- Introduction
- Supported types
- Supported operations
- Defining modules
- Deploying modules
- Publishing events
- Java Flight Recorder support
- Requirements
- Installation
- Release process
vertx-mongodb-effect allows us to work with MongoDB following a purely functional and reactive style. It requires to be familiar with vertx-effect. Both vertx-effect and vertx-mongo-effect use the immutable and persistent Json from json-values. Jsons travel across the event bus, from verticle to verticle, back and forth, without being neither copied nor converted to BSON. The vertx codecs to send the Json from json-values to the event bus are in vertx-values, which is a dependency of vertx-effect.
json-values supports the standard Json types: string, number, null, object, array; There are five number specializations: int, long, double, decimal, and BigInteger. json-values adds support for instants and binary data. It serializes Instants into its string representation according to ISO-8601, and the binary type into a string encoded in base 64.
vertx-mongodb-effect uses mongo-values. It abstracts the processes of encoding to BSON and decoding from BSON. Please find below the BSON types supported and their equivalent types in json-values.
Map<BsonType, Class<?>> map = new HashMap<>();
map.put(BsonType.NULL, JsNull.class);
map.put(BsonType.ARRAY, JsArray.class);
map.put(BsonType.BINARY, JsBinary.class);
map.put(BsonType.BOOLEAN, JsBool.class);
map.put(BsonType.DATE_TIME, JsInstant.class);
map.put(BsonType.DOCUMENT, JsObj.class);
map.put(BsonType.DOUBLE, JsDouble.class);
map.put(BsonType.INT32, JsInt.class);
map.put(BsonType.INT64, JsLong.class);
map.put(BsonType.DECIMAL128, JsBigDec.class);
map.put(BsonType.STRING, JsStr.class);
When defining the mongodb settings, you have to specify the codec registry JsValuesRegistry from mongo-values:
import com.mongodb.ConnectionString;
import com.mongodb.MongoClientSettings;
import mongovalues.JsValuesRegistry;
MongoClientSettings settings =
MongoClientSettings.builder()
.applyConnectionString(connString)
.codecRegistry(JsValuesRegistry.INSTANCE)
.build();
Every method of the MongoDB driver has an associated lambda.
Since vertx-mongodb-effect uses the driver API directly, it can benefit from all its features and methods. It's an advantage over the official vertx-mongodb-client.
Please find below the types and constructors of the most essentials operations:
Count :: Lambdac<JsObj, Long>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.model.CountOptions;
public Count(Supplier<MongoCollection<JsObj>> collectionSupplier,
CountOptions options
)
DeleteMany :: Lambdac<JsObj, O>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.model.DeleteOptions;
import com.mongodb.client.result.DeleteResult;
public DeleteMany(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<DeleteResult, O> resultConverter,
DeleteOptions options
)
DeleteOne :: Lambdac<JsObj, O>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.model.DeleteOptions;
import com.mongodb.client.result.DeleteResult;
public DeleteOne(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<DeleteResult, O> resultConverter,
DeleteOptions options
)
FindAll :: Lambdac<FindMessage, JsArray>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.FindIterable;
public FindAll(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<FindIterable<JsObj>, JsArray> converter
)
FindOne :: Lambdac<FindMessage, JsObj>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.FindIterable;
public FindOne(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<FindIterable<JsObj>, JsObj> converter
)
FindOneAndDelete :: Lambdac<JsObj, JsObj>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.model.FindOneAndDeleteOptions;
public FindOneAndDelete(Supplier<MongoCollection<JsObj>> collectionSupplier,
FindOneAndDeleteOptions options
)
FindOneAndReplace :: Lambdac<UpdateMessage, JsObj>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.model.FindOneAndReplaceOptions;
public FindOneAndReplace(Supplier<MongoCollection<JsObj>> collectionSupplier,
FindOneAndReplaceOptions options
)
FindOneAndUpdate :: Lambdac<UpdateMessage, JsObj>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.model.FindOneAndUpdateOptions;
public FindOneAndUpdate(Supplier<MongoCollection<JsObj>> collectionSupplier,
FindOneAndUpdateOptions options
)
InsertMany :: Lambdac<JsArray, R>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.result.InsertManyResult;
import com.mongodb.client.model.InsertManyOptions;
public InsertMany(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<InsertManyResult, R> resultConverter,
InsertManyOptions options
)
InsertOne :: Lambdac<JsObj, R>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.result.InsertOneResult;
import com.mongodb.client.model.InsertOneOptions;
public InsertOne(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<InsertOneResult, R> resultConverter,
InsertOneOptions options
)
ReplaceOne :: Lambdac<UpdateMessage, O>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.result.UpdateResult;
import com.mongodb.client.model.ReplaceOptions;
public ReplaceOne(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<UpdateResult, O> resultConverter,
ReplaceOptions options
)
UpdateMany :: Lambdac<UpdateMessage, O>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.result.UpdateResult;
import com.mongodb.client.model.UpdateOptions
public UpdateMany(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<UpdateResult, O> resultConverter,
UpdateOptions options
)
UpdateOne :: Lambdac<UpdateMessage, O>
import com.mongodb.client.MongoCollection;
import com.mongodb.client.result.UpdateResult;
import com.mongodb.client.model.UpdateOptions
public UpdateOne(Supplier<MongoCollection<JsObj>> collectionSupplier,
Function<UpdateResult, O> resultConverter,
UpdateOptions options
)
Like with vertx-effect, modules deploys verticles and expose lambdas to communicate with them. The typical scenario is to create a module per collection. We can deploy or spawn verticles.
The following modules are just a couple of examples.
We create a module where all the lambdas make read operations and spawn verticles to reach a significant level of parallelization:
import vertx.mongodb.effect.MongoModule;
import vertx.effect.Lambdac;
public class ReadModule extends MongoModule {
public MyCollectionModule(final Supplier<MongoCollection<JsObj>> collection) {
super(collection);
}
public static Lambdac<FindMessage, Optional<JsObj>> findOne;
public static Lambdac<FindMessage, JsArray> findAll;
public static Lambdac<JsObj, Long> count;
public static Lambdac<JsArray, JsArray> aggregate;
@Override
protected void deploy() {}
@Override
protected void initialize() {
Lambdac<FindMessage, JsObj> findOneLambda = vertxRef.spawn("find_one",
new FindOne(collection)
);
this.findOne = (context,message) -> findOneLambda.apply(context,message)
.map(Optional::ofNullable);
this.findAll = vertxRef.spawn("find_all",
new FindAll(collection)
);
this.count = vertxRef.spawn("count",
new Count(collection)
);
this.aggregate = vertxRef.spawn("aggregate",
new Aggregate<>(collection,
Converters.aggregateResult2JsArray
)
);
}
}
We create a module where all the lambdas make delete, insert and update operations, and deploy only one instance per verticle.
import vertx.mongodb.effect.MongoModule;
import vertx.effect.Lambdac;
public class MyCollectionModule extends MongoModule {
public MyCollectionModule(final Supplier<MongoCollection<JsObj>> collection) {
super(collection);
}
public static Lambdac<JsObj, String> insertOne;
public static Lambdac<JsObj, JsObj> deleteOne;
public static Lambdac<UpdateMessage, JsObj> replaceOne;
public static Lambdac<UpdateMessage, JsObj> updateOne;
@Override
protected void deploy() {
this.deploy(INSERT_ONE_ADDRESS,
new InsertOne<>(collection,
Converters.insertOneResult2HexId
),
);
this.deploy(DELETE_ONE_ADDRESS,
new DeleteOne<>(collection,
Converters.deleteResult2JsObj
)
);
this.deploy(REPLACE_ONE_ADDRESS,
new ReplaceOne<>(collection,
Converters.updateResult2JsObj
)
);
this.deploy(UPDATE_ONE_ADDRESS,
new UpdateOne<>(collection,
Converters.updateResult2JsObj
)
);
}
@Override
protected void initialize() {
this.insertOne = this.trace(INSERT_ONE_ADDRESS);
this.deleteOne = this.trace(DELETE_ONE_ADDRESS);
this.replaceOne = this.trace(REPLACE_ONE_ADDRESS);
this.updateOne = this.trace(UPDATE_ONE_ADDRESS);
}
private static final String DELETE_ONE_ADDRESS = "delete_one";
private static final String UPDATE_ONE_ADDRESS = "update_one";
private static final String REPLACE_ONE_ADDRESS = "replace_one";
private static final String INSERT_ONE_ADDRESS = "insert_one";
private static final String INSERT_MANY_ADDRESS = "insert_all";
private static final String DELETE_MANY_ADDRESS = "delete_all";
}
The verticles RegisterMongoEffectCodecs and RegisterJsValuesCodecs need to be deployed to register the vertx message codecs. Remember that you can't send any message to the event bus. If a message is not supported by Vertx you have to create a MessageCodec.
import com.mongodb.ConnectionString;
import com.mongodb.MongoClientSettings;
import vertx.mongodb.effect.MongoVertxClient;
import vertx.effect.VertxRef;
// define every timeout if you wanna be reactive
int connectTimeoutMS = ???;
int socketTimeoutMS = ???;
int serverSelectionTimeoutMS = ???;
String connectionUrl =
String.format("mongodb://localhost:27017/?connectTimeoutMS=%s&socketTimeoutMS=%s&serverSelectionTimeoutMS=%s",
connectTimeoutMS,
socketTimeoutMS,
serverSelectionTimeoutMS
);
ConnectionString connString = new ConnectionString(connectionUrl);
MongoClientSettings settings =
MongoClientSettings.builder()
.applyConnectionString(connString)
.codecRegistry(JsValuesRegistry.INSTANCE)
.build();
// one vertx client per database connection
MongoVertxClient mongoClient = new MongoVertxClient(settings);
String database = ???;
String collection = ???;
MyCollectionModule collectionModule =
new MyCollectionModule(mongoClient.getCollection(database,
collection
)
);
VertxRef vertxRef = new VertxRef(vertx);
Quadruple.sequential(vertxRef.deployVerticle(new RegisterJsValuesCodecs()),
vertxRef.deployVerticle(new RegisterMongoEffectCodecs()),
vertxRef.deployVerticle(mongoClient),
vertxRef.deployVerticle(collectionModule)
)
.get();
Once everything is up and running, enjoy your lambdas!
BiFunction<Integer,String,Val<Optional<JsObj>>> findByCode = (attempts,code) ->
MyCollectionModule.findOne
.apply(FindMessage.ofFilter(JsObj.of("code",
JsStr.of(code)
)
)
)
.retry(e -> Failures.anyOf(MONGO_CONNECT_TIMEOUT_CODE,
MONGO_READ_TIMEOUT_CODE
),
attempts
)
.recoverWith(e -> Val.succeed(Optional.empty()));
Since vertx-effect publishes the most critical events into the address vertx-effect-events, it' possible to register consumers to explode that information. You can disable this feature with the Java system property -Dpublish.events=false. Thanks to Lambdac, it's possible to correlate different events that belongs to the same transaction. Go to the vertx-effect doc for further details.
Since vertx-effect supports JFR, all the verticle messages have an associated event and can be visualized using Java Mission Control.
Fields of a verticle message event:
- address: Address of the Verticle where the message is sent to
- result: SUCCESS OR FAILURE, dependening on what the caller receives
- failure code: In case the failure is a ReplyException, it's the failure code
- failure type: In case the failure is a ReplyException, it's the failure type
- failure message: In case the failure is a ReplyException, it's the failure message
- exception class: In case the failure is not a ReplyException, it's the exception class name
- exception message: In case the failure is not a ReplyException, it's the exception message
- duration: time since the message is sent until the response is received
- Java 17 or greater
- vertx-effect
- mongo driver sync
- Mongo values
<dependency>
<groupId>com.github.imrafaelmerino</groupId>
<artifactId>vertx-mongodb-effect</artifactId>
<version>2.0.0</version>
</dependency>
