fix: reconnect breaks async requests

lib/src/main/java/io/ably/lib/http/AsyncHttpScheduler.java

@@ -33,16 +33,23 @@ public AsyncHttpScheduler exchangeHttpCore(HttpCore httpCore) {
         return new AsyncHttpScheduler(httpCore, this.executor);
     }
 
+    public void connect() {
+        ((CloseableThreadPoolExecutor) executor).connect();
+    }
+
     private static class CloseableThreadPoolExecutor implements CloseableExecutor {
-        private final ThreadPoolExecutor executor;
+        // can be accessed by multiple threads, so needs to be volatile
+        private volatile ThreadPoolExecutor executor;
+        private final ClientOptions options;
 
         CloseableThreadPoolExecutor(final ClientOptions options) {
+            this.options = options;
             executor = new ThreadPoolExecutor(
                 options.asyncHttpThreadpoolSize,
                 options.asyncHttpThreadpoolSize,
                 KEEP_ALIVE_TIME,
                 TimeUnit.MILLISECONDS,
-                new LinkedBlockingQueue<Runnable>()
+                new LinkedBlockingQueue<>()
             );
         }
 
@@ -59,9 +66,16 @@ public void close() throws Exception {
             }
         }
 
-        @Override
-        protected void finalize() throws Throwable {
-            close();
+        public void connect() {
+            if (executor.isShutdown()) {
+                executor = new ThreadPoolExecutor(
+                    options.asyncHttpThreadpoolSize,
+                    options.asyncHttpThreadpoolSize,
+                    KEEP_ALIVE_TIME,
+                    TimeUnit.MILLISECONDS,
+                    new LinkedBlockingQueue<>()
+                );
+            }
         }
     }
 }

lib/src/main/java/io/ably/lib/http/Http.java

@@ -21,6 +21,10 @@ public void close() throws Exception {
         asyncHttp.close();
     }
 
+    public void connect() {
+        asyncHttp.connect();
+    }
+
     /**
      * [Internal Method]
      * <p>

lib/src/main/java/io/ably/lib/realtime/AblyRealtime.java

@@ -96,7 +96,9 @@ public AblyRealtime(ClientOptions options) throws AblyException {
      * <p>
      * Spec: RTN11
      */
+    @Override
     public void connect() {
+        super.connect(); // resets thread pool for async requests
         connection.connect();
     }
 

lib/src/main/java/io/ably/lib/rest/AblyBase.java

@@ -138,6 +138,13 @@ public void close() throws Exception {
         http.close();
     }
 
+    /**
+     * Internal method, used for `RealtimeClient` only
+     */
+    protected void connect() {
+        http.connect();
+    }
+
     /**
      * A collection of Channels associated with an Ably instance.
      */

lib/src/test/java/io/ably/lib/test/realtime/RealtimeConnectTest.java

@@ -6,6 +6,9 @@
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
+import io.ably.lib.test.common.Helpers;
+import io.ably.lib.types.AsyncHttpPaginatedResponse;
+import io.ably.lib.types.ErrorInfo;
 import org.junit.Ignore;
 import org.junit.Test;
 
@@ -23,6 +26,8 @@
 import io.ably.lib.types.ProtocolMessage;
 import org.junit.rules.Timeout;
 
+import java.util.concurrent.atomic.AtomicLong;
+
 public class RealtimeConnectTest extends ParameterizedTest {
 
     public Timeout testTimeout = Timeout.seconds(30);
@@ -248,4 +253,35 @@ public void close_when_connecting() {
         }
     }
 
+    @Test
+    public void reopened_connection_rest_works() throws Exception {
+        try (AblyRealtime realtimeClient = new AblyRealtime(createOptions(testVars.keys[0].keyStr))) {
+            realtimeClient.close();
+            realtimeClient.connect();
+
+            long timestamp = System.currentTimeMillis();
+            AtomicLong ablyTime = new AtomicLong(0);
+            Helpers.CompletionWaiter waiter = new Helpers.CompletionWaiter();
+
+            realtimeClient.requestAsync("GET", "/time", null, null, null, new AsyncHttpPaginatedResponse.Callback() {
+                @Override
+                public void onResponse(AsyncHttpPaginatedResponse response) {
+                    ablyTime.set(response.items()[0].getAsLong());
+                    waiter.onSuccess();
+                }
+
+                @Override
+                public void onError(ErrorInfo reason) {
+                    waiter.onError(reason);
+                }
+            });
+
+            waiter.waitFor();
+
+            long thirtySeconds = 30_000L;
+
+            assertTrue(ablyTime.get() > timestamp - thirtySeconds && ablyTime.get() < timestamp + thirtySeconds);
+        }
+    }
+
 }