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Creating TextIndex in Micronaut with reactive mongoDB

I am using reactive mongoDB with Micronaut application
implementation("io.micronaut.mongodb:micronaut-mongo-reactive")
Trying to create a TextIndex and search Free text functionality
public class Product {
#BsonProperty("id")
private ObjectId id;
private String name;
private float price;
private String description;
}
In spring data we have #TextIndexed(weight = 2) to create a TextIndex to the collection, what is the equivalent in the Micronaut application.

I'm afraid that Micronaut Data does not yet support automatic index creation based on annotations for MongoDB. Micronaut Data now simplifies only work with SQL databases.
But you can still create the index manually using MongoClient like this:
#Singleton
public class ProductRepository {
private final MongoClient mongoClient;
public ProductRepository(MongoClient mongoClient) {
this.mongoClient = mongoClient;
}
public MongoCollection<Product> getCollection() {
return mongoClient
.getDatabase("some-database")
.getCollection("product", Product.class);
}
#PostConstruct
public void createIndex() {
final var weights = new BasicDBObject("name", 10)
.append("description", 5);
getCollection()
.createIndex(
Indexes.compoundIndex(
Indexes.text("name"),
Indexes.text("description")
),
new IndexOptions().weights(weights)
)
.subscribe(new DefaultSubscriber<>() {
#Override
public void onNext(String s) {
System.out.format("Index %s was created.%n", s);
}
#Override
public void onError(Throwable t) {
t.printStackTrace();
}
#Override
public void onComplete() {
System.out.println("Completed");
}
});
}
}
You can of course use any subscriber you want. That anonymous class extending DefaultSubscriber is used here only for demonstration purpose.
Update: You can create indexes on startup for example by using #PostConstruct. It means to add all index creation logic in a method annotated by #PostConstruct in some repository or service class annotated by #Singleton, then it will be called after repository/service singleton creation.

Can prepared statements be enabled out of the box?

I would like to make use of prepared statements when executing CQL in my application. This functionality looks to be provided by the ReactiveCqlTemplate class, which I have passed into the ReactiveCassandraTemplate in my Cassandra configuration here:
#Configuration
#EnableReactiveCassandraRepositories(
basePackages = "com.my.app",
includeFilters = {
#ComponentScan.Filter(type = FilterType.ASSIGNABLE_TYPE, classes = {ScyllaPersonRepository.class})
})
public class CassandraConfiguration extends AbstractReactiveCassandraConfiguration {
#Value("${cassandra.host}")
private String cassandraHost;
#Value("${cassandra.connections}")
private Integer cassandraConnections;
#Override
public CassandraClusterFactoryBean cluster() {
PoolingOptions poolingOptions = new PoolingOptions()
.setCoreConnectionsPerHost(HostDistance.LOCAL, cassandraConnections)
.setMaxConnectionsPerHost(HostDistance.LOCAL, cassandraConnections*2);
CassandraClusterFactoryBean bean = super.cluster();
bean.setJmxReportingEnabled(false);
bean.setPoolingOptions(poolingOptions);
bean.setLoadBalancingPolicy(new TokenAwarePolicy(new RoundRobinPolicy()));
return bean;
}
#Override
public ReactiveCassandraTemplate reactiveCassandraTemplate() {
return new ReactiveCassandraTemplate(reactiveCqlTemplate(), cassandraConverter());
}
#Bean
public CassandraEntityInformation getCassandraEntityInformation(CassandraOperations cassandraTemplate) {
CassandraPersistentEntity<Person> entity =
(CassandraPersistentEntity<Person>)
cassandraTemplate
.getConverter()
.getMappingContext()
.getRequiredPersistentEntity(Person.class);
return new MappingCassandraEntityInformation<>(entity, cassandraTemplate.getConverter());
}
#Override
public SchemaAction getSchemaAction() {
return SchemaAction.CREATE_IF_NOT_EXISTS;
}
public String getContactPoints() {
return cassandraHost;
}
public String getKeyspaceName() {
return "mykeyspace";
}
}
This is the ScyllaPersonRepository referenced in my Cassandra configuration filters.
public interface ScyllaPersonRepository extends ReactiveCassandraRepository<Person, PersonKey> {
#Query("select id, name from persons where id = ?0")
Flux<Object> findPersonById(#Param("id") String id);
}
After executing a few queries, the CQL Non-Prepared statements metric in my Scylla Monitoring Dashboard showed that I'm not using prepared statements at all.
I was able to use prepared statements after followed the documentation here which walked me through creating the CQL myself.
public class ScyllaPersonRepository extends SimpleReactiveCassandraRepository<Person, PersonKey> {
private final Session session;
private final CassandraEntityInformation<Person, PersonKey> entityInformation;
private final ReactiveCassandraTemplate cassandraTemplate;
private final PreparedStatementCache cache = PreparedStatementCache.create();
public ScyllaPersonRepository(
Session session,
CassandraEntityInformation<Person, PersonKey> entityInformation,
ReactiveCassandraTemplate cassandraTemplate
) {
super(entityInformation, cassandraTemplate);
this.session = session;
this.entityInformation = entityInformation;
this.cassandraTemplate = cassandraTemplate;
}
public Flux<ScyllaUser> findSegmentsById(String id) {
return cassandraTemplate
.getReactiveCqlOperations()
.query(
findPersonByIdQuery(id),
(row, rowNum) -> convert(row)
);
}
private BoundStatement findPersonByIdQuery(String id) {
return CachedPreparedStatementCreator.of(
cache,
QueryBuilder.select()
.column("id")
.column("name")
.from("persons")
.where(QueryBuilder.eq("id", QueryBuilder.bindMarker("id"))))
.createPreparedStatement(session)
.bind()
.setString("id", id);
}
private Person convert(Row row) {
return new Person(
row.getString("id"),
row.getString("name"));
}
}
But, I would really like the ORM to handle that all for me. Is it possible to configure this behaviour out of the box, so that I don't need to manually write the CQL myself but instead just enable it as an option in my Cassandra Configuration and get the ORM to orchestrate it all behind the scenes?

Frankly, I think this is a bug(request for enhancement) and it should be filed in Springs Jira.
It seems the repository simply doesn't support this out of box(nor did I find any config option how to flip it, but I might have missed it).
Actually, my theory was correct:
https://jira.spring.io/projects/DATACASS/issues/DATACASS-578?filter=allopenissues
so just add yourself and try to ask them for resolution.

Use Dropwizard configuration in a method that establishes a connection to a MongoDB database

I am coding Dropwizard micro-services that fetch data in a MongoDB database. The micro-services work fine but I'm struggling to use in my DAO the configuration coming from my Dropwizard configuration Java class. Currently I have
public class XDAO implements IXDAO {
protected DB db;
protected DBCollection collection;
/* singleton */
private static XDAO instance;
/* Get singleton */
public static synchronized XDAO getSingleton(){
if (instance == null){
instance = new XDAO();
}
return instance;
}
/* constructor */
public XDAO(){
initDatabase();
initDatabaseIndexes();
}
private void initDatabase(){
MongoClient client = null;
try {
client = new Mongo("10.126.80.192",27017);
db = client.getDB("terre");
//then some other code
}
catch (final MongoException e){
...
}
catch (UnknownHostException e){
...
}
}
}
I want to unhard-code the three arguments in these two lines :
client = new Mongo("10.126.80.192", 27017);
db = client.getDB("terre");
My MongoConfiguration Java class is :
public class MongoConfiguration extends Configuration {
#JsonProperty
#NotEmpty
public String host;
#JsonProperty
public int port = 27017;
#JsonProperty
#NotEmpty
public String db_name;
public String getMongohost() {
return host;
}
public void setMongohost(String host) {
this.host = host;
}
public int getMongoport() {
return port;
}
public void setMongoport(int port) {
this.port = port;
}
public String getDb_name() {
return db_name;
}
public void setDb_name(String db_name) {
this.db_name = db_name;
}
}
My Resource class that uses the DAO is :
#Path("/mongo")
#Produces(MediaType.APPLICATION_JSON)
public class MyResource {
private XDAO xDAO = XDAO.getSingleton();
private String mongohost;
private String db_name;
private int mongoport;
public MyResource(String db_name, String mongohost, int mongoport) {
this.db_name = db_name;
this.mongohost = mongohost;
this.mongoport = mongoport;
}
public MyResource() {
}
#GET
#Path("/findByUUID")
#Produces(value = MediaType.APPLICATION_JSON)
#Timed
public Entity findByUUID(#QueryParam("uuid") String uuid) {
return xDAO.findByUUid(uuid);
}
}
And in my application class there is
#Override
public void run(final MongoConfiguration configuration, final Environment environment) {
final MyResource resource = new MyResource(configuration.getDb_name(), configuration.getMongohost(), configuration.getMongoport());
environment.jersey().register(resource);
}
To solve my problem I tried many things. The last thing I tried was to add these four fields in my XDAO
private String mongohost;
private String db_name;
private int mongoport;
private static final MongoConfiguration configuration = new MongoConfiguration();
Coming with this piece of code in the constructor of the XDAO:
public XDAO(){
instance.mongohost = configuration.getMongohost();
instance.mongoport = configuration.getMongoport();
instance.db_name = configuration.getDb_name();
/* then like before */
initDatabase();
initDatabaseIndexes();
}
When I try this I have a null pointer exception when my initDatabase method is invoked : mongoHost and db_name are null

The problem is that you are creating a new configuration in your XDAO with private static final MongoConfiguration configuration = new MongoConfiguration(); instead of using the config from Dropwizard's run method.
When you do this, the fields host and db_name in the new configuration are null, which is why you are getting the NPE when instantiating XDAO
You need to pass the instance of MongoConfiguration that you get from Dropwizard in your application class to your XDAO, ideally when the singleton XDAO is created so it has non-null values for db_name and host
This code below part of the problem - you are creating the singleton without giving XDAO the MongoConfiguration configuration instance.
public class XDAO implements IXDAO {
//... snip
/* Get singleton */
public static synchronized XDAO getSingleton(){
if (instance == null){
instance = new XDAO(); // no configuration information is included!
}
return instance;
}
/* constructor */
public XDAO(){
initDatabase(); // this call needs db_name & host but you haven't set those yet!!
initDatabaseIndexes();
}
I recommend you modify your application class to create XDAO along the lines of this:
#Override
public void run(final MongoConfiguration configuration, final Environment environment) {
XDAO XDAOsingleton = new XDAO(configuration);
XDAO.setSingletonInstance(XDAOsingleton); // You need to create this static method.
final MyResource resource = new MyResource(configuration.getDb_name(), configuration.getMongohost(), configuration.getMongoport()); // MyResource depends on XDAO so must be created after XAO's singleton is set
environment.jersey().register(resource);
}
You may also need to take initDatabase() etc out of XDAO's constructor depending on if you keep public static synchronized XDAO getSingleton()
I also recommend you change the constructor of MyResource to public MyResource(XDAO xdao). The resource class doesn't appear to need the configuration information, and it is better to make the dependency on an XDAO explicit (you then also don't need to keep the XDAO singleton in a static field inside XDAO's class).

To get MongoDB integrated in a simple way to Dropwizard, please try and use MongoDB Managed Object. I will explain this in 3 simple steps:
Step 1: Create a simple MongoManged class:
import com.mongodb.Mongo;
import io.dropwizard.lifecycle.Managed;
public class MongoManaged implements Managed {
private Mongo mongo;
public MongoManaged(Mongo mongo) {
this.mongo = mongo;
}
#Override
public void start() throws Exception {
}
#Override
public void stop() throws Exception {
mongo.close();
}
}
Step 2: Mention MongoDB Host, Port, DB Name in a config yml file:
mongoHost : localhost
mongoPort : 27017
mongoDB : softwaredevelopercentral
Step 3: Bind everything together in the Application Class:
public class DropwizardMongoDBApplication extends Application<DropwizardMongoDBConfiguration> {
private static final Logger logger = LoggerFactory.getLogger(DropwizardMongoDBApplication.class);
public static void main(String[] args) throws Exception {
new DropwizardMongoDBApplication().run("server", args[0]);
}
#Override
public void initialize(Bootstrap<DropwizardMongoDBConfiguration> b) {
}
#Override
public void run(DropwizardMongoDBConfiguration config, Environment env)
throws Exception {
MongoClient mongoClient = new MongoClient(config.getMongoHost(), config.getMongoPort());
MongoManaged mongoManaged = new MongoManaged(mongoClient);
env.lifecycle().manage(mongoManaged);
MongoDatabase db = mongoClient.getDatabase(config.getMongoDB());
MongoCollection<Document> collection = db.getCollection(config.getCollectionName());
logger.info("Registering RESTful API resources");
env.jersey().register(new PingResource());
env.jersey().register(new EmployeeResource(collection, new MongoService()));
env.healthChecks().register("DropwizardMongoDBHealthCheck",
new DropwizardMongoDBHealthCheckResource(mongoClient));
}
}
I have used these steps and written a blog post and a sample working application code is available on GitHub. Please check: http://softwaredevelopercentral.blogspot.com/2017/09/dropwizard-mongodb-tutorial.html

Adding applicationproperties in Jhipster

I'm using jhipster microservices app for my development. Based on jhipster documentation for adding application-specific is here:
application-dev.yml and
ApplicationProperties.java
I did this by adding this
application:
mycom:
sgADIpAddress: 172.x.x.xxx
and this my applicationconfig class
package com.mbb.ias.config;
import org.springframework.boot.context.properties.ConfigurationProperties;
/**
* Properties specific to JHipster.
*
* <p>
* Properties are configured in the application.yml file.
* </p>
*/
#ConfigurationProperties(prefix = "application", ignoreUnknownFields = false)
public class ApplicationProperties {
private final Mycom mycom= new Mycom();
public Mycom getMycom () {
return mycom;
}
public static class Mycom {
String sgADIpAddress ="";
public String getSgADIpAddress() {
return sgADIpAddress;
}
public void setSgADIpAddress(String sgADIpAddress) {
this.sgADIpAddress = sgADIpAddress;
}
}
}
I've call this by using same like jhipster properties which are
#Inject
private ApplicationProperties applicationProperties;
in classes which are need this AD IP address.
it will throw null value
java.lang.NumberFormatException: null
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
please help me guys, SIT going to be started, I need to create a profile for maven build like jhipster created

I have the same problem and spent a couple of hours to figure it out...Jhipster has its preconfigured property class that users can customize their own properteis:
Quote from Jhipster website:
Your generated application can also have its own Spring Boot properties. This is highly recommended, as it allows type-safe configuration of the application, as well as auto-completion and documentation within an IDE.
JHipster has generated a ApplicationProperties class in the config package, which is already preconfigured, and it is already documented at the bottom the application.yml, application-dev.yml and application-prod.yml files. All you need to do is code your own specific properties.
In my case, I have set the properties in all yml files.
application:
redis:
host: vnode1
pool:
max-active: 8
max-idle: 8
max-wait: -1
min-idle: 0
port: 6379
In ApplicationProperties class:
#ConfigurationProperties(prefix = "application", ignoreUnknownFields = false)
public class ApplicationProperties {
public final Redis redis = new Redis();
public Redis getRedis() {
return redis;
}
public static class Redis {
private String host = "127.0.0.1";
private int port = 0;
public String getHost() {
return host;
}
public void setHost(String host) {
this.host = host;
}
public int getPort() {
return port;
}
public void setPort(int port) {
this.port = port;
}
private Pool pool = new Pool();
public void setPool(Pool pool) {
this.pool = pool;
}
public Pool getPool() {
return this.pool;
}
public static class Pool {
private int maxActive = 8;
private int maxWait = -1;
private int maxIdle = 8;
private int minIdle = 0;
public int getMaxIdle() {
return maxIdle;
}
public void setMaxIdle(int maxIdle) {
this.maxIdle = maxIdle;
}
public void setMaxActive(int maxActive) {
this.maxActive = maxActive;
}
public int getMaxActive() {
return maxActive;
}
public int getMinIdle() {
return minIdle;
}
public void setMinIdle(int minIdle) {
this.minIdle = minIdle;
}
public int getMaxWait() {
return maxWait;
}
public void setMaxWait(int maxWait) {
this.maxWait = maxWait;
}
}
}
}
Then I use it as:
private final ApplicationProperties.Redis redis;
public RedisConfiguration(ApplicationProperties applicationProperties){
redis = applicationProperties.getRedis();
}
For instance use max-wait and host:
this.redis.getPool().getMaxWait();
this.redis.getHost();

refering to this thread
Spring annotation #Inject doesn't work
i remove my new operator for all classes which is calling my applicationproperties.java
#Service
public class ADAuthenticatorService {
private static final Logger log = LoggerFactory.getLogger(ADAuthenticatorService.class);
private final static long DIFF_NET_JAVA_FOR_DATE_AND_TIMES = 11644473600000L;
#Inject
ADContext adContext;
/**
* AD authentication
*
* #param UserID,
* AD User ID
* #param Password,
* AD Password
* #return ADProfile
*/
#Inject
ApplicationProperties applicationProperties;
public ADProfile authenticate(String UserID, String Password) throws Exception {
ADContext context = adContext.getDefaultContext(applicationProperties);
return authenticate(context, UserID, Password);
}
in my ADContext i put #component on the top of my Class name, and added #Sevice annotation on the top of ADAuthenticatorService
then my
#Inject
ApplicationProperties applicationProperties;
is working flawlessly
just posting this answer so any noob like me at outside can benefit this lol

Can't make messageSource work in the Pojo classes

I am not being able to make messageSource work in the Pojo classes,its throwing a nullpointerexception. However in all the other classes namely controller,service messageSource is working alright. Could someone please suggest what needs to be done ?
#Autowired
private MessageSource messageSource;
I have autowired the MessageSource using the above code snippet.
public class ProposalWiseSelectionForm implements Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
#Autowired
private MessageSource messageSource;
private String txtPageHierarchy="";
private String txtLineOfBusiness;
private String txtProduct;
private String btn;
private String clickedGo="N";
private List arrLineOfBusiness=new ArrayList();
private List arrProduct=new ArrayList();
#Valid
private ArrayList documentList=initiateDocumentList();
private String txtPageMode="I";
private String enableDiscardBtn="N";
private String enableInsertBtn="N";
private String isDivVisible="N";
private int numApplicationType=1;
public ProposalWiseSelectionForm() {
}
public String getTxtPageHierarchy() {
return txtPageHierarchy;
}
public void setTxtPageHierarchy(String txtPageHierarchy) {
this.txtPageHierarchy = txtPageHierarchy;
}
public String getTxtLineOfBusiness() {
return txtLineOfBusiness;
}
public void setTxtLineOfBusiness(String txtLineOfBusiness) {
this.txtLineOfBusiness = txtLineOfBusiness;
}
public String getTxtProduct() {
return txtProduct;
}
public void setTxtProduct(String txtProduct) {
this.txtProduct = txtProduct;
}
public String getBtn() {
return btn;
}
public void setBtn(String btn) {
this.btn = btn;
}
public String getClickedGo() {
return clickedGo;
}
public void setClickedGo(String clickedGo) {
this.clickedGo = clickedGo;
}
public List getArrLineOfBusiness() {
return arrLineOfBusiness;
}
public void setArrLineOfBusiness(List arrLineOfBusiness) {
this.arrLineOfBusiness = arrLineOfBusiness;
}
public List getArrProduct() {
return arrProduct;
}
public void setArrProduct(List arrProduct) {
this.arrProduct = arrProduct;
}
public void setArrProduct(ArrayList arrProduct) {
this.arrProduct = arrProduct;
}
public ArrayList getDocumentList() {
return documentList;
}
public void setDocumentList(ArrayList documentList) {
this.documentList = documentList;
}
public String getTxtPageMode() {
return txtPageMode;
}
public void setTxtPageMode(String txtPageMode) {
this.txtPageMode = txtPageMode;
}
public String getEnableDiscardBtn() {
return enableDiscardBtn;
}
public void setEnableDiscardBtn(String enableDiscardBtn) {
this.enableDiscardBtn = enableDiscardBtn;
}
public String getEnableInsertBtn() {
return enableInsertBtn;
}
public void setEnableInsertBtn(String enableInsertBtn) {
this.enableInsertBtn = enableInsertBtn;
}
public String getIsDivVisible() {
return isDivVisible;
}
public void setIsDivVisible(String isDivVisible) {
this.isDivVisible = isDivVisible;
}
public int getNumApplicationType() {
return numApplicationType;
}
public void setNumApplicationType(int numApplicationType) {
this.numApplicationType = numApplicationType;
}
}

In order to be able to use #Autowired in a class, that class has to be managed by Spring.
of
Your ProposalWiseSelectionForm class is obviously not managed by Spring and therefor messageSource is always null.
Using #Autowired MessageSource messageSource in your other classes works, because as you mention those classes are managed by Spring (as you have mentioned they are either controllers, services etc).
I am guessing that ProposalWiseSelectionForm is a DTO used to capture values from a form. The sort of class will not be a Spring bean and therefor you can't autowire stuff into it.
I suggest you either move the logic you need out of the DTO and into the controller (or some Spring managed utility) or in the extreme case that you absolutely need #Autowired in the DTO, take a look at #Configurable here and here

Try using #Component,you might be getting this issue because of the fact the Pojo class is not being recognized.

You have to make your class a Spring bean
Add #Component annotation to your class and add these 2 lines to your appContext.xml:
<context:component-scan base-package="com.<your-company-name>" />
<context:annotation-config />
Or just add the service in your beans section in the appContext.xml if you wish not to work with Spring component-scan feature.