Skip navigation links

Package io.vertx.ext.mongo

= Vert.x MongoDB Client A Vert.x client allowing applications to interact with a MongoDB instance, whether that's saving, retrieving, searching, or deleting documents.

See: Description

Package io.vertx.ext.mongo Description

= Vert.x MongoDB Client A Vert.x client allowing applications to interact with a MongoDB instance, whether that's saving, retrieving, searching, or deleting documents. Mongo is a great match for persisting data in a Vert.x application as it natively handles JSON (BSON) documents. *Features* * Completely non-blocking * Custom codec to support fast serialization to/from Vert.x JSON * Supports a majority of the configuration options from the MongoDB Java Driver This client is based on the http://mongodb.github.io/mongo-java-driver/3.2/driver-async/getting-started[MongoDB Async Driver]. == Using Vert.x MongoDB Client To use this project, add the following dependency to the _dependencies_ section of your build descriptor: * Maven (in your `pom.xml`): [source,xml,subs="+attributes"] ---- ${maven.groupId} ${maven.artifactId} ${maven.version} ---- * Gradle (in your `build.gradle` file): [source,groovy,subs="+attributes"] ---- compile '${maven.groupId}:${maven.artifactId}:${maven.version}' ---- == Creating a client You can create a client in several ways: === Using the default shared pool In most cases you will want to share a pool between different client instances. E.g. you scale your application by deploying multiple instances of your verticle and you want each verticle instance to share the same pool so you don't end up with multiple pools The simplest way to do this is as follows: [source,$lang] ---- examples.Examples#exampleCreateDefault ---- The first call to MongoClient.createShared(io.vertx.core.Vertx, io.vertx.core.json.JsonObject) will actually create the pool, and the specified config will be used. Subsequent calls will return a new client instance that uses the same pool, so the configuration won't be used. === Specifying a pool source name You can create a client specifying a pool source name as follows [source,$lang] ---- examples.Examples#exampleCreatePoolName ---- If different clients are created using the same Vert.x instance and specifying the same pool name, they will share the same pool. The first call to MongoClient.createShared(io.vertx.core.Vertx, io.vertx.core.json.JsonObject) will actually create the pool, and the specified config will be used. Subsequent calls will return a new client instance that uses the same pool, so the configuration won't be used. Use this way of creating if you wish different groups of clients to have different pools, e.g. they're interacting with different databases. === Creating a client with a non shared data pool In most cases you will want to share a pool between different client instances. However, it's possible you want to create a client instance that doesn't share its pool with any other client. In that case you can use MongoClient.createNonShared(io.vertx.core.Vertx, io.vertx.core.json.JsonObject). [source,$lang] ---- examples.Examples#exampleCreateNonShared ---- This is equivalent to calling MongoClient.createShared(io.vertx.core.Vertx, io.vertx.core.json.JsonObject, String) with a unique pool name each time. == Using the API The client API is represented by MongoClient. === Saving documents To save a document you use MongoClient.save(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.lang.String>>). If the document has no `\_id` field, it is inserted, otherwise, it is __upserted__. Upserted means it is inserted if it doesn't already exist, otherwise it is updated. If the document is inserted and has no id, then the id field generated will be returned to the result handler. Here's an example of saving a document and getting the id back [source,$lang] ---- examples.Examples#example1 ---- And here's an example of saving a document which already has an id. [source,$lang] ---- examples.Examples#example2 ---- === Inserting documents To insert a document you use MongoClient.insert(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.lang.String>>). If the document is inserted and has no id, then the id field generated will be returned to the result handler. [source,$lang] ---- examples.Examples#example3 ---- If a document is inserted with an id, and a document with that id already exists, the insert will fail: [source,$lang] ---- examples.Examples#example4 ---- === Updating documents To update a documents you use MongoClient.updateCollection(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.ext.mongo.MongoClientUpdateResult>>). This updates one or multiple documents in a collection. The json object that is passed in the `updateCollection` parameter must contain http://docs.mongodb.org/manual/reference/operator/update-field/[Update Operators] and determines how the object is updated. The json object specified in the query parameter determines which documents in the collection will be updated. Here's an example of updating a document in the books collection: [source,$lang] ---- examples.Examples#example5 ---- To specify if the update should upsert or update multiple documents, use MongoClient.updateCollectionWithOptions(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.json.JsonObject, io.vertx.ext.mongo.UpdateOptions, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.ext.mongo.MongoClientUpdateResult>>) and pass in an instance of UpdateOptions. This has the following fields: `multi`:: set to true to update multiple documents `upsert`:: set to true to insert the document if the query doesn't match `writeConcern`:: the write concern for this operation [source,$lang] ---- examples.Examples#example6 ---- === Replacing documents To replace documents you use MongoClient.replaceDocuments(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.ext.mongo.MongoClientUpdateResult>>). This is similar to the update operation, however it does not take any operator. Instead it replaces the entire document with the one provided. Here's an example of replacing a document in the books collection [source,$lang] ---- examples.Examples#example7 ---- === Bulk operations To execute multiple insert, update, replace, or delete operations at once, use MongoClient.bulkWrite(java.lang.String, java.util.List<io.vertx.ext.mongo.BulkOperation>, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.ext.mongo.MongoClientBulkWriteResult>>). You can pass a list of BulkOperations, with each working similar to the matching single operation. You can pass as many operations, even of the same type, as you wish. To specify if the bulk operation should be executed in order, and with what write option, use MongoClient.bulkWriteWithOptions(java.lang.String, java.util.List<io.vertx.ext.mongo.BulkOperation>, io.vertx.ext.mongo.BulkWriteOptions, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.ext.mongo.MongoClientBulkWriteResult>>) and pass an instance of BulkWriteOptions. For more explanation what ordered means, see https://docs.mongodb.com/manual/reference/method/db.collection.bulkWrite/#execution-of-operations[Execution of Operations]. === Finding documents To find documents you use MongoClient.find(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.util.List<io.vertx.core.json.JsonObject>>>). The `query` parameter is used to match the documents in the collection. Here's a simple example with an empty query that will match all books: [source,$lang] ---- examples.Examples#example8 ---- Here's another example that will match all books by Tolkien: [source,$lang] ---- examples.Examples#example9 ---- The matching documents are returned as a list of json objects in the result handler. To specify things like what fields to return, how many results to return, etc use MongoClient.findWithOptions(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.ext.mongo.FindOptions, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.util.List<io.vertx.core.json.JsonObject>>>) and pass in the an instance of FindOptions. This has the following fields: `fields`:: The fields to return in the results. Defaults to `null`, meaning all fields will be returned `sort`:: The fields to sort by. Defaults to `null`. `limit`:: The limit of the number of results to return. Default to `-1`, meaning all results will be returned. `skip`:: The number of documents to skip before returning the results. Defaults to `0`. === Finding documents in batches When dealing with large data sets, it is not advised to use the MongoClient.find(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.util.List<io.vertx.core.json.JsonObject>>>) and MongoClient.findWithOptions(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.ext.mongo.FindOptions, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.util.List<io.vertx.core.json.JsonObject>>>) methods. In order to avoid inflating the whole response into memory, use MongoClient.findBatch(java.lang.String, io.vertx.core.json.JsonObject): [source,$lang] ---- examples.Examples#findBatch ---- The matching documents are emitted one by one by the ReadStream handler. FindOptions has an extra parameter `batchSize` which you can use to set the number of documents to load at once: [source,$lang] ---- examples.Examples#findBatchWithOptions ---- By default, `batchSize` is set to 20. === Finding a single document To find a single document you use MongoClient.findOne(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.core.json.JsonObject>>). This works just like MongoClient.find(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.util.List<io.vertx.core.json.JsonObject>>>) but it returns just the first matching document. === Removing documents To remove documents use MongoClient.removeDocuments(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.ext.mongo.MongoClientDeleteResult>>). The `query` parameter is used to match the documents in the collection to determine which ones to remove. Here's an example of removing all Tolkien books: [source,$lang] ---- examples.Examples#example10 ---- === Removing a single document To remove a single document you use MongoClient.removeDocument(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.ext.mongo.MongoClientDeleteResult>>). This works just like MongoClient.removeDocuments(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.ext.mongo.MongoClientDeleteResult>>) but it removes just the first matching document. === Counting documents To count documents use MongoClient.count(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.lang.Long>>). Here's an example that counts the number of Tolkien books. The number is passed to the result handler. [source,$lang] ---- examples.Examples#example11 ---- === Managing MongoDB collections All MongoDB documents are stored in collections. To get a list of all collections you can use MongoClient.getCollections(io.vertx.core.Handler<io.vertx.core.AsyncResult<java.util.List<java.lang.String>>>) [source,$lang] ---- examples.Examples#example11_1 ---- To create a new collection you can use MongoClient.createCollection(java.lang.String, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.lang.Void>>) [source,$lang] ---- examples.Examples#example11_2 ---- To drop a collection you can use MongoClient.dropCollection(java.lang.String, io.vertx.core.Handler<io.vertx.core.AsyncResult<java.lang.Void>>) NOTE: Dropping a collection will delete all documents within it! [source,$lang] ---- examples.Examples#example11_3 ---- === Running other MongoDB commands You can run arbitrary MongoDB commands with MongoClient.runCommand(java.lang.String, io.vertx.core.json.JsonObject, io.vertx.core.Handler<io.vertx.core.AsyncResult<io.vertx.core.json.JsonObject>>). Commands can be used to run more advanced MongoDB features, such as using MapReduce. For more information see the mongo docs for supported http://docs.mongodb.org/manual/reference/command[Commands]. Here's an example of running an aggregate command. Note that the command name must be specified as a parameter and also be contained in the JSON that represents the command. This is because JSON is not ordered but BSON is ordered and MongoDB expects the first BSON entry to be the name of the command. In order for us to know which of the entries in the JSON is the command name it must be specified as a parameter. [source,$lang] ---- examples.Examples#example12 ---- === MongoDB Extended JSON support For now, only `date`, `oid` and `binary` types are supported (see http://docs.mongodb.org/manual/reference/mongodb-extended-json[MongoDB Extended JSON]). Here's an example of inserting a document with a `date` field: [source,$lang] ---- examples.Examples#example13_0 ---- Here's an example (in Java) of inserting a document with a binary field and reading it back [source,$lang] ---- examples.Examples#example14_01_dl ---- Here's an example of inserting a base 64 encoded string, typing it as binary a binary field, and reading it back [source,$lang] ---- examples.Examples#example14_02_dl ---- Here's an example of inserting an object ID and reading it back [source,$lang] ---- examples.Examples#example15_dl ---- === Getting distinct values Here's an example of getting distinct value [source,$lang] ---- examples.Examples#example16 ---- Here's an example of getting distinct value in batch mode [source,$lang] ---- examples.Examples#example16_d1 ---- * Here's an example of getting distinct value with query [source,$lang] ---- examples.Examples#example17 ---- Here's an example of getting distinct value in batch mode with query [source,$lang] ---- examples.Examples#example17_d1 ---- == Configuring the client The client is configured with a json object. The following configuration is supported by the mongo client: `db_name`:: Name of the database in the MongoDB instance to use. Defaults to `default_db` `useObjectId`:: Toggle this option to support persisting and retrieving ObjectId's as strings. If `true`, hex-strings will be saved as native Mongodb ObjectId types in the document collection. This will allow the sorting of documents based on creation time. You can also derive the creation time from the hex-string using ObjectId::getDate(). Set to `false` for other types of your choosing. If set to false, or left to default, hex strings will be generated as the document _id if the _id is omitted from the document. Defaults to `false`. The mongo client tries to support most options that are allowed by the driver. There are two ways to configure mongo for use by the driver, either by a connection string or by separate configuration options. NOTE: If the connection string is used the mongo client will ignore any driver configuration options. `connection_string`:: The connection string the driver uses to create the client. E.g. `mongodb://localhost:27017`. For more information on the format of the connection string please consult the driver documentation. *Specific driver configuration options* [source,js] ---- { // Single Cluster Settings "host" : "127.0.0.1", // string "port" : 27017, // int // Multiple Cluster Settings "hosts" : [ { "host" : "cluster1", // string "port" : 27000 // int }, { "host" : "cluster2", // string "port" : 28000 // int }, ... ], "replicaSet" : "foo", // string "serverSelectionTimeoutMS" : 30000, // long // Connection Pool Settings "maxPoolSize" : 50, // int "minPoolSize" : 25, // int "maxIdleTimeMS" : 300000, // long "maxLifeTimeMS" : 3600000, // long "waitQueueMultiple" : 10, // int "waitQueueTimeoutMS" : 10000, // long "maintenanceFrequencyMS" : 2000, // long "maintenanceInitialDelayMS" : 500, // long // Credentials / Auth "username" : "john", // string "password" : "passw0rd", // string "authSource" : "some.db" // string // Auth mechanism "authMechanism" : "GSSAPI", // string "gssapiServiceName" : "myservicename", // string // Socket Settings "connectTimeoutMS" : 300000, // int "socketTimeoutMS" : 100000, // int "sendBufferSize" : 8192, // int "receiveBufferSize" : 8192, // int "keepAlive" : true // boolean // Heartbeat socket settings "heartbeat.socket" : { "connectTimeoutMS" : 300000, // int "socketTimeoutMS" : 100000, // int "sendBufferSize" : 8192, // int "receiveBufferSize" : 8192, // int "keepAlive" : true // boolean } // Server Settings "heartbeatFrequencyMS" : 1000 // long "minHeartbeatFrequencyMS" : 500 // long } ---- *Driver option descriptions* `host`:: The host the MongoDB instance is running. Defaults to `127.0.0.1`. This is ignored if `hosts` is specified `port`:: The port the MongoDB instance is listening on. Defaults to `27017`. This is ignored if `hosts` is specified `hosts`:: An array representing the hosts and ports to support a MongoDB cluster (sharding / replication) `host`:: A host in the cluster `port`:: The port a host in the cluster is listening on `replicaSet`:: The name of the replica set, if the MongoDB instance is a member of a replica set `serverSelectionTimeoutMS`:: The time in milliseconds that the mongo driver will wait to select a server for an operation before raising an error. `maxPoolSize`:: The maximum number of connections in the connection pool. The default value is `100` `minPoolSize`:: The minimum number of connections in the connection pool. The default value is `0` `maxIdleTimeMS`:: The maximum idle time of a pooled connection. The default value is `0` which means there is no limit `maxLifeTimeMS`:: The maximum time a pooled connection can live for. The default value is `0` which means there is no limit `waitQueueMultiple`:: The maximum number of waiters for a connection to become available from the pool. Default value is `500` `waitQueueTimeoutMS`:: The maximum time that a thread may wait for a connection to become available. Default value is `120000` (2 minutes) `maintenanceFrequencyMS`:: The time period between runs of the maintenance job. Default is `0`. `maintenanceInitialDelayMS`:: The period of time to wait before running the first maintenance job on the connection pool. Default is `0`. `username`:: The username to authenticate. Default is `null` (meaning no authentication required) `password`:: The password to use to authenticate. `authSource`:: The database name associated with the user's credentials. Default value is the `db_name` value. `authMechanism`:: The authentication mechanism to use. See [Authentication](http://docs.mongodb.org/manual/core/authentication/) for more details. `gssapiServiceName`:: The Kerberos service name if `GSSAPI` is specified as the `authMechanism`. `connectTimeoutMS`:: The time in milliseconds to attempt a connection before timing out. Default is `10000` (10 seconds) `socketTimeoutMS`:: The time in milliseconds to attempt a send or receive on a socket before the attempt times out. Default is `0` meaning there is no timeout `sendBufferSize`:: Sets the send buffer size (SO_SNDBUF) for the socket. Default is `0`, meaning it will use the OS default for this option. `receiveBufferSize`:: Sets the receive buffer size (SO_RCVBUF) for the socket. Default is `0`, meaning it will use the OS default for this option. `keepAlive`:: Sets the keep alive (SO_KEEPALIVE) for the socket. Default is `false` `heartbeat.socket`:: Configures the socket settings for the cluster monitor of the MongoDB java driver. `heartbeatFrequencyMS`:: The frequency that the cluster monitor attempts to reach each server. Default is `5000` (5 seconds) `minHeartbeatFrequencyMS`:: The minimum heartbeat frequency. The default value is `1000` (1 second) NOTE: Most of the default values listed above use the default values of the MongoDB Java Driver. Please consult the driver documentation for up to date information.
Skip navigation links

Copyright © 2018 Eclipse. All rights reserved.