chore: unflake SavepointMockServerTest (#3237)

* chore: unflake SavepointMockServerTest

* fix: use separate tag to verify no keep-alive requests

Author: olavloite

google-cloud-spanner/src/main/java/com/google/cloud/spanner/connection/ReadWriteTransaction.java

@@ -461,7 +461,10 @@ public void run() {
                 CallType.SYNC,
                 SELECT1_STATEMENT,
                 AnalyzeMode.NONE,
-                Options.tag("connection.transaction-keep-alive"));
+                Options.tag(
+                    System.getProperty(
+                        "spanner.connection.keep_alive_query_tag",
+                        "connection.transaction-keep-alive")));
         future.addListener(
             ReadWriteTransaction.this::maybeScheduleKeepAlivePing, MoreExecutors.directExecutor());
       }

google-cloud-spanner/src/test/java/com/google/cloud/spanner/connection/SavepointMockServerTest.java

@@ -682,77 +682,57 @@ public void testRollbackToSavepointWithoutInternalRetriesInReadOnlyTransaction()
 
   @Test
   public void testKeepAlive() throws InterruptedException, TimeoutException {
+    String keepAliveTag = "test_keep_alive_tag";
     System.setProperty("spanner.connection.keep_alive_interval_millis", "1");
+    System.setProperty("spanner.connection.keep_alive_query_tag", keepAliveTag);
     try (Connection connection = createConnection()) {
       connection.setSavepointSupport(SavepointSupport.ENABLED);
       connection.setKeepTransactionAlive(true);
       // Start a transaction by executing a statement.
       connection.execute(INSERT_STATEMENT);
       // Verify that we get a keep-alive request.
-      verifyHasKeepAliveRequest();
+      verifyHasKeepAliveRequest(keepAliveTag);
       // Set a savepoint, execute another statement, and rollback to the savepoint.
       // The keep-alive should not be sent after the transaction has been rolled back to the
       // savepoint.
       connection.savepoint("s1");
       connection.execute(INSERT_STATEMENT);
       connection.rollbackToSavepoint("s1");
       mockSpanner.waitForRequestsToContain(RollbackRequest.class, 1000L);
-      // Wait for up to 2 milliseconds to make sure that any keep-alive requests that were in flight
-      // have finished.
-      try {
-        mockSpanner.waitForRequestsToContain(
-            r -> {
-              if (!(r instanceof ExecuteSqlRequest)) {
-                return false;
-              }
-              ExecuteSqlRequest request = (ExecuteSqlRequest) r;
-              return request.getSql().equals("SELECT 1")
-                  && request
-                      .getRequestOptions()
-                      .getRequestTag()
-                      .equals("connection.transaction-keep-alive");
-            },
-            2L);
-      } catch (TimeoutException ignore) {
-      }
+      String keepAliveTagAfterRollback = "test_keep_alive_tag_after_rollback";
+      System.setProperty("spanner.connection.keep_alive_query_tag", keepAliveTagAfterRollback);
 
-      // Verify that we don't get any keep-alive requests from this point.
-      mockSpanner.clearRequests();
+      // Verify that we don't get any new keep-alive requests from this point.
       Thread.sleep(2L);
-      assertEquals(0, countKeepAliveRequest());
+      assertEquals(0, countKeepAliveRequest(keepAliveTagAfterRollback));
       // Resume the transaction and verify that we get a keep-alive again.
       connection.execute(INSERT_STATEMENT);
-      verifyHasKeepAliveRequest();
+      verifyHasKeepAliveRequest(keepAliveTagAfterRollback);
     } finally {
       System.clearProperty("spanner.connection.keep_alive_interval_millis");
+      System.clearProperty("spanner.connection.keep_alive_query_tag");
     }
   }
 
-  private void verifyHasKeepAliveRequest() throws InterruptedException, TimeoutException {
+  private void verifyHasKeepAliveRequest(String tag) throws InterruptedException, TimeoutException {
     mockSpanner.waitForRequestsToContain(
         r -> {
           if (!(r instanceof ExecuteSqlRequest)) {
             return false;
           }
           ExecuteSqlRequest request = (ExecuteSqlRequest) r;
           return request.getSql().equals("SELECT 1")
-              && request
-                  .getRequestOptions()
-                  .getRequestTag()
-                  .equals("connection.transaction-keep-alive");
+              && request.getRequestOptions().getRequestTag().equals(tag);
         },
         1000L);
   }
 
-  private long countKeepAliveRequest() {
+  private long countKeepAliveRequest(String tag) {
     return mockSpanner.getRequestsOfType(ExecuteSqlRequest.class).stream()
         .filter(
             request ->
                 request.getSql().equals("SELECT 1")
-                    && request
-                        .getRequestOptions()
-                        .getRequestTag()
-                        .equals("connection.transaction-keep-alive"))
+                    && request.getRequestOptions().getRequestTag().equals(tag))
         .count();
   }
 }