4.x: Installs a convenient default for connectionPoolName in UCPBacke…

…dDataSourceExtension when appropriate (helidon-io#8359)

* Installs a convenient default for connectionPoolName in UCPBackedDataSourceExtension when appropriate

Signed-off-by: Laird Nelson <laird.nelson@oracle.com>

* Squashable commit; diagnosing test failure that occurs only in the pipeline

Signed-off-by: Laird Nelson <laird.nelson@oracle.com>

* Squashable commit; destroys static connection pools after every test

Signed-off-by: Laird Nelson <laird.nelson@oracle.com>

---------

Signed-off-by: Laird Nelson <laird.nelson@oracle.com>

integrations/cdi/datasource-ucp/src/main/java/io/helidon/integrations/datasource/ucp/cdi/UCPBackedDataSourceExtension.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2023 Oracle and/or its affiliates.
+ * Copyright (c) 2019, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -234,6 +234,9 @@ private static PoolDataSource createDataSource(Instance<Object> instance,
                 }
             }
         }
+        if (returnValue.getConnectionPoolName() == null) {
+          returnValue.setConnectionPoolName(dataSourceName.value());
+        }
         Instance<SSLContext> sslContextInstance = instance.select(SSLContext.class, dataSourceName);
         if (!sslContextInstance.isUnsatisfied()) {
             returnValue.setSSLContext(sslContextInstance.get());

integrations/cdi/datasource-ucp/src/test/java/io/helidon/integrations/datasource/ucp/cdi/TestDataSourceAcquisition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2023 Oracle and/or its affiliates.
+ * Copyright (c) 2019, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -84,6 +84,7 @@ private void onStartup(@Observes @Initialized(ApplicationScoped.class) final Obj
         final PoolDataSourceImpl contextualInstance =
             (PoolDataSourceImpl) ((WeldClientProxy) this.test).getMetadata().getContextualInstance();
         assertThat(contextualInstance.getDescription(), is("A test datasource"));
+        assertThat(contextualInstance.getConnectionPoolName(), is("test"));
         Connection connection = null;
         try {
             connection = this.test.getConnection();

integrations/cdi/datasource-ucp/src/test/java/io/helidon/integrations/datasource/ucp/cdi/TestUcpApi.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2024 Oracle and/or its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.helidon.integrations.datasource.ucp.cdi;
+
+import java.sql.SQLException;
+import java.util.Properties;
+
+import oracle.ucp.UniversalConnectionPool;
+import oracle.ucp.UniversalConnectionPoolAdapter;
+import oracle.ucp.UniversalConnectionPoolException;
+import oracle.ucp.admin.UniversalConnectionPoolManager;
+import oracle.ucp.admin.UniversalConnectionPoolManagerImpl;
+import oracle.ucp.jdbc.PoolDataSource;
+import oracle.ucp.jdbc.PoolDataSourceFactory;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
+
+import static oracle.ucp.jdbc.PoolDataSourceFactory.getPoolDataSource;
+import static org.hamcrest.CoreMatchers.nullValue;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class TestUcpApi {
+
+    TestUcpApi() {
+        super();
+    }
+
+    @AfterEach
+    void destroyPools() throws SQLException, UniversalConnectionPoolException {
+        UniversalConnectionPoolManager ucpManager = UniversalConnectionPoolManagerImpl.getUniversalConnectionPoolManager();
+        for (String n : ucpManager.getConnectionPoolNames()) {
+            ucpManager.destroyConnectionPool(n);
+        }
+    }
+
+    @Test
+    void testGetPoolDataSourceWithName() throws SQLException {
+        // Some magic undocumented XML configuration file has not been set as a system property (!), so this call fails
+        // in an undocumented way.
+        assertThrows(SQLException.class, () -> getPoolDataSource("bogus"));
+    }
+
+    @Test
+    void testGetPoolDataSourceWithMinimalProperties() throws SQLException {
+        Properties p = new Properties();
+        p.setProperty("connectionPoolName", "bogusConnectionPoolName");
+        p.setProperty("dataSourceName", "bogusDataSourceName");
+        // This call fails without some XML file present somewhere (!).
+        assertThrows(SQLException.class, () -> getPoolDataSource(p));
+    }
+
+    @Test
+    void testDefaultConnectionPoolNameIsNull() throws SQLException, UniversalConnectionPoolException {
+        assertThat(getPoolDataSource().getConnectionPoolName(), is(nullValue()));
+    }
+
+    @Test
+    void testCreateConnectionPoolFailsWithoutSufficientInformation() throws SQLException, UniversalConnectionPoolException {
+        UniversalConnectionPoolManager ucpManager = UniversalConnectionPoolManagerImpl.getUniversalConnectionPoolManager();
+        assertThrows(UniversalConnectionPoolException.class,
+                     () -> ucpManager.createConnectionPool((UniversalConnectionPoolAdapter) getPoolDataSource()));
+    }
+
+    @Test
+    void testCreateConnectionPoolManuallyWithoutName() throws SQLException, UniversalConnectionPoolException {
+        PoolDataSource pds = getPoolDataSource();
+        pds.setConnectionFactoryClassName("org.h2.jdbcx.JdbcDataSource");
+        pds.setURL("jdbc:h2:mem:test");
+        assertThat(pds.getConnectionPoolName(), is(nullValue()));
+        assertThat(pds.getDataSourceName(), is(nullValue()));
+        UniversalConnectionPoolManager ucpManager = UniversalConnectionPoolManagerImpl.getUniversalConnectionPoolManager();
+        // You can create the pool without a name...
+        ucpManager.createConnectionPool((UniversalConnectionPoolAdapter)pds);
+        String[] names = ucpManager.getConnectionPoolNames();
+        assertThat("Connection pool names: " + java.util.Arrays.asList(names), names.length, is(1));
+        assertThat(names[0], is(not(nullValue())));
+        // ...and the name will be auto-generated.
+        UniversalConnectionPool ucp = ucpManager.getConnectionPool(names[0]);
+        assertThat(ucp.getName(), is(names[0]));
+        // This whole API is perhaps surprising: for example, here the creation of the pool modifies the pds that was
+        // serving as its creation template (!).
+        assertThat(pds.getConnectionPoolName(), is(names[0]));
+        // The dataSourceName appears never to be used or modified and may, perhaps, make sense only when the
+        // aforementioned XML file exists.
+        assertThat(pds.getDataSourceName(), is(nullValue()));
+    }
+
+}