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How to chain 2 Uni<?> in unit test using Panache.withTransaction() without getting a java.util.concurrent.TimeoutException

I'm struggling using Panache.withTransaction() in unit tests, whatever I do, I get a java.util.concurrent.TimeoutException.
Note: It works without transaction but I have to delete the inserts manually.
I want to chain insertKline and getOhlcList inside a transaction so I can benefit from the rollback:
#QuarkusTest
#Slf4j
class KlineServiceTest {
#Inject
KlineRepository klineRepository;
#Inject
CurrencyPairRepository currencyPairRepository;
#Inject
KlineService service;
#Test
#DisplayName("ohlc matches inserted kline")
void ohlcMatchesInsertedKline() {
// GIVEN
val volume = BigDecimal.valueOf(1d);
val closeTime = LocalDateTime.now().withSecond(0).withNano(0);
val currencyPair = new CurrencyPair("BTC", "USDT");
val currencyPairEntity = currencyPairRepository
.findOrCreate(currencyPair)
.await().indefinitely();
val kline = KlineEntity.builder()
.id(new KlineId(currencyPairEntity, closeTime))
.volume(volume)
.build();
val insertKline = Uni.createFrom().item(kline)
.call(klineRepository::persistAndFlush);
val getOhlcList = service.listOhlcByCurrencyPairAndTimeWindow(currencyPair, ofMinutes(5));
// WHEN
val ohlcList = Panache.withTransaction(
() -> Panache.currentTransaction()
.invoke(Transaction::markForRollback)
.replaceWith(insertKline)
.chain(() -> getOhlcList))
.await().indefinitely();
// THEN
assertThat(ohlcList).hasSize(1);
val ohlc = ohlcList.get(0);
assertThat(ohlc).extracting(Ohlc::getCloseTime, Ohlc::getVolume)
.containsExactly(closeTime, volume);
}
}
I get this exception:
java.lang.RuntimeException: java.util.concurrent.TimeoutException
at io.quarkus.hibernate.reactive.panache.common.runtime.AbstractJpaOperations.executeInVertxEventLoop(AbstractJpaOperations.java:52)
at io.smallrye.mutiny.operators.uni.UniRunSubscribeOn.subscribe(UniRunSubscribeOn.java:25)
at io.smallrye.mutiny.operators.AbstractUni.subscribe(AbstractUni.java:36)
And looking at AbstractJpaOperations, I can see:
public abstract class AbstractJpaOperations<PanacheQueryType> {
// FIXME: make it configurable?
static final long TIMEOUT_MS = 5000;
...
}
Also, same issue when I tried to use runOnContext():
#Test
#DisplayName("ohlc matches inserted kline")
void ohlcMatchesInsertedKline() throws ExecutionException, InterruptedException {
// GIVEN
val volume = BigDecimal.valueOf(1d);
val closeTime = LocalDateTime.now().withSecond(0).withNano(0);
val currencyPair = new CurrencyPair("BTC", "USDT");
val currencyPairEntity = currencyPairRepository
.findOrCreate(currencyPair)
.await().indefinitely();
val kline = KlineEntity.builder()
.id(new KlineId(currencyPairEntity, closeTime))
.volume(volume)
.build();
val insertKline = Uni.createFrom().item(kline)
.call(klineRepository::persist);
val getOhlcList = service.listOhlcByCurrencyPairAndTimeWindow(currencyPair, ofMinutes(5));
val insertAndGet = insertKline.chain(() -> getOhlcList);
// WHEN
val ohlcList = runAndRollback(insertAndGet)
.runSubscriptionOn(action -> vertx.getOrCreateContext()
.runOnContext(action))
.await().indefinitely();
// THEN
assertThat(ohlcList).hasSize(1);
val ohlc = ohlcList.get(0);
assertThat(ohlc).extracting(Ohlc::getCloseTime, Ohlc::getVolume)
.containsExactly(closeTime, volume);
}
private static Uni<List<Ohlc>> runAndRollback(Uni<List<Ohlc>> getOhlcList) {
return Panache.withTransaction(
() -> Panache.currentTransaction()
.invoke(Transaction::markForRollback)
.replaceWith(getOhlcList));
}

Annotation #TestReactiveTransaction
Quarkus provides the annotation #TestReactiveTransaction: it will wrap the test method in a transaction and rollback the transaction at the end.
I'm going to use quarkus-test-vertx for testing the reactive code:
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-test-vertx</artifactId>
<scope>test</scope>
</dependency>
Here's an example of a test class that can be used with the Hibernate Reactive quickstart with Panache (after adding the quarkus-test-vertx dependency):
The entity:
#Entity
public class Fruit extends PanacheEntity {
#Column(length = 40, unique = true)
public String name;
...
}
The test class:
package org.acme.hibernate.orm.panache;
import java.util.List;
import org.junit.jupiter.api.Test;
import io.quarkus.test.TestReactiveTransaction;
import io.quarkus.test.junit.QuarkusTest;
import io.quarkus.test.vertx.UniAsserter;
import io.smallrye.mutiny.Uni;
import org.assertj.core.api.Assertions;
#QuarkusTest
public class ExampleReactiveTest {
#Test
#TestReactiveTransaction
public void test(UniAsserter asserter) {
printThread( "Start" );
Uni<List<Fruit>> listAllUni = Fruit.<Fruit>listAll();
Fruit mandarino = new Fruit( "Mandarino" );
asserter.assertThat(
() -> Fruit
.persist( mandarino )
.replaceWith( listAllUni ),
result -> {
Assertions.assertThat( result ).hasSize( 4 );
Assertions.assertThat( result ).contains( mandarino );
printThread( "End" );
}
);
}
private void printThread(String step) {
System.out.println( step + " - " + Thread.currentThread().getId() + ":" + Thread.currentThread().getName() );
}
}
#TestReactiveTransaction runs the method in a transaction that it's going to be rollbacked at the end of the test.
UniAsserter makes it possible to test reactive code without having to block anything.
Annotation #RunOnVertxContext
It's also possible to run a test in the Vert.x event loop using the annotation #RunOnVertxContext in the quarkus-vertx-test library:
This way you don't need to wrap the whole test in a trasaction:
import io.quarkus.test.vertx.RunOnVertxContext;
#QuarkusTest
public class ExampleReactiveTest {
#Test
#RunOnVertxContext
public void test(UniAsserter asserter) {
printThread( "Start" );
Uni<List<Fruit>> listAllUni = Fruit.<Fruit>listAll();
Fruit mandarino = new Fruit( "Mandarino" );
asserter.assertThat(
() -> Panache.withTransaction( () -> Panache
// This test doesn't have #TestReactiveTransaction
// we need to rollback the transaction manually
.currentTransaction().invoke( Mutiny.Transaction::markForRollback )
.call( () -> Fruit.persist( mandarino ) )
.replaceWith( listAllUni )
),
result -> {
Assertions.assertThat( result ).hasSize( 4 );
Assertions.assertThat( result ).contains( mandarino );
printThread( "End" );
}
);
}

I finally managed to get it working, the trick was to defer the Uni creation:
Like in:
#QuarkusTest
public class ExamplePanacheTest {
#Test
public void test() {
final var mandarino = new Fruit("Mandarino");
final var insertAndGet = Uni.createFrom()
.deferred(() -> Fruit.persist(mandarino)
.replaceWith(Fruit.<Fruit>listAll()));
final var fruits = runAndRollback(insertAndGet)
.await().indefinitely();
assertThat(fruits).hasSize(4)
.contains(mandarino);
}
private static Uni<List<Fruit>> runAndRollback(Uni<List<Fruit>> insertAndGet) {
return Panache.withTransaction(
() -> Panache.currentTransaction()
.invoke(Transaction::markForRollback)
.replaceWith(insertAndGet));
}
}

Vaadin: How do I display data from a MySQL database?

I'm developing a Vaadin Flow (version 14.1) app and I have this issue, I don't get it to connect directly with MySQL database.
I have set up the JDBC connection with maven, I've also created a singleton class I call Datasource where I store my values and methods. However right now it only has one as I'm testing this, this is what I want to do:
Click on a button on the app and update a label
Here's the button click listener:
button.addClickListener(click -> {
label.setText(Datasource.getInstance().getUsername());
});
Here's the Datasource class method:
public String getUsername() {
String username = "QUERY-FAILED";
try {
start();
statement = conn.createStatement();
ResultSet rs = statement.executeQuery("select * from names");
rs.next();
username = rs.getString(1);
} catch (SQLException e) {
e.printStackTrace();
} finally {
close();
}
return username;
}
But the label doesn't update, if I comment the try block it updates to QUERY-FAILED which is the string I put to test if it failed, but if it isn't commented the label just stays the same.
I also tried to add a main method to the Datasource class and run it as a Java application, and the method works fine, it does return a string with the username. So I'm guessing I'm stuck somewhere in between the connection with the vaadin app. Also, If I try to get the username String in my vaadin app when I'm starting the app (and not with a click listener) I got an long stack of errors with the Datasource indicating a nullpointerexception here:
statement = conn.createStatement();
Thanks in advance!

I cannot spot any problem with your code. But I can provide an entire working example app for you to compare
My example app goes along the lines laid out in your Question's code. A Vaadin Button performs a database query using a DataSource object from a table of user names. The value from the first row found is displayed in a Vaadin Label widget on the web page.
This app was built and run with Vaadin 14.1.5 using a "Plain Java Servlet" flavor of a starter project provided by the Vaadin.com site. Running on macOS Mojave with the bundled Jetty web container.
My only changes to their Maven POM file was to change to Java version 13, and to add a dependency for H2 Database Engine to make this a self-contained example using an in-memory database.
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<version>1.4.200</version>
</dependency>
I used the hook for Vaadin starting, to establish my DataSource object and initialize the database. Following the manual, nested in the resources folder, I created folders META-INF > services. Per the Java SPI facility, there I created a file named com.vaadin.flow.server.VaadinServiceInitListener containing a single line to specify the name of my class that implements the interface named in the name of this file:
work.basil.example.ApplicationServiceInitListener
That is, my ApplicationServiceInitListener class implement the Vaadin interface VaadinServiceInitListener. My class will be automatically instantiated and its method invoked via that Java SPI facility when my Vaadin web app launches.
My ApplicationServiceInitListener class:
package work.basil.example;
import com.vaadin.flow.server.ServiceInitEvent;
import com.vaadin.flow.server.VaadinServiceInitListener;
import org.h2.jdbcx.JdbcDataSource;
public class ApplicationServiceInitListener implements VaadinServiceInitListener
{
#Override
public void serviceInit ( ServiceInitEvent serviceInitEvent )
{
System.out.println( "DEBUG Running `serviceInit` of " + this.getClass().getCanonicalName() );
// Database work.
prepareDataSource();
App.INSTANCE.provideDatabase().initializeDatabase();
}
private void prepareDataSource ( )
{
JdbcDataSource ds = new JdbcDataSource();
ds.setURL( "jdbc:h2:mem:demo;DB_CLOSE_DELAY=-1" );
ds.setUser( "scott" );
ds.setPassword( "tiger" );
App.INSTANCE.rememberDataSource( ds );
}
}
That class calls my App class which acts as a sort of service locator. Designed as a singleton via enum.
package work.basil.example;
import javax.sql.DataSource;
import java.util.Objects;
public enum App
{
INSTANCE;
// -------| DataSource |---------------------------------
private DataSource dataSource;
public DataSource provideDataSource ( )
{
return this.dataSource;
}
public void rememberDataSource ( DataSource dataSource )
{
this.dataSource = Objects.requireNonNull( dataSource );
}
// -------| Database |---------------------------------
private Database database;
public Database provideDatabase ( )
{
return new Database();
}
}
That class calls my Database class. In real work, Database would be an interface with various concrete implementations for testing versus deployment. I ignored that here for demonstration purposes.
package work.basil.example;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Database
{
public String getFirstUserName ( )
{
String userName = "QUERY-FAILED";
String newline = "\n";
StringBuilder sql = new StringBuilder();
sql.append( "SELECT name_ from user_ ; " ).append( newline );
System.out.println( "sql = " + sql );
try (
Connection conn = App.INSTANCE.provideDataSource().getConnection() ;
Statement statement = conn.createStatement() ;
ResultSet resultSet = statement.executeQuery( sql.toString() ) ;
)
{
while ( resultSet.next() )
{
userName = resultSet.getString( "name_" );
break; // Go no further. We need only the first row found.
}
}
catch ( SQLException e )
{
e.printStackTrace();
}
return userName;
}
public void initializeDatabase ( )
{
System.out.println( "DEBUG Running `initializeDatabase` of " + this.getClass().getCanonicalName() );
String newline = "\n";
// Create table.
StringBuilder sql = new StringBuilder();
sql.append( "CREATE TABLE user_ ( " ).append( newline );
sql.append( "pkey_ IDENTITY NOT NULL PRIMARY KEY , " ).append( newline ); // `identity` = auto-incrementing long integer.
sql.append( "name_ VARCHAR NOT NULL " ).append( newline );
sql.append( ") " ).append( newline );
sql.append( ";" ).append( newline );
System.out.println( "sql = " + sql );
try (
Connection conn = App.INSTANCE.provideDataSource().getConnection() ;
Statement statement = conn.createStatement() ;
)
{
statement.executeUpdate( sql.toString() );
}
catch ( SQLException e )
{
e.printStackTrace();
}
System.out.println("DEBUG Finished `CREATE TABLE` statement.");
// Populate table.
sql = new StringBuilder();
sql.append( "INSERT INTO user_ ( name_ ) " ).append( newline );
sql.append( "VALUES " ).append( newline );
sql.append( "( 'Alice' ) , " ).append( newline );
sql.append( "( 'Bob' ) , " ).append( newline );
sql.append( "( 'Carol' ) " ).append( newline );
sql.append( ";" ).append( newline );
System.out.println( "sql = " + sql );
try (
Connection conn = App.INSTANCE.provideDataSource().getConnection() ;
Statement statement = conn.createStatement() ;
)
{
int rowsAffected = statement.executeUpdate( sql.toString() );
System.out.println( "DEBUG Inserted rows into name_ table: " + rowsAffected );
}
catch ( SQLException e )
{
e.printStackTrace();
}
System.out.println("DEBUG Finished `INSERT` statement.");
}
}
And lastly, the MainView class. I disable the #PWA annotation as we are not using that feature for progressive web apps.
package work.basil.example;
import com.vaadin.flow.component.button.Button;
import com.vaadin.flow.component.html.Label;
import com.vaadin.flow.component.notification.Notification;
import com.vaadin.flow.component.orderedlayout.VerticalLayout;
import com.vaadin.flow.router.Route;
/**
* The main view contains a button and a click listener.
*/
#Route ( "" )
//#PWA ( name = "Project Base for Vaadin", shortName = "Project Base" )
public class MainView extends VerticalLayout
{
private Label label;
private Button button;
public MainView ( )
{
// Widgets
this.label = new Label( "User: ?" );
this.button = new Button(
"Get user" ,
event -> {
Notification.show( "Getting user." );
String userName = App.INSTANCE.provideDatabase().getFirstUserName();
this.label.setText( "User: " + userName );
}
);
add( button );
// Arrange
this.add( label , button );
}
}

You should check if the ResultSet rs actually has results. When calling rs.next(), look if it returns false. How to check if ResultSet is empty
public String getUsername() {
String username = "QUERY-FAILED";
try {
start();
statement = conn.createStatement();
ResultSet rs = statement.executeQuery("select userName from names");
if(rs.next() != false){
username = rs.getString(1);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
close();
}
return username;
}
Another thing I noticed is that from the query select * from names, one cannot be sure that the userName attribute is the first column, which you are reading with rs.getString(1). Make sure to write your query more precise to avoid hard-to-find bugs: select userName from names; Do this even if the table only has one column, because what if somebody prepended another column? it could break your application.

Neo4j - java Authentication failure

I'm a beginner for Java and neo4j.
Trying my first connection to neo4j using Java Application. I'm unable to understand why I am getting Error:
Exception in thread "main" org.neo4j.driver.v1.exceptions.AuthenticationException: The client is unauthorized due to authentication failure.
Bolt : bolt://localhost:7687 (neo4j Desktop on my macbook)
GraphName : PrakashTest1
Password : 12345678
Java Application:
import org.neo4j.driver.v1.AuthTokens;
import org.neo4j.driver.v1.Driver;
import org.neo4j.driver.v1.GraphDatabase;
import org.neo4j.driver.v1.Session;
import org.neo4j.driver.v1.StatementResult;
import org.neo4j.driver.v1.Transaction;
import org.neo4j.driver.v1.TransactionWork;
import static org.neo4j.driver.v1.Values.parameters;
public class HelloWorldExample implements AutoCloseable {
private final Driver driver;
public HelloWorldExample( String uri, String user, String password )
{
driver = GraphDatabase.driver( uri, AuthTokens.basic( user, password ) );
}
#Override
public void close() throws Exception
{
driver.close();
}
public void printGreeting( final String message ) {
try ( Session session = driver.session() )
{
String greeting = session.writeTransaction( new TransactionWork<String>()
{
#Override
public String execute( Transaction tx )
{
StatementResult result = tx.run( "CREATE (a:Greeting) " +
"SET a.message = $message " +
"RETURN a.message + ', from node ' + id(a)",
parameters( "message", message ) );
return result.single().get( 0 ).asString();
}
} );
System.out.println( greeting );
}
}
public static void main( String... args ) throws Exception
{
try ( HelloWorldExample greeter = new HelloWorldExample( "bolt://localhost:7687", "PrakashTest1", "12345678" ) )
{
greeter.printGreeting( "hello, world" );
}
}
}

How to run dql search query in java?

I want to check whether a file is present in a particular folder in documentum using Java.
Following is my code,
import com.documentum.com.DfClientX;
import com.documentum.com.IDfClientX;
import com.documentum.fc.client.DfQuery;
import com.documentum.fc.client.IDfClient;
import com.documentum.fc.client.IDfCollection;
import com.documentum.fc.client.IDfFolder;
import com.documentum.fc.client.IDfQuery;
import com.documentum.fc.client.IDfSession;
import com.documentum.fc.client.IDfSessionManager;
import com.documentum.fc.common.DfException;
import com.documentum.fc.common.DfId;
import com.documentum.fc.common.IDfLoginInfo;
import com.documentum.operations.IDfDeleteOperation;
public class CountFiles {
// Documentum target repository where the files will be imported
private static final String REPO_NAME = "rep";
public static void main( String[] args ) throws Exception {
try {
String username = "user";
String password = "pwd";
System.out.println( "Starting to connect ..." );
IDfSessionManager sessMgr = createSessionManager( );
addIdentity( sessMgr, username, password);
IDfSession sess = sessMgr.getSession(REPO_NAME );
System.out.println( "Successfully connected to the server.");
queryDocumentum(sess);
} catch( Exception ex ) {
System.out.println( ex );
ex.printStackTrace( );
}
}
private static void queryDocumentum(IDfSession sess) throws DfException {
IDfQuery query = new DfQuery();
String queryStr= "select count(*) from dm_document WHERE FOLDER ('/XXX/YYY',DESCEND) search document contains 'abc.pdf' ";
query.setDQL(queryStr);
IDfCollection coll = query.execute(sess,IDfQuery.DF_EXEC_QUERY);
while(coll.next())
{
System.out.println("Result of method: " + coll.getValueAt(0));
}
coll.close();
}
/**
* Creates a new session manager instance. The session manager does not have
* any identities associated with it.
*
* #return a new session manager object.
* #throws DfException
*/
private static IDfSessionManager createSessionManager( )
throws Exception {
IDfClientX clientX = new DfClientX( );
IDfClient localClient = clientX.getLocalClient( );
IDfSessionManager sessMgr = localClient.newSessionManager( );
System.out.println( "Created session manager." );
return sessMgr;
}
/**
* Adds a new identity to the session manager.
*
*/
private static void addIdentity( final IDfSessionManager sm,
final String username, final String password )
throws Exception {
IDfClientX clientX = new DfClientX( );
IDfLoginInfo li = clientX.getLoginInfo( );
li.setUser( username );
li.setPassword( password );
// check if session manager already has an identity.
// if yes, remove it.
if( sm.hasIdentity( REPO_NAME ) ) {
sm.clearIdentity( REPO_NAME );
System.out.println( "Cleared identity on :" + REPO_NAME );
}
sm.setIdentity( REPO_NAME, li );
System.out.println( "Set up identity for the user." );
}
}
I am getting the following exception - [DM_QUERY_E_SYNTAX]error: "A Parser Error (syntax error) has occurred in the vicinity of "select count(*) from dm_document WHERE FOLDER ('/XXX/YYY',DESCEND) search document contains 'abc.pdf'". what is the issue in the query/code?

Well, obviously your DQL query is wrong:
select count(*) from dm_document WHERE FOLDER ('/XXX/YYY',DESCEND) search document contains 'abc.pdf'
if you just want to check if some document named 'abc.pdf' is present in path /XXX/YYY and all folders below (keyword 'descend') then the DQL should be more like this, you don't need Full Text search capabilities for that:
select count(*) from dm_document where folder('/XXX/YYY', DESCEND) and object_name = 'abc.pdf'
If you don't know exact file name you can use "LIKE", for example:
select count(*) from dm_document where folder('/XXX/YYY', DESCEND) and object_name LIKE '%abc.pdf'

Neo4j embedded only stores inside one runtime

I'm experimenting with Neo4J via Embedded Java API.
My Build path seems ok (no Exceptions during runtime).
When I create some nodes and relations, I can query it directly after it with success.
But after shutting down and re-run my programm, i'm only getting the data I created in the new runtime and none of them before.
But if I look at my directory, I see, that the size has grown with each runtime, I perform a creating of data.
Here's my code:
public static void main(String[] args)
{
GraphDatabaseService gdb = new GraphDatabaseFactory().newEmbeddedDatabase( "/mytestdb/" );
create( gdb );
query( gdb );
gdb.shutdown();
}
private static void query( GraphDatabaseService gdb )
{
StringLogger sl = StringLogger.wrap( new Writer()
{
#Override
public void write( char[] arg0, int arg1, int arg2 ) throws IOException
{
for( int i=arg1; i<=arg2; i++ ) System.out.print( arg0[i] );
}
#Override
public void flush() throws IOException
{}
#Override
public void close() throws IOException
{}
} );
ExecutionEngine ee = new ExecutionEngine( gdb, sl );
ExecutionResult result = ee.execute( "MATCH (p:Privilleg) RETURN p" );
System.out.println( result.dumpToString() );
}
private static void create( GraphDatabaseService gdb )
{
Transaction tx = gdb.beginTx();
Node project = gdb.createNode( MyLabels.Project );
Node user = gdb.createNode( MyLabels.User );
Node priv1 = gdb.createNode( MyLabels.Privilleg );
Node priv2 = gdb.createNode( MyLabels.Privilleg );
user.setProperty( "name", "Heinz" );
user.setProperty( "email", "heinz#gmx.net" );
priv1.setProperty( "name", "Allowed to read all" );
priv1.setProperty( "targets", Short.MAX_VALUE );
priv1.setProperty( "read", true );
priv1.setProperty( "write", false );
priv2.setProperty( "name", "Allowed to write all" );
priv2.setProperty( "targets", Short.MAX_VALUE );
priv2.setProperty( "read", false );
priv2.setProperty( "write", true );
project.setProperty( "name", "My first project" );
project.setProperty( "sname", "STARTUP" );
user.createRelationshipTo( priv1, MyRelationships.UserPrivilleg );
user.createRelationshipTo( priv2, MyRelationships.UserPrivilleg );
priv1.createRelationshipTo( project, MyRelationships.ProjectPrivilleg );
priv2.createRelationshipTo( project, MyRelationships.ProjectPrivilleg );
tx.success();
}

Your code doesn't close the transaction. Typically you use a try-with-resources block:
try (Transaction tx=gdb.beginTx()) {
// do stuff in the graph
tx.success();
}
Since Transaction is AutoClosable its close() method will be called implicitly upon leaving the code block. If (for whatever) reason you decide not to use try-with-resources, be sure to explicitly call close().
On a different notice: your code uses ExecutionEngine. Since Neo4j 2.2 you directly call gdb.execute(myCypherString) instead.

Thank you! This works.
Also, before I closed the transaction, it takes about 20 seconds to shuting down the db. This also is now less than a second.