(argv)
+		})
+
+		for at := range cmd.at {
+			a.commands[at] = append(a.commands[at], runner)
+		}
 	}
+	return nil
 }
 
 // Validate implements caddy.Validator

command.go

@@ -17,8 +17,7 @@ type Cmd struct {
 	Command string `json:"command,omitempty"`
 
 	// The command args.
-	Args []string
-	Argv []string `json:"args,omitempty"`
+	Args []string `json:"args,omitempty"`
 
 	// The directory to run the command from.
 	// Defaults to current directory.

middleware.go

@@ -42,13 +42,13 @@ func (m Middleware) Validate() error { return m.Cmd.validate() }
 func (m Middleware) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error {
 	repl := r.Context().Value(caddy.ReplacerCtxKey).(*caddy.Replacer)
 
+	// replace per-request placeholders
 	argv := make([]string, len(m.Args))
 	for index, argument := range m.Args {
 		argv[index] = repl.ReplaceAll(argument, "")
 	}
-	m.Argv = argv
 
-	err := m.run()
+	err := m.run(argv)
 
 	if m.PassThru {
 		if err != nil {
@@ -77,6 +77,5 @@ func (m Middleware) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddy
 // Cleanup implements caddy.Cleanup
 // TODO: ensure all running processes are terminated.
 func (m *Middleware) Cleanup() error {
-	m.Argv = nil
 	return nil
 }

run.go

@@ -17,12 +17,12 @@ type runnerFunc func() error
 
 func (r runnerFunc) Run() error { return r() }
 
-func (c *Cmd) run() error {
-	cmdInfo := zap.Any("command", append([]string{c.Command}, c.Argv...))
+func (c *Cmd) run(args []string) error {
+	cmdInfo := zap.Any("command", append([]string{c.Command}, args...))
 	log := c.log.With(cmdInfo)
 	startTime := time.Now()
 
-	cmd := exec.Command(c.Command, c.Argv...)
+	cmd := exec.Command(c.Command, args...)
 
 	done := make(chan struct{}, 1)
 
@@ -36,7 +36,7 @@ func (c *Cmd) run() error {
 			cancel()
 		}()
 
-		cmd = exec.CommandContext(ctx, c.Command, c.Argv...)
+		cmd = exec.CommandContext(ctx, c.Command, args...)
 	}
 
 	// configure command