Implement antctl agent-info

pkg/antctl/antctl.go

@@ -38,6 +38,10 @@ type transformedVersionResponse struct {
 	AntctlVersion                     string `json:"antctlVersion" yaml:"antctlVersion"`
 }
 
+type transformedAgentInfoResponse struct {
+	handlers.ComponentAgentInfoResponse `json:",inline" yaml:",inline"`
+}
+
 // versionTransform is the AddonTransform for the version command. This function
 // will try to parse the response as a ComponentVersionResponse and then populate
 // it with the version of antctl to a transformedVersionResponse object.
@@ -76,6 +80,19 @@ var CommandList = &commandList{
 			CommandGroup:        flat,
 			AddonTransform:      versionTransform,
 		},
+		{
+			Use:                 "agent-info",
+			Short:               "Print agent's basic information",
+			Long:                "Print agent's basic information including some connections and node subnet.",
+			HandlerFactory:      new(handlers.AgentInfo),
+			GroupVersion:        &systemGroup,
+			TransformedResponse: reflect.TypeOf(transformedAgentInfoResponse{}),
+			Agent:               true,
+			Controller:          false,
+			SingleObject:        true,
+			CommandGroup:        flat,
+			AddonTransform:      nil,
+		},
 	},
 	codec: scheme.Codecs,
 }

pkg/antctl/handlers/agentinfo.go

@@ -0,0 +1,58 @@
+// Copyright 2020 Antrea Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package handlers
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"k8s.io/klog"
+
+	"github.com/vmware-tanzu/antrea/pkg/monitor"
+)
+
+var _ Factory = new(AgentInfo)
+
+// ComponentAgentInfoResponse describes the internal response struct of agent-info command.
+// The first three fields refer to connection between the agent and controller, OVSDB and
+// openflow. Subnet refers to the subnet range from the Pod CIDR allocated to the Node.
+type ComponentAgentInfoResponse struct {
+	ControllerConn monitor.ConnStatus `json:"controllerConn,omitempty" yaml:"controllerConn,omitempty"`
+	OVSDBConn      monitor.ConnStatus `json:"ovsdbConn,omitempty" yaml:"ovsdbConn,omitempty"`
+	OFConn         monitor.ConnStatus `json:"ofConn,omitempty" yaml:"ofConn,omitempty"`
+	Subnet         string             `json:"subnet,omitempty" yaml:"subnet,omitempty"`
+}
+
+// AgentInfo is the implementation of the Factory interface for the agent-info command.
+type AgentInfo struct{}
+
+// Handler returns the function which can handle queries issued by agent-info commands,
+// the handler function populate component's agent-info to the ComponentAgentInfoResponse.
+func (v *AgentInfo) Handler(aq monitor.AgentQuerier, cq monitor.ControllerQuerier) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		var m ComponentAgentInfoResponse
+		if aq != nil {
+			m.ControllerConn = aq.GetControllerConnection()
+			m.OVSDBConn = aq.GetOVSDBConnection()
+			m.OFConn = aq.GetOFConnection()
+			m.Subnet = aq.GetNodeSubnet()
+		}
+		err := json.NewEncoder(w).Encode(m)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			klog.Errorf("Error when encoding ComponentAgentInfoResponse to json: %v", err)
+		}
+	}
+}

pkg/antctl/handlers/agentinfo_test.go

@@ -0,0 +1,65 @@
+// Copyright 2020 Antrea Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package handlers
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	monitor "github.com/vmware-tanzu/antrea/pkg/monitor"
+	mockmonitor "github.com/vmware-tanzu/antrea/pkg/monitor/testing"
+
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAgentInfo(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	testcases := map[string]struct {
+		controllerConn     monitor.ConnStatus
+		ovsdbConn          monitor.ConnStatus
+		ofConn             monitor.ConnStatus
+		subnet             string
+		expectedOutput     string
+		expectedStatusCode int
+	}{
+		"AgentInfo": {
+			controllerConn:     monitor.ConnStatusUp,
+			ovsdbConn:          monitor.ConnStatusUp,
+			ofConn:             monitor.ConnStatusUp,
+			subnet:             "192.168.1.0/24",
+			expectedOutput:     "{\"controllerConn\":\"UP\",\"ovsdbConn\":\"UP\",\"ofConn\":\"UP\",\"subnet\":\"192.168.1.0/24\"}\n",
+			expectedStatusCode: http.StatusOK,
+		},
+	}
+	for k, tc := range testcases {
+		t.Run(k, func(t *testing.T) {
+			req, err := http.NewRequest("GET", "/", nil)
+			assert.Nil(t, err)
+			recorder := httptest.NewRecorder()
+			aq := mockmonitor.NewMockAgentQuerier(ctrl)
+			aq.EXPECT().GetControllerConnection().Return(tc.controllerConn)
+			aq.EXPECT().GetOVSDBConnection().Return(tc.ovsdbConn)
+			aq.EXPECT().GetOFConnection().Return(tc.ofConn)
+			aq.EXPECT().GetNodeSubnet().Return(tc.subnet)
+			new(AgentInfo).Handler(aq, nil).ServeHTTP(recorder, req)
+			assert.Equal(t, tc.expectedStatusCode, recorder.Code, k)
+			assert.Equal(t, tc.expectedOutput, recorder.Body.String(), k)
+		})
+	}
+}

pkg/monitor/querier.go

@@ -33,6 +33,13 @@ const (
 	nodeName     = "NODE_NAME"
 )
 
+type ConnStatus string
+
+const (
+	ConnStatusUp   ConnStatus = "UP"
+	ConnStatusDown ConnStatus = "DOWN"
+)
+
 // Querier provides interface for both monitor CRD and CLI to consume controller and agent status.
 type Querier interface {
 	GetSelfPod() v1.ObjectReference
@@ -45,6 +52,10 @@ type AgentQuerier interface {
 	Querier
 	GetOVSFlowTable() map[string]int32
 	GetLocalPodNum() int32
+	GetOVSDBConnection() ConnStatus
+	GetOFConnection() ConnStatus
+	GetControllerConnection() ConnStatus
+	GetNodeSubnet() string
 }
 
 type ControllerQuerier interface {
@@ -151,6 +162,35 @@ func (monitor *agentMonitor) GetAgentConditions(ovsConnected bool) []v1beta1.Age
 	}
 }
 
+// GetOVSDBConnection tells if OVSDB is connected.
+func (monitor *agentMonitor) GetOVSDBConnection() ConnStatus {
+	if _, err := monitor.ovsBridgeClient.GetOVSVersion(); err != nil {
+		return ConnStatusDown
+	}
+	return ConnStatusUp
+}
+
+// GetOFConnection tells if openflow is connected.
+func (monitor *agentMonitor) GetOFConnection() ConnStatus {
+	if monitor.ofClient.IsConnected() {
+		return ConnStatusUp
+	}
+	return ConnStatusDown
+}
+
+// GetControllerConnection tells if controller is connected.
+func (monitor *agentMonitor) GetControllerConnection() ConnStatus {
+	if !monitor.networkPolicyInfoQuerier.GetControllerConnectionStatus() {
+		return ConnStatusDown
+	}
+	return ConnStatusUp
+}
+
+// GetNodeSubnet gets the node subnet.
+func (monitor *agentMonitor) GetNodeSubnet() string {
+	return monitor.nodeSubnet
+}
+
 func (monitor *agentMonitor) GetVersion() string {
 	return version.GetFullVersion()
 }