feat: allow unknown properties in connection url with lenient mode

src/main/java/com/google/cloud/spanner/jdbc/JdbcDriver.java

@@ -28,6 +28,7 @@
 import java.sql.DriverPropertyInfo;
 import java.sql.SQLException;
 import java.sql.SQLFeatureNotSupportedException;
+import java.sql.SQLWarning;
 import java.util.Map.Entry;
 import java.util.Properties;
 import java.util.logging.Logger;
@@ -172,7 +173,11 @@ public Connection connect(String url, Properties info) throws SQLException {
           // Connection API
           String connectionUri = appendPropertiesToUrl(url.substring(5), info);
           ConnectionOptions options = ConnectionOptions.newBuilder().setUri(connectionUri).build();
-          return new JdbcConnection(url, options);
+          JdbcConnection connection = new JdbcConnection(url, options);
+          if (options.getWarnings() != null) {
+            connection.pushWarning(new SQLWarning(options.getWarnings()));
+          }
+          return connection;
         }
       } catch (SpannerException e) {
         throw JdbcSqlExceptionFactory.of(e);

src/test/java/com/google/cloud/spanner/jdbc/JdbcDriverTest.java

@@ -161,4 +161,32 @@ public String apply(DriverPropertyInfo input) {
             });
     assertThat(driverPropertyNames).containsExactlyElementsIn(validConnectionPropertyNames);
   }
+
+  @Test
+  public void testLenient() throws SQLException {
+    // With lenient=true the driver should accept unknown properties and only generate a warning.
+    try (Connection connection =
+        DriverManager.getConnection(
+            String.format(
+                "jdbc:cloudspanner://localhost:%d/projects/p/instances/i/databases/d?usePlainText=true;lenient=true;foo=bar",
+                server.getPort()))) {
+      assertThat(connection.isClosed()).isFalse();
+      assertThat((Throwable) connection.getWarnings()).isNotNull();
+      assertThat(connection.getWarnings().getMessage()).contains("foo");
+    }
+
+    // Without lenient the driver should throw an exception for unknown properties.
+    try (Connection connection =
+        DriverManager.getConnection(
+            String.format(
+                "jdbc:cloudspanner://localhost:%d/projects/p/instances/i/databases/d?usePlainText=true;foo=bar",
+                server.getPort()))) {
+      fail("missing expected exception");
+    } catch (SQLException e) {
+      assertThat((Throwable) e).isInstanceOf(JdbcSqlException.class);
+      JdbcSqlException jdbc = (JdbcSqlException) e;
+      assertThat(jdbc.getMessage()).contains("foo");
+      assertThat(jdbc.getCode()).isEqualTo(Code.INVALID_ARGUMENT);
+    }
+  }
 }