Declare passive

declaration.go

@@ -8,7 +8,9 @@ type Declaration func(Declarer) error
 // Declarer is implemented by *amqp.Channel
 type Declarer interface {
 	QueueDeclare(name string, durable, autoDelete, exclusive, noWait bool, args amqp.Table) (amqp.Queue, error)
+	QueueDeclarePassive(name string, durable, autoDelete, exclusive, noWait bool, args amqp.Table) (amqp.Queue, error)
 	ExchangeDeclare(name, kind string, durable, autoDelete, internal, noWait bool, args amqp.Table) error
+	ExchangeDeclarePassive(name, kind string, durable, autoDelete, internal, noWait bool, args amqp.Table) error
 	QueueBind(name, key, exchange string, noWait bool, args amqp.Table) error
 }
 
@@ -31,6 +33,25 @@ func DeclareQueue(q *Queue) Declaration {
 	}
 }
 
+// DeclareQueuePassive is a way to declare AMQP queue
+func DeclareQueuePassive(q *Queue) Declaration {
+	name := q.Name
+	return func(c Declarer) error {
+		q.Name = name
+		realQ, err := c.QueueDeclarePassive(q.Name,
+			q.Durable,
+			q.AutoDelete,
+			q.Exclusive,
+			false,
+			q.Args,
+		)
+		q.l.Lock()
+		q.Name = realQ.Name
+		q.l.Unlock()
+		return err
+	}
+}
+
 // DeclareExchange is a way to declare AMQP exchange
 func DeclareExchange(e Exchange) Declaration {
 	return func(c Declarer) error {
@@ -45,6 +66,20 @@ func DeclareExchange(e Exchange) Declaration {
 	}
 }
 
+// DeclareExchange is a way to declare AMQP exchange
+func DeclareExchangePassive(e Exchange) Declaration {
+	return func(c Declarer) error {
+		return c.ExchangeDeclarePassive(e.Name,
+			e.Kind,
+			e.Durable,
+			e.AutoDelete,
+			false,
+			false,
+			e.Args,
+		)
+	}
+}
+
 // DeclareBinding is a way to declare AMQP binding between AMQP queue and exchange
 func DeclareBinding(b Binding) Declaration {
 	return func(c Declarer) error {

declaration_test.go

@@ -7,21 +7,33 @@ import (
 )
 
 type testDeclarer struct {
-	_QueueDeclare    func(string) (amqp.Queue, error)
-	_ExchangeDeclare func() error
-	_QueueBind       func() error
+	_QueueDeclare           func(string) (amqp.Queue, error)
+	_QueueDeclarePassive    func(string) (amqp.Queue, error)
+	_ExchangeDeclare        func() error
+	_ExchangeDeclarePassive func() error
+	_QueueBind              func() error
 }
 
 func (td *testDeclarer) QueueDeclare(name string, durable, autoDelete,
 	exclusive, noWait bool, args amqp.Table) (amqp.Queue, error) {
 	return td._QueueDeclare(name)
 }
 
+func (td *testDeclarer) QueueDeclarePassive(name string, durable, autoDelete,
+	exclusive, noWait bool, args amqp.Table) (amqp.Queue, error) {
+	return td._QueueDeclarePassive(name)
+}
+
 func (td *testDeclarer) ExchangeDeclare(name, kind string, durable, autoDelete,
 	internal, noWait bool, args amqp.Table) error {
 	return td._ExchangeDeclare()
 }
 
+func (td *testDeclarer) ExchangeDeclarePassive(name, kind string, durable, autoDelete,
+	internal, noWait bool, args amqp.Table) error {
+	return td._ExchangeDeclarePassive()
+}
+
 func (td *testDeclarer) QueueBind(name, key, exchange string, noWait bool,
 	args amqp.Table) error {
 	return td._QueueBind()
@@ -64,6 +76,43 @@ func TestDeclareQueue(t *testing.T) {
 	}
 }
 
+func TestDeclareQueuePassive(t *testing.T) {
+	var (
+		callOK, nameOK bool
+	)
+
+	q := &Queue{
+		Name: "Q1 Passive",
+	}
+
+	td := &testDeclarer{
+		_QueueDeclarePassive: func(name string) (amqp.Queue, error) {
+			callOK = true
+			if name == "Q1 Passive" {
+				nameOK = true
+			}
+			return amqp.Queue{Name: "Q1_REAL_PASSIVE"}, nil
+		},
+	}
+
+	testDec := DeclareQueuePassive(q)
+	testDec(td)
+
+	if !callOK {
+		t.Error("DeclareQueuePassive() should call declarer.QueueDeclarePassive()")
+	}
+
+	if q.Name != "Q1_REAL_PASSIVE" {
+		t.Error("DeclareQueuePassive() should update queue name from AMQP reply")
+	}
+
+	// call it another time (like reconnect event happened)
+	testDec(td)
+	if !nameOK {
+		t.Error("queue name should be preserved")
+	}
+}
+
 func TestDeclareExchange(t *testing.T) {
 	var ok bool
 
@@ -83,6 +132,25 @@ func TestDeclareExchange(t *testing.T) {
 	}
 }
 
+func TestDeclareExchangePassive(t *testing.T) {
+	var ok bool
+
+	e := Exchange{Name: "ex1passive"}
+
+	td := &testDeclarer{
+		_ExchangeDeclarePassive: func() error {
+			ok = true
+			return nil
+		},
+	}
+
+	DeclareExchangePassive(e)(td)
+
+	if !ok {
+		t.Error("DeclareExchangePassive() should call declarer.ExchangeDeclarePassive()")
+	}
+}
+
 func TestDeclareBinding(t *testing.T) {
 	var ok bool