Support ApolloClient#stop for safe client disposal.

package.json

@@ -34,7 +34,7 @@
     {
       "name": "apollo-client",
       "path": "./packages/apollo-client/lib/bundle.min.js",
-      "maxSize": "9.3 kB"
+      "maxSize": "9.4 kB"
     },
     {
       "name": "apollo-utilities",

packages/apollo-client/src/ApolloClient.ts

@@ -219,6 +219,17 @@ export default class ApolloClient<TCacheShape> implements DataProxy {
       this.clientAwareness.version = clientAwarenessVersion;
     }
   }
+
+  /**
+   * Call this method to terminate any active client processes, making it safe
+   * to dispose of this ApolloClient instance.
+   */
+  public stop() {
+    if (this.queryManager) {
+      this.queryManager.stop();
+    }
+  }
+
   /**
    * This watches the cache store of the query according to the options specified and
    * returns an {@link ObservableQuery}. We can subscribe to this {@link ObservableQuery} and

packages/apollo-client/src/core/QueryManager.ts

@@ -107,6 +107,17 @@ export class QueryManager<TStore> {
     this.scheduler = new QueryScheduler({ queryManager: this, ssrMode });
   }
 
+  /**
+   * Call this method to terminate any active query processes, making it safe
+   * to dispose of this QueryManager instance.
+   */
+  public stop() {
+    this.scheduler.stop();
+    this.fetchQueryRejectFns.forEach(reject => {
+      reject(new Error('QueryManager stopped while query was in flight'));
+    });
+  }
+
   public mutate<T>({
     mutation,
     variables,

packages/apollo-client/src/scheduler/scheduler.ts

@@ -50,6 +50,21 @@ export class QueryScheduler<TCacheShape> {
     this.ssrMode = ssrMode || false;
   }
 
+  /**
+   * Call this method to terminate any active scheduler timers, making it safe
+   * to dispose of this QueryScheduler instance.
+   */
+  public stop() {
+    Object.keys(this.registeredQueries).forEach(queryId => {
+      this.stopPollingQuery(queryId);
+    });
+    // After calling this.stopPollingQuery for all registered queries, calling
+    // fetchQueriesOnInterval will remove the corresponding intervals.
+    Object.keys(this.intervalQueries).forEach(interval => {
+      this.fetchQueriesOnInterval(+interval);
+    });
+  }
+
   public checkInFlight(queryId: string) {
     const query = this.queryManager.queryStore.get(queryId);