Merge pull request #333 from mholt/firststartup

startup: Only run commands at first startup

caddy/caddy.go

@@ -71,6 +71,10 @@ var (
 	// index in the list of inherited file descriptors. This
 	// variable is not safe for concurrent access.
 	loadedGob caddyfileGob
+
+	// startedBefore should be set to true if caddy has been
+	// started at least once.
+	startedBefore bool
 )
 
 const (
@@ -128,6 +132,7 @@ func Start(cdyfile Input) (err error) {
 	if err != nil {
 		return err
 	}
+	startedBefore = true
 
 	// Close remaining file descriptors we may have inherited that we don't need
 	if IsRestart() {
@@ -203,6 +208,18 @@ func startServers(groupings bindingGroup) error {
 		wg.Add(1)
 		go func(s *server.Server, ln server.ListenerFile) {
 			defer wg.Done()
+
+			// run startup functions that should only execute when
+			// the original parent process is starting.
+			if !IsRestart() && !startedBefore {
+				err := s.RunFirstStartupFuncs()
+				if err != nil {
+					errChan <- err
+					return
+				}
+			}
+
+			// start the server
 			if ln != nil {
 				errChan <- s.Serve(ln)
 			} else {

caddy/setup/startupshutdown.go

@@ -10,7 +10,7 @@ import (
 
 // Startup registers a startup callback to execute during server start.
 func Startup(c *Controller) (middleware.Middleware, error) {
-	return nil, registerCallback(c, &c.Startup)
+	return nil, registerCallback(c, &c.FirstStartup)
 }
 
 // Shutdown registers a shutdown callback to execute during process exit.

caddy/setup/startupshutdown_test.go

@@ -45,7 +45,7 @@ func TestStartup(t *testing.T) {
 		if err != nil {
 			t.Errorf("Expected no errors, got: %v", err)
 		}
-		err = c.Startup[0]()
+		err = c.FirstStartup[0]()
 		if err != nil && !test.shouldExecutionErr {
 			t.Errorf("Test %d recieved an error of:\n%v", i, err)
 		}

server/config.go

@@ -26,11 +26,21 @@ type Config struct {
 	// Middleware stack; map of path scope to middleware -- TODO: Support path scope?
 	Middleware map[string][]middleware.Middleware
 
-	// Functions (or methods) to execute at server start; these
+	// Startup is a list of functions (or methods) to execute at
-	// are executed before any parts of the server are configured,
+	// server startup and restart; these are executed before any
-	// and the functions are blocking
+	// parts of the server are configured, and the functions are
+	// blocking. These are good for setting up middlewares and
+	// starting goroutines.
 	Startup []func() error
 
+	// FirstStartup is like Startup but these functions only execute
+	// during the initial startup, not on subsequent restarts.
+	//
+	// (Note: The server does not ever run these on its own; it is up
+	// to the calling application to do so, and do so only once, as the
+	// server itself has no notion whether it's a restart or not.)
+	FirstStartup []func() error
+
 	// Functions (or methods) to execute when the server quits;
 	// these are executed in response to SIGINT and are blocking
 	Shutdown []func() error

server/server.go

@@ -371,6 +371,23 @@ func setupClientAuth(tlsConfigs []TLSConfig, config *tls.Config) error {
 	return nil
 }
 
+// RunFirstStartupFuncs runs all of the server's FirstStartup
+// callback functions unless one of them returns an error first.
+// It is up the caller's responsibility to call this only once and
+// at the correct time. The functions here should not be executed
+// at restarts or where the user does not explicitly start a new
+// instance of the server.
+func (s *Server) RunFirstStartupFuncs() error {
+	for _, vh := range s.vhosts {
+		for _, f := range vh.config.FirstStartup {
+			if err := f(); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
 // tcpKeepAliveListener sets TCP keep-alive timeouts on accepted
 // connections. It's used by ListenAndServe and ListenAndServeTLS so
 // dead TCP connections (e.g. closing laptop mid-download) eventually