move logic for testing equality for vault config

command/agent/command.go

@@ -740,28 +740,16 @@ func (c *Command) handleReload() {
 		}
 	}
 
-	var shouldReloadVault bool
-	switch {
-	case c.agent.config.Vault == nil && newConf.Vault != nil:
-		fallthrough
-	case c.agent.config.Vault != nil && newConf.Vault == nil:
-		fallthrough
-	case c.agent.config.Vault != nil && !c.agent.config.Vault.IsEqual(newConf.Vault):
-		shouldReloadVault = true
-	}
-
-	if shouldReloadRPC || shouldReloadVault {
-		if s := c.agent.Server(); s != nil {
-			sconf, err := convertServerConfig(newConf, c.logOutput)
-			c.agent.logger.Printf("[DEBUG] agent: starting reload of server config")
-			if err != nil {
-				c.agent.logger.Printf("[ERR] agent: failed to convert server config: %v", err)
+	if s := c.agent.Server(); s != nil {
+		sconf, err := convertServerConfig(newConf, c.logOutput)
+		c.agent.logger.Printf("[DEBUG] agent: starting reload of server config")
+		if err != nil {
+			c.agent.logger.Printf("[ERR] agent: failed to convert server config: %v", err)
+			return
+		} else {
+			if err := s.Reload(sconf); err != nil {
+				c.agent.logger.Printf("[ERR] agent: reloading server config failed: %v", err)
 				return
-			} else {
-				if err := s.Reload(sconf); err != nil {
-					c.agent.logger.Printf("[ERR] agent: reloading server config failed: %v", err)
-					return
-				}
 			}
 		}
 	}

nomad/vault.go

@@ -316,6 +316,11 @@ func (v *vaultClient) SetConfig(config *config.VaultConfig) error {
 	v.l.Lock()
 	defer v.l.Unlock()
 
+	// If reloading the same config, no-op
+	if v.config.IsEqual(config) {
+		return nil
+	}
+
 	// Kill any background routines
 	if v.running {
 		// Stop accepting any new request

nomad/vault_test.go

@@ -437,6 +437,31 @@ func TestVaultClient_SetConfig(t *testing.T) {
 	if client.tokenData == nil || len(client.tokenData.Policies) != 3 {
 		t.Fatalf("unexpected token: %v", client.tokenData)
 	}
+
+	// test that when SetConfig is called with the same configuration, it is a
+	// no-op
+	failCh := make(chan struct{}, 1)
+	go func() {
+		tomb := client.tomb
+		select {
+		case <-tomb.Dying():
+			close(failCh)
+		case <-time.After(1 * time.Second):
+			return
+		}
+	}()
+
+	// Update the config
+	if err := client.SetConfig(v2.Config); err != nil {
+		t.Fatalf("SetConfig failed: %v", err)
+	}
+
+	select {
+	case <-failCh:
+		t.Fatalf("Tomb shouldn't have exited")
+	case <-time.After(1 * time.Second):
+		return
+	}
 }
 
 // Test that we can disable vault