feat(NODE-3424): use hello for monitoring commands

Author: nbbeeken

lib/core/connection/connect.js

@@ -113,6 +113,10 @@ function performInitialHandshake(conn, options, _callback) {
         response.ismaster = response.isWritablePrimary;
       }
 
+      if (response.helloOk) {
+        conn.helloOk = true;
+      }
+
       const supportedServerErr = checkSupportedServer(response, options);
       if (supportedServerErr) {
         callback(supportedServerErr);
@@ -169,6 +173,7 @@ function prepareHandshakeDocument(authContext, callback) {
 
   const handshakeDoc = {
     [serverApi ? 'hello' : 'ismaster']: true,
+    helloOk: true,
     client: options.metadata || makeClientMetadata(options),
     compression: compressors
   };

lib/core/connection/connection.js

@@ -95,6 +95,7 @@ class Connection extends EventEmitter {
     this.port = options.port || 27017;
     this.host = options.host || 'localhost';
     this.socketTimeout = typeof options.socketTimeout === 'number' ? options.socketTimeout : 0;
+    this.helloOk = undefined;
 
     // These values are inspected directly in tests, but maybe not necessary to keep around
     this.keepAlive = typeof options.keepAlive === 'boolean' ? options.keepAlive : true;

lib/core/sdam/monitor.js

@@ -204,9 +204,10 @@ function checkServer(monitor, callback) {
     const maxAwaitTimeMS = monitor.options.heartbeatFrequencyMS;
     const topologyVersion = monitor[kServer].description.topologyVersion;
     const isAwaitable = topologyVersion != null;
-    const serverApi = monitor[kConnection].serverApi;
+    const serverApi = monitor[kConnection].serverApi && monitor[kConnection].serverApi;
+    const helloOk = monitor[kConnection].helloOk;
 
-    const cmd = { [serverApi ? 'hello' : 'ismaster']: true };
+    const cmd = { [serverApi || helloOk ? 'hello' : 'ismaster']: true };
     const options = { socketTimeout: connectTimeoutMS };
 
     if (isAwaitable) {

lib/core/sdam/server_description.js

@@ -180,7 +180,7 @@ function parseServerType(ismaster) {
   if (ismaster.setName) {
     if (ismaster.hidden) {
       return ServerType.RSOther;
-    } else if (ismaster.ismaster) {
+    } else if (ismaster.ismaster || ismaster.isWritablePrimary) {
       return ServerType.RSPrimary;
     } else if (ismaster.secondary) {
       return ServerType.RSSecondary;

lib/core/topologies/replset_state.js

@@ -218,7 +218,8 @@ const isArbiter = ismaster => ismaster.arbiterOnly && ismaster.setName;
 ReplSetState.prototype.update = function(server) {
   var self = this;
   // Get the current ismaster
-  var ismaster = server.lastIsMaster();
+  const ismaster = server.lastIsMaster();
+  const isWritablePrimary = ismaster && (ismaster.ismaster || ismaster.isWritablePrimary);
 
   // Get the server name and lowerCase it
   var serverName = server.name.toLowerCase();
@@ -334,7 +335,7 @@ ReplSetState.prototype.update = function(server) {
   if (
     (ismaster.setName && ismaster.hidden) ||
     (ismaster.setName &&
-      !ismaster.ismaster &&
+      !isWritablePrimary &&
       !ismaster.secondary &&
       !ismaster.arbiterOnly &&
       !ismaster.passive)
@@ -357,7 +358,7 @@ ReplSetState.prototype.update = function(server) {
   //
   // Standalone server, destroy and return
   //
-  if (ismaster && ismaster.ismaster && !ismaster.setName) {
+  if (ismaster && isWritablePrimary && !ismaster.setName) {
     this.topologyType = this.primary ? TopologyType.ReplicaSetWithPrimary : TopologyType.Unknown;
     this.remove(server, { force: true });
     return false;
@@ -366,7 +367,7 @@ ReplSetState.prototype.update = function(server) {
   //
   // Server in maintanance mode
   //
-  if (ismaster && !ismaster.ismaster && !ismaster.secondary && !ismaster.arbiterOnly) {
+  if (ismaster && !isWritablePrimary && !ismaster.secondary && !ismaster.arbiterOnly) {
     this.remove(server, { force: true });
     return false;
   }
@@ -418,7 +419,7 @@ ReplSetState.prototype.update = function(server) {
   //
   // Primary handling
   //
-  if (!this.primary && ismaster.ismaster && ismaster.setName) {
+  if (!this.primary && isWritablePrimary && ismaster.setName) {
     var ismasterElectionId = server.lastIsMaster().electionId;
     if (this.setName && this.setName !== ismaster.setName) {
       this.topologyType = TopologyType.ReplicaSetNoPrimary;
@@ -481,7 +482,7 @@ ReplSetState.prototype.update = function(server) {
 
     emitTopologyDescriptionChanged(self);
     return true;
-  } else if (ismaster.ismaster && ismaster.setName) {
+  } else if (isWritablePrimary && ismaster.setName) {
     // Get the electionIds
     var currentElectionId = self.set[self.primary.name.toLowerCase()].electionId;
     var currentSetVersion = self.set[self.primary.name.toLowerCase()].setVersion;

lib/core/topologies/shared.js

@@ -109,10 +109,12 @@ var getTopologyType = function(self, ismaster) {
     ismaster = self.ismaster;
   }
 
+  const isWritablePrimary = ismaster && (ismaster.ismaster || ismaster.isWritablePrimary);
+
   if (!ismaster) return 'Unknown';
-  if (ismaster.ismaster && ismaster.msg === 'isdbgrid') return 'Mongos';
-  if (ismaster.ismaster && !ismaster.hosts) return 'Standalone';
-  if (ismaster.ismaster) return 'RSPrimary';
+  if (isWritablePrimary && ismaster.msg === 'isdbgrid') return 'Mongos';
+  if (isWritablePrimary && !ismaster.hosts) return 'Standalone';
+  if (isWritablePrimary) return 'RSPrimary';
   if (ismaster.secondary) return 'RSSecondary';
   if (ismaster.arbiterOnly) return 'RSArbiter';
   return 'Unknown';

test/functional/core/replset_state.test.js

@@ -22,7 +22,8 @@ describe('ReplicaSet state', function() {
           description.match(/replicaSet URI option causes starting topology to be RSNP/) ||
           description.match(/Discover secondary with directConnection URI option/) ||
           description.match(/Discover ghost with directConnection URI option/) ||
-          description.match(/topologyVersion/)
+          description.match(/topologyVersion/) ||
+          description.match(/Repeated isWritablePrimary response must be processed/)
         ) {
           this.skip();
           return;