Squashable commit; moved poor-man's integration test of JDBC Transact…

…ions where it belongs

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

transaction/jdbc/pom.xml

@@ -55,6 +55,16 @@
             <groupId>io.helidon.transaction</groupId>
             <artifactId>helidon-transaction</artifactId>
         </dependency>
+        <dependency>
+            <groupId>io.helidon.data.sql.datasource</groupId>
+            <artifactId>helidon-data-sql-datasource-hikari</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-api</artifactId>

transaction/jdbc/src/test/java/io/helidon/transaction/jdbc/TransactionalDataSourceTest.java

@@ -16,12 +16,18 @@
 package io.helidon.transaction.jdbc;
 
 import java.sql.Connection;
+import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.sql.Statement;
 
 import javax.sql.DataSource;
 
+import io.helidon.service.registry.Services;
+import io.helidon.transaction.Tx;
+
 import org.junit.jupiter.api.Test;
 
+import static io.helidon.transaction.Tx.Type.REQUIRED;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.sameInstance;
@@ -33,7 +39,7 @@ private TransactionalDataSourceTest() {
     }
 
     @Test
-    void getConnectionDelegatesToConnectionResolver() throws SQLException {
+    void testGetConnectionDelegatesToConnectionResolver() throws SQLException {
         Connection expectedConnection = new ConnectionStub();
         RecordingConnectionResolver connectionResolver = new RecordingConnectionResolver(expectedConnection);
         DataSource delegate = new DataSourceStub();
@@ -46,7 +52,7 @@ void getConnectionDelegatesToConnectionResolver() throws SQLException {
     }
 
     @Test
-    void credentialedGetConnectionDelegatesToConnectionResolver() throws SQLException {
+    void testGetConnectionWithUsernamePasswordUsesConnectionResolver() throws SQLException {
         Connection expectedConnection = new ConnectionStub();
         RecordingConnectionResolver connectionResolver = new RecordingConnectionResolver(expectedConnection);
         DataSource delegate = new DataSourceStub();
@@ -58,6 +64,31 @@ void credentialedGetConnectionDelegatesToConnectionResolver() throws SQLExceptio
         assertThat(connectionResolver.password(), is("tiger"));
     }
 
+    @Test
+    void testLightweightIntegrationScenario() throws SQLException {
+        DataSource ds = Services.get(DataSource.class);
+        Tx.transaction(REQUIRED, () -> {
+            try (Connection c = ds.getConnection();
+                 Statement statement = c.createStatement()) {
+                // autoCommit is false if we're "in" a transaction, i.e. helidon-transaction-jdbc is in effect
+                assertThat(c.getAutoCommit(), is(false));
+                statement.executeUpdate("CREATE TABLE IF NOT EXISTS EXAMPLE (ID INT PRIMARY KEY)");
+                statement.executeUpdate("INSERT INTO EXAMPLE (ID) VALUES (1)");
+            }
+            return null;
+            });
+
+        try (Connection c = ds.getConnection();
+             Statement statement = c.createStatement();
+             ResultSet rs = statement.executeQuery("SELECT COUNT(*) FROM EXAMPLE")) {
+            // autoCommit is true if we're *not* "in" a transaction
+            assertThat(c.getAutoCommit(), is(true));
+            assertThat(rs.next(), is(true));
+            assertThat(rs.getInt(1), is(1));
+            assertThat(rs.next(), is(false));
+        }
+    }
+
     private static final class RecordingConnectionResolver implements ConnectionResolver {
 
         private final Connection connection;