fix: close GRPC channel when we dispose of clients

dev/src/index.ts

@@ -374,7 +374,7 @@ export class Firestore {
 
     this._clientPool = new ClientPool(
       MAX_CONCURRENT_REQUESTS_PER_CLIENT,
-      () => {
+      /* clientFactory= */ () => {
         let client: GapicClient;
 
         if (this._settings.ssl === false) {
@@ -387,7 +387,8 @@ export class Firestore {
 
         logger('Firestore', null, 'Initialized Firestore GAPIC Client');
         return client;
-      }
+      },
+      /* clientDestructor= */ (client: GapicClient) => client.close()
     );
 
     logger('Firestore', null, 'Initialized Firestore');

dev/src/pool.ts

@@ -40,10 +40,14 @@ export class ClientPool<T> {
    * can handle.
    * @param clientFactory A factory function called as needed when new clients
    * are required.
+   * @param clientDestructor A cleanup function that is called when a client is
+   * disposed of.
    */
   constructor(
     private readonly concurrentOperationLimit: number,
-    private readonly clientFactory: () => T
+    private readonly clientFactory: () => T,
+    private readonly clientDestructor: (client: T) => Promise<void> = () =>
+      Promise.resolve()
   ) {}
 
   /**
@@ -88,15 +92,15 @@ export class ClientPool<T> {
    * removing it from the pool of active clients.
    * @private
    */
-  private release(requestTag: string, client: T): void {
+  private async release(requestTag: string, client: T): Promise<void> {
     let requestCount = this.activeClients.get(client) || 0;
     assert(requestCount > 0, 'No active request');
 
     requestCount = requestCount! - 1;
     this.activeClients.set(client, requestCount);
 
     if (requestCount === 0) {
-      const deletedCount = this.garbageCollect();
+      const deletedCount = await this.garbageCollect();
       if (deletedCount) {
         logger(
           'ClientPool.release',
@@ -147,12 +151,12 @@ export class ClientPool<T> {
     const client = this.acquire(requestTag);
 
     return op(client)
-      .catch(err => {
-        this.release(requestTag, client);
+      .catch(async err => {
+        await this.release(requestTag, client);
         return Promise.reject(err);
       })
-      .then(res => {
-        this.release(requestTag, client);
+      .then(async res => {
+        await this.release(requestTag, client);
         return res;
       });
   }
@@ -164,17 +168,20 @@ export class ClientPool<T> {
    * @return Number of clients deleted.
    * @private
    */
-  private garbageCollect(): number {
+  private async garbageCollect(): Promise<number> {
     let idleClients = 0;
-    this.activeClients.forEach((requestCount, client) => {
+    const cleanUpTasks: Array<Promise<void>> = [];
+    for (const [client, requestCount] of this.activeClients) {
       if (requestCount === 0) {
         ++idleClients;
 
         if (idleClients > 1) {
           this.activeClients.delete(client);
+          cleanUpTasks.push(this.clientDestructor(client));
         }
       }
-    });
+    }
+    await Promise.all(cleanUpTasks);
     return idleClients - 1;
   }
 }

dev/src/v1/firestore_admin_client_config.json

@@ -18,9 +18,9 @@
           "initial_retry_delay_millis": 100,
           "retry_delay_multiplier": 1.3,
           "max_retry_delay_millis": 60000,
-          "initial_rpc_timeout_millis": 20000,
+          "initial_rpc_timeout_millis": 60000,
           "rpc_timeout_multiplier": 1,
-          "max_rpc_timeout_millis": 20000,
+          "max_rpc_timeout_millis": 60000,
           "total_timeout_millis": 600000
         }
       },

dev/src/v1/firestore_client_config.json

@@ -18,9 +18,9 @@
           "initial_retry_delay_millis": 100,
           "retry_delay_multiplier": 1.3,
           "max_retry_delay_millis": 60000,
-          "initial_rpc_timeout_millis": 20000,
+          "initial_rpc_timeout_millis": 60000,
           "rpc_timeout_multiplier": 1,
-          "max_rpc_timeout_millis": 20000,
+          "max_rpc_timeout_millis": 60000,
           "total_timeout_millis": 600000
         }
       },

dev/src/v1beta1/firestore_client_config.json

@@ -13,9 +13,9 @@
           "initial_retry_delay_millis": 100,
           "retry_delay_multiplier": 1.3,
           "max_retry_delay_millis": 60000,
-          "initial_rpc_timeout_millis": 20000,
+          "initial_rpc_timeout_millis": 60000,
           "rpc_timeout_multiplier": 1,
-          "max_rpc_timeout_millis": 20000,
+          "max_rpc_timeout_millis": 60000,
           "total_timeout_millis": 600000
         }
       },

dev/test/pool.ts

@@ -150,6 +150,28 @@ describe('Client pool', () => {
     );
   });
 
+  it('garbage collection calls destructor', () => {
+    const garbageCollect = new Deferred();
+
+    const clientPool = new ClientPool<{}>(
+      1,
+      () => {
+        return {};
+      },
+      () => Promise.resolve(garbageCollect.resolve())
+    );
+
+    const operationPromises = deferredPromises(2);
+
+    // Create two pending operations that each spawn their own client
+    clientPool.run(REQUEST_TAG, () => operationPromises[0].promise);
+    clientPool.run(REQUEST_TAG, () => operationPromises[1].promise);
+
+    operationPromises.forEach(deferred => deferred.resolve());
+
+    return garbageCollect.promise;
+  });
+
   it('forwards success', () => {
     const clientPool = new ClientPool<{}>(1, () => {
       return {};