feat(NODE-6882): close checked out connection in MongoClient.close()

Author: nbbeeken

src/cmap/connection_pool.ts

@@ -17,6 +17,7 @@ import {
 } from '../constants';
 import {
   type AnyError,
+  ConnectionPoolClosedError,
   type MongoError,
   MongoInvalidArgumentError,
   MongoMissingCredentialsError,
@@ -489,6 +490,16 @@ export class ConnectionPool extends TypedEventEmitter<ConnectionPoolEvents> {
     }
   }
 
+  closeCheckedOutConnections() {
+    for (const conn of this.checkedOut) {
+      this.emitAndLog(
+        ConnectionPool.CONNECTION_CLOSED,
+        new ConnectionClosedEvent(this, conn, 'poolClosed')
+      );
+      conn.onError(new ConnectionPoolClosedError());
+    }
+  }
+
   /** Close the pool */
   close(): void {
     if (this.closed) {

src/error.ts

@@ -1018,6 +1018,62 @@ export class MongoTopologyClosedError extends MongoAPIError {
   }
 }
 
+/**
+ * An error generated when the MongoClient is closed and async
+ * operations are interrupted.
+ *
+ * @public
+ * @category Error
+ */
+export class MongoClientClosedError extends MongoAPIError {
+  /**
+   * **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(message = 'MongoClient is closed') {
+    super(message);
+  }
+
+  override get name(): string {
+    return 'MongoClientClosedError';
+  }
+}
+
+/**
+ * An error generated when a ConnectionPool is closed and async
+ * operations are interrupted.
+ *
+ * @public
+ * @category Error
+ */
+export class ConnectionPoolClosedError extends MongoAPIError {
+  /**
+   * **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(message = 'ConnectionPool is closed') {
+    super(message);
+  }
+
+  override get name(): string {
+    return 'ConnectionPoolClosedError';
+  }
+}
+
 /** @public */
 export interface MongoNetworkErrorOptions {
   /** Indicates the timeout happened before a connection handshake completed */

src/mongo_client.ts

@@ -672,6 +672,8 @@ export class MongoClient extends TypedEventEmitter<MongoClientEvents> implements
       writable: false
     });
 
+    this.topology?.closeCheckedOutConnections();
+
     const activeCursorCloses = Array.from(this.s.activeCursors, cursor => cursor.close());
     this.s.activeCursors.clear();
 

src/sdam/server.ts

@@ -246,8 +246,12 @@ export class Server extends TypedEventEmitter<ServerEvents> {
     }
   }
 
+  closeCheckedOutConnections() {
+    return this.pool.closeCheckedOutConnections();
+  }
+
   /** Destroy the server connection */
-  destroy(): void {
+  close(): void {
     if (this.s.state === STATE_CLOSED) {
       return;
     }

src/sdam/topology.ts

@@ -490,14 +490,20 @@ export class Topology extends TypedEventEmitter<TopologyEvents> {
     }
   }
 
+  closeCheckedOutConnections() {
+    for (const server of this.s.servers.values()) {
+      return server.closeCheckedOutConnections();
+    }
+  }
+
   /** Close this topology */
   close(): void {
     if (this.s.state === STATE_CLOSED || this.s.state === STATE_CLOSING) {
       return;
     }
 
     for (const server of this.s.servers.values()) {
-      destroyServer(server, this);
+      closeServer(server, this);
     }
 
     this.s.servers.clear();
@@ -791,12 +797,12 @@ export class Topology extends TypedEventEmitter<TopologyEvents> {
 }
 
 /** Destroys a server, and removes all event listeners from the instance */
-function destroyServer(server: Server, topology: Topology) {
+function closeServer(server: Server, topology: Topology) {
   for (const event of LOCAL_SERVER_EVENTS) {
     server.removeAllListeners(event);
   }
 
-  server.destroy();
+  server.close();
   topology.emitAndLog(
     Topology.SERVER_CLOSED,
     new ServerClosedEvent(topology.s.id, server.description.address)
@@ -903,7 +909,7 @@ function updateServers(topology: Topology, incomingServerDescription?: ServerDes
 
     // prepare server for garbage collection
     if (server) {
-      destroyServer(server, topology);
+      closeServer(server, topology);
     }
   }
 }