initial generator functions

agentcontrolSubAgent.go

@@ -19,6 +19,9 @@ type SubAgent struct {
 	// OIDs for Read/Write actions
 	OIDs []*PDUValueControlItem
 
+	OIDsGenerator       func() ([]*PDUValueControlItem, error)
+	OIDsSyncOnWalkStart bool
+
 	oidLock sync.Mutex
 
 	// UserErrorMarkPacket decides if shll treat user returned error as generr
@@ -34,6 +37,16 @@ func (t *SubAgent) SyncConfig() error {
 	t.oidLock.Lock()
 	defer t.oidLock.Unlock()
 
+	if t.OIDsGenerator != nil {
+		newoids, oiderr := t.OIDsGenerator()
+		if oiderr != nil {
+			t.Logger.Warnf("error generating oids, will not update main table: %s", oiderr.Error())
+		} else {
+			t.Logger.Info("updating oid table")
+			t.OIDs = newoids
+		}
+	}
+
 	t.Logger.Debugf("Total OIDs of %v: %v", t.CommunityIDs, len(t.OIDs))
 
 	for _, oid := range t.OIDs {
@@ -379,6 +392,9 @@ func (t *SubAgent) serveGetNextRequest(i *gosnmp.SnmpPacket) (*gosnmp.SnmpPacket
 				break
 			}
 		} else {
+			if t.OIDsSyncOnWalkStart && t.OIDsGenerator != nil {
+				t.SyncConfig()
+			}
 			before = false
 		}
 

snmpserver_test.go

@@ -235,6 +235,7 @@ func (suite *ServerTests) TestErrors() {
 }
 
 func (suite *ServerTests) TestGetSetOids() {
+	oids, _ := suite.getTestGetSetOIDS()
 	master := MasterAgent{
 		Logger: suite.Logger,
 		SecurityConfig: SecurityConfig{
@@ -252,7 +253,7 @@ func (suite *ServerTests) TestGetSetOids() {
 		SubAgents: []*SubAgent{
 			{
 				CommunityIDs: []string{"public"},
-				OIDs:         suite.getTestGetSetOIDS(),
+				OIDs:         oids,
 			},
 		},
 	}
@@ -430,7 +431,66 @@ func (suite *ServerTests) TestGetSetOids() {
 	<-stopWaitChain
 }
 
-func (suite *ServerTests) getTestGetSetOIDS() []*PDUValueControlItem {
+func (suite *ServerTests) TestGetWalkGeneratorOids() {
+	master := MasterAgent{
+		Logger: suite.Logger,
+		SecurityConfig: SecurityConfig{
+			AuthoritativeEngineBoots: 1,
+			Users: []gosnmp.UsmSecurityParameters{
+				{
+					UserName:                 "testUser",
+					AuthenticationProtocol:   gosnmp.MD5,
+					PrivacyProtocol:          gosnmp.DES,
+					AuthenticationPassphrase: "testAuth",
+					PrivacyPassphrase:        "testPriv",
+				},
+			},
+		},
+		SubAgents: []*SubAgent{
+			{
+				CommunityIDs:        []string{"public"},
+				OIDsGenerator:       suite.getTestGetSetOIDS,
+				OIDsSyncOnWalkStart: true,
+			},
+		},
+	}
+	shandle := NewSNMPServer(master)
+	shandle.ListenUDP("udp4", ":0")
+	var stopWaitChain = make(chan int)
+	go func() {
+		err := shandle.ServeForever()
+		if err != nil {
+			suite.Logger.Errorf("error in ServeForever: %v", err)
+		} else {
+			suite.Logger.Info("ServeForever Stoped.")
+		}
+		stopWaitChain <- 1
+
+	}()
+
+	serverAddress := shandle.Address().(*net.UDPAddr)
+	suite.Run("SNMPGetNext", func() {
+		result, err := getCmdOutput("snmpgetnext", "-v2c", "-c", "public",
+			serverAddress.String(), "1")
+		if err != nil {
+			suite.T().Errorf("cmd meet error: %+v", err)
+		}
+		lines := bytes.Split(bytes.TrimSpace(result), []byte("\n"))
+		assert.NotEqual(suite.T(), []byte{}, result, "data SNMPGetNext gets: \n%v", string(result))
+		assert.Equalf(suite.T(), 1, len(lines), "data SNMPGetNext gets: \n%v", string(result))
+	})
+	suite.Run("SNMPWalk", func() {
+		result, err := getCmdOutput("snmpwalk", "-v2c", "-c", "public",
+			serverAddress.String(), "1")
+		if err != nil {
+			suite.T().Errorf("cmd meet error: %+v", err)
+		}
+		lines := bytes.Split(bytes.TrimSpace(result), []byte("\n"))
+		assert.Equalf(suite.T(), len(master.SubAgents[0].OIDs)+1, len(lines), "data snmpwalk gets: \n%v", string(result))
+	})
+}
+
+func (suite *ServerTests) getTestGetSetOIDS() ([]*PDUValueControlItem, error) {
 	baseTestSuite := suite
 	return []*PDUValueControlItem{
 		{
@@ -601,7 +661,7 @@ func (suite *ServerTests) getTestGetSetOIDS() []*PDUValueControlItem {
 			},
 			Document: "TestTypeIPAddress",
 		},
-	}
+	}, nil
 }
 
 func (suite *ServerTests) TearDownSuite() {