ENG-4468: Always perform only one server rpc call for readiness check.

Summary:
Java client automatically retries (up to 100 times) on error return and overall timeout of 120sec.

Making the tserver readiness call only once with 5sec timeout, since it will return error when local bootstrap is happening. So the YW retry will check again as needed.

Test Plan: Jenkins: java-only

Reviewers: bogdan, neha

Reviewed By: neha

Subscribers: ybase

Differential Revision: https://phabricator.dev.yugabyte.com/D6344

java/yb-client/src/main/java/org/yb/client/AsyncYBClient.java

@@ -334,7 +334,10 @@ public Deferred<IsTabletServerReadyResponse> isTServerReady(final HostAndPort hp
       throw new IllegalStateException("Could not create a client to " + hp.toString());
     }
     IsTabletServerReadyRequest rpc = new IsTabletServerReadyRequest();
-    rpc.setTimeoutMillis(defaultAdminOperationTimeoutMs);
+    // TODO: Allow these two to be paramters in all such user API's.
+    rpc.maxAttempts = 1;
+    rpc.setTimeoutMillis(5000);
+
     Deferred<IsTabletServerReadyResponse> d = rpc.getDeferred();
     rpc.attempt++;
     client.sendRpc(rpc);
@@ -1159,13 +1162,13 @@ TabletClient clientFor(RemoteTablet tablet) {
   /**
    * Checks whether or not an RPC can be retried once more.
    * @param rpc The RPC we're going to attempt to execute.
-   * @return {@code true} if this RPC already had too many attempts,
+   * @return {@code true} if this RPC already had too many attempts or ran out of time,
    * {@code false} otherwise (in which case it's OK to retry once more).
    * @throws NonRecoverableException if the request has had too many attempts
    * already.
    */
   static boolean cannotRetryRequest(final YRpc<?> rpc) {
-    return rpc.deadlineTracker.timedOut() || rpc.attempt > 100;  // TODO Don't hardcode.
+    return rpc.deadlineTracker.timedOut() || rpc.attempt >= rpc.maxAttempts;
   }
 
   /**

java/yb-client/src/main/java/org/yb/client/YRpc.java

@@ -111,6 +111,9 @@ public interface HasKey {
    */
   byte attempt;  // package-private for TabletClient and AsyncYBClient only.
 
+  // Maximum number of attempts to try the RPC. Default 100 times.
+  byte maxAttempts = 100;
+
   // Whether or not retries for this RPC should always go to the same server. This is required in
   // some cases where we do not want the RPC retries to hit a different server serving the same
   // tablet.
@@ -242,6 +245,7 @@ public String toString() {
       buf.append(tablet.getTabletIdAsString());
     }
     buf.append(", attempt=").append(attempt);
+    buf.append(", maxAttempts=").append(maxAttempts);
     buf.append(", ").append(deadlineTracker);
     buf.append(", ").append(deferred);
     buf.append(')');