From 8a8aef05034fc5270e44221f48eb43eb8cde0aff Mon Sep 17 00:00:00 2001
From: Ryan Uber <ru@ryanuber.com>
Date: Mon, 24 Aug 2015 18:52:31 -0700
Subject: [PATCH] consul/state: add service delete functions

---
 consul/state/state_store.go      | 39 ++++++++++++++++++++++++++++
 consul/state/state_store_test.go | 44 +++++++++++++++++++++++++++++++-
 2 files changed, 82 insertions(+), 1 deletion(-)

diff --git a/consul/state/state_store.go b/consul/state/state_store.go
index 4d11a072e4..44c1f8472d 100644
--- a/consul/state/state_store.go
+++ b/consul/state/state_store.go
@@ -133,6 +133,8 @@ func (s *StateStore) DeleteNode(idx uint64, nodeID string) error {
 	return nil
 }
 
+// deleteNodeTxn is the inner method used for removing a node from
+// the store within a given transaction.
 func (s *StateStore) deleteNodeTxn(idx uint64, nodeID string, tx *memdb.Txn) error {
 	// Look up the node
 	node, err := tx.First("nodes", "id", nodeID)
@@ -263,3 +265,40 @@ func (s *StateStore) NodeServices(nodeID string) (*structs.NodeServices, error)
 
 	return ns, nil
 }
+
+// DeleteNodeService is used to delete a given service associated
+// with the given node.
+func (s *StateStore) DeleteNodeService(idx uint64, nodeID, serviceID string) error {
+	tx := s.db.Txn(true)
+	defer tx.Abort()
+
+	// Call the service deletion
+	if err := s.deleteNodeServiceTxn(idx, nodeID, serviceID, tx); err != nil {
+		return err
+	}
+
+	tx.Commit()
+	return nil
+}
+
+// deleteNodeServiceTxn is the inner method called to remove a service
+// registration within an existing transaction.
+func (s *StateStore) deleteNodeServiceTxn(idx uint64, nodeID, serviceID string, tx *memdb.Txn) error {
+	// Look up the service
+	service, err := tx.First("services", "id", nodeID, serviceID)
+	if err != nil {
+		return fmt.Errorf("failed service lookup: %s", err)
+	}
+
+	// Delete the service and update the index
+	if err := tx.Delete("services", service); err != nil {
+		return fmt.Errorf("failed deleting service: %s", err)
+	}
+	if err := tx.Insert("index", &IndexEntry{"services", idx}); err != nil {
+		return fmt.Errorf("failed updating index: %s", err)
+	}
+
+	// TODO: session invalidation
+	// TODO: watch trigger
+	return nil
+}
diff --git a/consul/state/state_store_test.go b/consul/state/state_store_test.go
index c60fc2d18b..678f2dc343 100644
--- a/consul/state/state_store_test.go
+++ b/consul/state/state_store_test.go
@@ -145,7 +145,7 @@ func TestStateStore_DeleteNode(t *testing.T) {
 
 	// The node is now gone
 	if n, err := s.GetNode("node1"); err != nil || n != nil {
-		t.Fatalf("bad: %#v (%#v)", node, err)
+		t.Fatalf("bad: %#v (err: %#v)", node, err)
 	}
 }
 
@@ -226,3 +226,45 @@ func TestStateStore_EnsureService_NodeServices(t *testing.T) {
 		t.Fatalf("bad index: %d, %d", out.CreateIndex, out.ModifyIndex)
 	}
 }
+
+func TestStateStore_DeleteNodeService(t *testing.T) {
+	s := testStateStore(t)
+
+	// Register a node
+	node := &structs.Node{
+		Node:    "node1",
+		Address: "1.1.1.1",
+	}
+	if err := s.EnsureNode(1, node); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// Create a service
+	service := &structs.NodeService{
+		ID:      "service1",
+		Service: "redis",
+		Tags:    []string{"prod"},
+		Address: "1.1.1.1",
+		Port:    1111,
+	}
+	if err := s.EnsureService(2, "node1", service); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// The service exists
+	ns, err := s.NodeServices("node1")
+	if err != nil || ns == nil || len(ns.Services) != 1 {
+		t.Fatalf("bad: %#v (err: %#v)", ns, err)
+	}
+
+	// Delete the service
+	if err := s.DeleteNodeService(3, "node1", "service1"); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// The service doesn't exist.
+	ns, err = s.NodeServices("node1")
+	if err != nil || ns == nil || len(ns.Services) != 0 {
+		t.Fatalf("bad: %#v (err: %#v)", ns, err)
+	}
+}