http: adding the drain toggle endpoint

command/agent/node_endpoint.go

@@ -84,7 +84,7 @@ func (s *HTTPServer) nodeAllocations(resp http.ResponseWriter, req *http.Request
 }
 
 func (s *HTTPServer) nodeToggleDrain(resp http.ResponseWriter, req *http.Request,
-	jobName string) (interface{}, error) {
+	nodeID string) (interface{}, error) {
 	if req.Method != "PUT" && req.Method != "POST" {
 		return nil, CodedError(405, ErrInvalidMethod)
 	}
@@ -99,8 +99,18 @@ func (s *HTTPServer) nodeToggleDrain(resp http.ResponseWriter, req *http.Request
 		return nil, CodedError(400, "invalid enable value")
 	}
 
-	// TODO
-	return nil, nil
+	args := structs.NodeUpdateDrainRequest{
+		NodeID: nodeID,
+		Drain:  enable,
+	}
+	s.parseRegion(req, &args.Region)
+
+	var out structs.NodeDrainUpdateResponse
+	if err := s.agent.RPC("Client.UpdateDrain", &args, &out); err != nil {
+		return nil, err
+	}
+	setIndex(resp, out.Index)
+	return out, nil
 }
 
 func (s *HTTPServer) nodeQuery(resp http.ResponseWriter, req *http.Request,

command/agent/node_endpoint_test.go

@@ -158,6 +158,54 @@ func TestHTTP_NodeAllocations(t *testing.T) {
 	})
 }
 
+func TestHTTP_NodeDrain(t *testing.T) {
+	httpTest(t, nil, func(s *TestServer) {
+		// Create the node
+		node := mock.Node()
+		args := structs.NodeRegisterRequest{
+			Node:         node,
+			WriteRequest: structs.WriteRequest{Region: "region1"},
+		}
+		var resp structs.NodeUpdateResponse
+		if err := s.Agent.RPC("Client.Register", &args, &resp); err != nil {
+			t.Fatalf("err: %v", err)
+		}
+
+		// Directly manipulate the state
+		state := s.Agent.server.State()
+		alloc1 := mock.Alloc()
+		alloc1.NodeID = node.ID
+		err := state.UpdateAllocations(1000, []*structs.Allocation{alloc1})
+		if err != nil {
+			t.Fatalf("err: %v", err)
+		}
+
+		// Make the HTTP request
+		req, err := http.NewRequest("POST", "/v1/node/"+node.ID+"/drain?enable=1", nil)
+		if err != nil {
+			t.Fatalf("err: %v", err)
+		}
+		respW := httptest.NewRecorder()
+
+		// Make the request
+		obj, err := s.Server.NodeSpecificRequest(respW, req)
+		if err != nil {
+			t.Fatalf("err: %v", err)
+		}
+
+		// Check for the index
+		if respW.HeaderMap.Get("X-Nomad-Index") == "" {
+			t.Fatalf("missing index")
+		}
+
+		// Check the response
+		upd := obj.(structs.NodeDrainUpdateResponse)
+		if len(upd.EvalIDs) == 0 {
+			t.Fatalf("bad: %v", upd)
+		}
+	})
+}
+
 func TestHTTP_NodeQuery(t *testing.T) {
 	httpTest(t, nil, func(s *TestServer) {
 		// Create the job