From 3c9d7794af1005180321899093956b4a7141d063 Mon Sep 17 00:00:00 2001
From: Andrew Purtell <apurtell@apache.org>
Date: Fri, 1 May 2026 16:28:10 -0700
Subject: [PATCH] PHOENIX-7826 MetadataGetTableReadLockIT wait for coprocessor
 swap to land

---
 .../end2end/MetadataGetTableReadLockIT.java   | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/phoenix-core/src/it/java/org/apache/phoenix/end2end/MetadataGetTableReadLockIT.java b/phoenix-core/src/it/java/org/apache/phoenix/end2end/MetadataGetTableReadLockIT.java
index 392e74ddbe0..f2344fc8c93 100644
--- a/phoenix-core/src/it/java/org/apache/phoenix/end2end/MetadataGetTableReadLockIT.java
+++ b/phoenix-core/src/it/java/org/apache/phoenix/end2end/MetadataGetTableReadLockIT.java
@@ -23,6 +23,8 @@
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.CountDownLatch;
+import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.regionserver.HRegion;
 import org.apache.hadoop.hbase.regionserver.Region;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.phoenix.coprocessor.MetaDataEndpointImpl;
@@ -72,6 +74,7 @@ public void testBlockedReadDoesNotBlockAnotherRead() throws Exception {
       BlockingMetaDataEndpointImpl.setSleepSignal(sleepSignal);
       BlockingMetaDataEndpointImpl.setSleepDuration(SLEEP_DURATION);
       TestUtil.addCoprocessor(conn, "SYSTEM.CATALOG", BlockingMetaDataEndpointImpl.class);
+      waitForCoprocessorOnSystemCatalog(BlockingMetaDataEndpointImpl.class);
 
       // start thread-1 and wait for signal before it starts sleeping
       Thread t1 = getQueryThread(tableName);
@@ -94,6 +97,23 @@ public void testBlockedReadDoesNotBlockAnotherRead() throws Exception {
     }
   }
 
+  private static void waitForCoprocessorOnSystemCatalog(Class<?> coprocessorClass) throws Exception {
+    final TableName sysCatalog = TableName.valueOf("SYSTEM.CATALOG");
+    utility.waitFor(10000, 100, () -> {
+      List<HRegion> regions = utility.getHBaseCluster().getRegions(sysCatalog);
+      if (regions.isEmpty()) {
+        return false;
+      }
+      for (HRegion region : regions) {
+        if (region.getCoprocessorHost()
+            .findCoprocessor(coprocessorClass.getName()) == null) {
+          return false;
+        }
+      }
+      return true;
+    });
+  }
+
   private static Thread getQueryThread(String tableName) {
     Runnable runnable = () -> {
       try (Connection conn1 = DriverManager.getConnection(getUrl())) {