fix race-condition on application.cfg when reloaded very fast

app/app.go

@@ -161,8 +161,7 @@ func (a *Application) Reload(cfg *config.Config) error {
 	if err := a.checkConfigCouldBeReloaded(cfg); err != nil {
 		return err
 	}
-	a.cfg = cfg
-	return a.reinitFromConfig()
+	return a.reinitFromConfig(cfg)
 }
 
 // Wait subscribes iteself to few signals and waits for any of them to be received.

app/init.go

@@ -20,8 +20,9 @@ import (
 	"github.com/ironsmile/nedomi/utils"
 )
 
-func (a *Application) reinitFromConfig() (err error) {
+func (a *Application) reinitFromConfig(cfg *config.Config) (err error) {
 	app := *a // copy
+	app.cfg = cfg
 
 	app.virtualHosts = make(map[string]*VirtualHost)
 	app.upstreams = make(map[string]types.Upstream)
@@ -70,6 +71,7 @@ func (a *Application) reinitFromConfig() (err error) {
 
 	a.Lock()
 	defer a.Unlock()
+	a.cfg = app.cfg
 	a.SetLogger(app.GetLogger())
 	a.virtualHosts = app.virtualHosts
 	a.upstreams = app.upstreams
@@ -92,7 +94,7 @@ func (a *Application) reinitFromConfig() (err error) {
 	return nil
 }
 
-// initFromConfig should be called when starting or reloading the app. It makes
+// initFromConfig should be called when starting but not when reloading the app. It makes
 // all the connections between cache zones, virtual hosts and upstreams.
 func (a *Application) initFromConfig() (err error) {
 	// Make the vhost and cacheZone maps
@@ -101,7 +103,7 @@ func (a *Application) initFromConfig() (err error) {
 	a.ctx, a.ctxCancel = context.WithCancel(context.Background())
 	a.ctx = contexts.NewAppContext(a.ctx, a)
 	a.ctx = contexts.NewCacheZonesContext(a.ctx, a.cacheZones)
-	return a.reinitFromConfig()
+	return a.reinitFromConfig(a.cfg)
 }
 
 func (a *Application) initCacheZone(cfgCz *config.CacheZone) (err error) {

app/init_test.go

@@ -92,8 +92,7 @@ func TestReinit(t *testing.T) {
 		Algorithm:      "lru",
 	}
 	replaceZone(&cfg, "zone2", cfg.CacheZones["zone3"])
-	app.cfg = &cfg
-	if err := app.reinitFromConfig(); err != nil {
+	if err := app.reinitFromConfig(&cfg); err != nil {
 		t.Fatalf("Error upon reiniting app: %s", err)
 	}