agent: Adding watches config

command/agent/config.go

@@ -229,6 +229,11 @@ type Config struct {
 	//                    this acts like deny.
 	ACLDownPolicy string `mapstructure:"acl_down_policy"`
 
+	// Watches are used to monitor various endpoints and to invoke a
+	// handler to act appropriately. These are managed entirely in the
+	// agent layer using the standard APIs.
+	Watches []string `mapstructure:"watches"`
+
 	// AEInterval controls the anti-entropy interval. This is how often
 	// the agent attempts to reconcile it's local state with the server'
 	// representation of our state. Defaults to every 60s.
@@ -648,6 +653,9 @@ func MergeConfig(a, b *Config) *Config {
 	if b.ACLDefaultPolicy != "" {
 		result.ACLDefaultPolicy = b.ACLDefaultPolicy
 	}
+	if len(b.Watches) != 0 {
+		result.Watches = append(result.Watches, b.Watches...)
+	}
 
 	// Copy the start join addresses
 	result.StartJoin = make([]string, 0, len(a.StartJoin)+len(b.StartJoin))

command/agent/config_test.go

@@ -384,6 +384,20 @@ func TestDecodeConfig(t *testing.T) {
 	if config.ACLDefaultPolicy != "deny" {
 		t.Fatalf("bad: %#v", config)
 	}
+
+	// Watches
+	input = `{"watches": ["type:keyprefix prefix:foo/ handler:foobar"]}`
+	config, err = DecodeConfig(bytes.NewReader([]byte(input)))
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if len(config.Watches) != 1 {
+		t.Fatalf("bad: %#v", config)
+	}
+	if config.Watches[0] != "type:keyprefix prefix:foo/ handler:foobar" {
+		t.Fatalf("bad: %#v", config)
+	}
 }
 
 func TestDecodeConfig_Service(t *testing.T) {
@@ -538,6 +552,7 @@ func TestMergeConfig(t *testing.T) {
 		ACLTTLRaw:              "15s",
 		ACLDownPolicy:          "deny",
 		ACLDefaultPolicy:       "deny",
+		Watches:                []string{"type:keyprefix prefix:foobar/ handler:foo"},
 	}
 
 	c := MergeConfig(a, b)