feat(NODE-6605): add error message when invalidating primary

src/error.ts

@@ -1,10 +1,10 @@
-import type { Document } from './bson';
+import type { Document, ObjectId } from './bson';
 import {
   type ClientBulkWriteError,
   type ClientBulkWriteResult
 } from './operations/client_bulk_write/common';
 import type { ServerType } from './sdam/common';
-import type { TopologyVersion } from './sdam/server_description';
+import type { ServerDescription, TopologyVersion } from './sdam/server_description';
 import type { TopologyDescription } from './sdam/topology_description';
 
 /** @public */
@@ -340,6 +340,41 @@ export class MongoRuntimeError extends MongoDriverError {
   }
 }
 
+/**
+ * An error generated when a primary server is marked stale, never directly thrown
+ *
+ * @public
+ * @category Error
+ */
+export class MongoStalePrimaryError extends MongoRuntimeError {
+  /**
+   * **Do not use this constructor!**
+   *
+   * Meant for internal use only.
+   *
+   * @remarks
+   * This class is only meant to be constructed within the driver. This constructor is
+   * not subject to semantic versioning compatibility guarantees and may change at any time.
+   *
+   * @public
+   **/
+  constructor(
+    serverDescription: ServerDescription,
+    maxSetVersion: number | null,
+    maxElectionId: ObjectId | null,
+    options?: { cause?: Error }
+  ) {
+    super(
+      `primary marked stale due to electionId/setVersion mismatch: server setVersion: ${serverDescription.setVersion}, server electionId: ${serverDescription.electionId}, topology setVersion: ${maxSetVersion}, topology electionId: ${maxElectionId}`,
+      options
+    );
+  }
+
+  override get name(): string {
+    return 'MongoStalePrimaryError';
+  }
+}
+
 /**
  * An error generated when a batch command is re-executed after one of the commands in the batch
  * has failed

src/index.ts

@@ -77,6 +77,7 @@ export {
   MongoServerClosedError,
   MongoServerError,
   MongoServerSelectionError,
+  MongoStalePrimaryError,
   MongoSystemError,
   MongoTailableCursorError,
   MongoTopologyClosedError,

src/sdam/server_description.ts

@@ -112,7 +112,10 @@ export class ServerDescription {
     this.minRoundTripTime = options?.minRoundTripTime ?? 0;
     this.lastUpdateTime = now();
     this.lastWriteDate = hello?.lastWrite?.lastWriteDate ?? 0;
+    // NOTE: This actually builds the stack string instead of holding onto the getter and all its
+    // associated references. This is done to prevent a memory leak.
     this.error = options.error ?? null;
+    this.error?.stack;
     // TODO(NODE-2674): Preserve int64 sent from MongoDB
     this.topologyVersion = this.error?.topologyVersion ?? hello?.topologyVersion ?? null;
     this.setName = hello?.setName ?? null;

src/sdam/topology_description.ts

@@ -1,6 +1,6 @@
 import { EJSON, type ObjectId } from '../bson';
 import * as WIRE_CONSTANTS from '../cmap/wire_protocol/constants';
-import { type MongoError, MongoRuntimeError } from '../error';
+import { type MongoError, MongoRuntimeError, MongoStalePrimaryError } from '../error';
 import { compareObjectId, shuffle } from '../utils';
 import { ServerType, TopologyType } from './common';
 import { ServerDescription } from './server_description';
@@ -400,7 +400,9 @@ function updateRsFromPrimary(
       // replace serverDescription with a default ServerDescription of type "Unknown"
       serverDescriptions.set(
         serverDescription.address,
-        new ServerDescription(serverDescription.address)
+        new ServerDescription(serverDescription.address, undefined, {
+          error: new MongoStalePrimaryError(serverDescription, maxSetVersion, maxElectionId)
+        })
       );
 
       return [checkHasPrimary(serverDescriptions), setName, maxSetVersion, maxElectionId];
@@ -416,7 +418,9 @@ function updateRsFromPrimary(
           // this primary is stale, we must remove it
           serverDescriptions.set(
             serverDescription.address,
-            new ServerDescription(serverDescription.address)
+            new ServerDescription(serverDescription.address, undefined, {
+              error: new MongoStalePrimaryError(serverDescription, maxSetVersion, maxElectionId)
+            })
           );
 
           return [checkHasPrimary(serverDescriptions), setName, maxSetVersion, maxElectionId];
@@ -438,7 +442,12 @@ function updateRsFromPrimary(
   for (const [address, server] of serverDescriptions) {
     if (server.type === ServerType.RSPrimary && server.address !== serverDescription.address) {
       // Reset old primary's type to Unknown.
-      serverDescriptions.set(address, new ServerDescription(server.address));
+      serverDescriptions.set(
+        address,
+        new ServerDescription(server.address, undefined, {
+          error: new MongoStalePrimaryError(serverDescription, maxSetVersion, maxElectionId)
+        })
+      );
 
       // There can only be one primary
       break;

test/spec/server-discovery-and-monitoring/rs/new_primary_new_electionid.json

@@ -76,7 +76,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",
@@ -123,7 +124,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/new_primary_new_electionid.yml

@@ -63,7 +63,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId: ,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",
@@ -100,7 +101,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/new_primary_new_setversion.json

@@ -76,7 +76,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",
@@ -123,7 +124,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/new_primary_new_setversion.yml

@@ -63,7 +63,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",
@@ -100,7 +101,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/null_election_id-pre-6.0.json

@@ -66,7 +66,7 @@
               "$oid": "000000000000000000000002"
             },
             "minWireVersion": 0,
-            "maxWireVersion": 21
+            "maxWireVersion": 7
           }
         ]
       ],

test/spec/server-discovery-and-monitoring/rs/primary_disconnect_electionid.json

@@ -48,7 +48,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/primary_disconnect_electionid.yml

@@ -36,7 +36,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/primary_disconnect_setversion.json

@@ -48,7 +48,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/primary_disconnect_setversion.yml

@@ -36,7 +36,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/setversion_greaterthan_max_without_electionid.json

@@ -65,7 +65,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/setversion_greaterthan_max_without_electionid.yml

@@ -61,7 +61,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/setversion_without_electionid-pre-6.0.json

@@ -65,7 +65,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/setversion_without_electionid-pre-6.0.yml

@@ -61,7 +61,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/use_setversion_without_electionid-pre-6.0.json

@@ -73,7 +73,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",
@@ -117,7 +118,8 @@
           "a:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           },
           "b:27017": {
             "type": "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/use_setversion_without_electionid-pre-6.0.yml

@@ -62,7 +62,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",
@@ -99,7 +100,8 @@ phases: [
                 "a:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 },
                 "b:27017": {
                     type: "RSPrimary",

test/spec/server-discovery-and-monitoring/rs/use_setversion_without_electionid.json

@@ -81,7 +81,8 @@
           "b:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           }
         },
         "topologyType": "ReplicaSetWithPrimary",
@@ -128,7 +129,8 @@
           "b:27017": {
             "type": "Unknown",
             "setName": null,
-            "electionId": null
+            "electionId": null,
+            "error": "primary marked stale due to electionId/setVersion mismatch"
           }
         },
         "topologyType": "ReplicaSetWithPrimary",

test/spec/server-discovery-and-monitoring/rs/use_setversion_without_electionid.yml

@@ -68,7 +68,8 @@ phases: [
                 "b:27017": {
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 }
             },
             topologyType: "ReplicaSetWithPrimary",
@@ -106,7 +107,8 @@ phases: [
                 "b:27017":{
                     type: "Unknown",
                     setName: ,
-                    electionId:
+                    electionId:,
+                    error: "primary marked stale due to electionId/setVersion mismatch"
                 }
             },
             topologyType: "ReplicaSetWithPrimary",