= 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
https://mongodb.github.io/mongo-java-driver/4.1/driver-reactive/getting-started/quick-start/[MongoDB ReactiveStreams 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"]
----
<dependency>
  <groupId>io.vertx</groupId>
  <artifactId>vertx-mongo-client</artifactId>
  <version>${maven.version}</version>
</dependency>
----

* Gradle (in your `build.gradle` file):

[source,groovy,subs="+attributes"]
----
compile 'io.vertx:vertx-mongo-client:${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]
----
{@link examples.MongoClientExamples#exampleCreateDefault}
----

The first call to {@link io.vertx.ext.mongo.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]
----
{@link examples.MongoClientExamples#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 {@link io.vertx.ext.mongo.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 {@link io.vertx.ext.mongo.MongoClient#create(io.vertx.core.Vertx, io.vertx.core.json.JsonObject)}.

[source,$lang]
----
{@link examples.MongoClientExamples#exampleCreateNonShared}
----

This is equivalent to calling {@link io.vertx.ext.mongo.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 {@link io.vertx.ext.mongo.MongoClient}.

=== Saving documents

To save a document you use {@link io.vertx.ext.mongo.MongoClient#save}.

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]
----
{@link examples.MongoClientExamples#example1}
----

And here's an example of saving a document which already has an id.

[source,$lang]
----
{@link examples.MongoClientExamples#example2}
----

=== Inserting documents

To insert a document you use {@link io.vertx.ext.mongo.MongoClient#insert}.

If the document is inserted and has no id, then the id field generated will be returned to the result handler.

[source,$lang]
----
{@link examples.MongoClientExamples#example3}
----

If a document is inserted with an id, and a document with that id already exists, the insert will fail:

[source,$lang]
----
{@link examples.MongoClientExamples#example4}
----

=== Updating documents

To update a documents you use {@link io.vertx.ext.mongo.MongoClient#updateCollection}.

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]
----
{@link examples.MongoClientExamples#example5}
----

To specify if the update should upsert or update multiple documents, use
{@link io.vertx.ext.mongo.MongoClient#updateCollectionWithOptions}
and pass in an instance of {@link io.vertx.ext.mongo.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]
----
{@link examples.MongoClientExamples#example6}
----

=== Replacing documents

To replace documents you use {@link io.vertx.ext.mongo.MongoClient#replaceDocuments}.

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]
----
{@link examples.MongoClientExamples#example7}
----

=== Bulk operations

To execute multiple insert, update, replace, or delete operations at once, use {@link io.vertx.ext.mongo.MongoClient#bulkWrite}.

You can pass a list of {@link io.vertx.ext.mongo.BulkOperation 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 {@link io.vertx.ext.mongo.MongoClient#bulkWriteWithOptions}
and pass an instance of {@link io.vertx.ext.mongo.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 {@link io.vertx.ext.mongo.MongoClient#find}.

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]
----
{@link examples.MongoClientExamples#example8}
----

Here's another example that will match all books by Tolkien:

[source,$lang]
----
{@link examples.MongoClientExamples#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 {@link io.vertx.ext.mongo.MongoClient#findWithOptions}
and pass in the an instance of {@link io.vertx.ext.mongo.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`.
`hint`:: The index to use. Defaults to empty String.

=== Finding documents in batches

When dealing with large data sets, it is not advised to use the
{@link io.vertx.ext.mongo.MongoClient#find} and
{@link io.vertx.ext.mongo.MongoClient#findWithOptions} methods.
In order to avoid inflating the whole response into memory, use {@link io.vertx.ext.mongo.MongoClient#findBatch}:

[source,$lang]
----
{@link examples.MongoClientExamples#findBatch}
----

The matching documents are emitted one by one by the {@link io.vertx.core.streams.ReadStream} handler.

{@link io.vertx.ext.mongo.FindOptions} has an extra parameter `batchSize` which you can use to set the number of documents to load at once:

[source,$lang]
----
{@link examples.MongoClientExamples#findBatchWithOptions}
----

By default, `batchSize` is set to 20.

=== Finding a single document

To find a single document you use {@link io.vertx.ext.mongo.MongoClient#findOne}.

This works just like {@link io.vertx.ext.mongo.MongoClient#find} but it returns just the first matching document.

=== Removing documents

To remove documents use {@link io.vertx.ext.mongo.MongoClient#removeDocuments}.

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]
----
{@link examples.MongoClientExamples#example10}
----

=== Removing a single document

To remove a single document you use {@link io.vertx.ext.mongo.MongoClient#removeDocument}.

This works just like {@link io.vertx.ext.mongo.MongoClient#removeDocuments} but it removes just the first matching document.

=== Counting documents

To count documents use {@link io.vertx.ext.mongo.MongoClient#count}.

Here's an example that counts the number of Tolkien books. The number is passed to the result handler.

[source,$lang]
----
{@link examples.MongoClientExamples#example11}
----

=== Managing MongoDB collections

All MongoDB documents are stored in collections.

To get a list of all collections you can use {@link io.vertx.ext.mongo.MongoClient#getCollections}

[source,$lang]
----
{@link examples.MongoClientExamples#example11_1}
----

To create a new collection you can use {@link io.vertx.ext.mongo.MongoClient#createCollection}

[source,$lang]
----
{@link examples.MongoClientExamples#example11_2}
----

To drop a collection you can use {@link io.vertx.ext.mongo.MongoClient#dropCollection}

NOTE: Dropping a collection will delete all documents within it!

[source,$lang]
----
{@link examples.MongoClientExamples#example11_3}
----

=== Running other MongoDB commands

You can run arbitrary MongoDB commands with {@link io.vertx.ext.mongo.MongoClient#runCommand}.

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]
----
{@link examples.MongoClientExamples#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]
----
{@link examples.MongoClientExamples#example13_0}
----

Here's an example (in Java) of inserting a document with a binary field and reading it back

[source,$lang]
----
{@link examples.MongoClientExamples#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]
----
{@link examples.MongoClientExamples#example14_02_dl}
----
Here's an example of inserting an object ID and reading it back

[source,$lang]
----
{@link examples.MongoClientExamples#example15_dl}
----

=== Getting distinct values

Here's an example of getting distinct value

[source,$lang]
----
{@link examples.MongoClientExamples#example16}
----
Here's an example of getting distinct value in batch mode

[source,$lang]
----
{@link examples.MongoClientExamples#example16_d1}
----
* Here's an example of getting distinct value with query

[source,$lang]
----
{@link examples.MongoClientExamples#example17}
----
Here's an example of getting distinct value in batch mode with query

[source,$lang]
----
{@link examples.MongoClientExamples#example17_d1}
----

== Storing/Retrieving files and binary data

The client can store and retrieve files and binary data using MongoDB GridFS. The
{@link io.vertx.ext.mongo.MongoGridFsClient} can be used to upload or download files
and streams to GridFS.

=== Get the MongoGridFsClient to interact with GridFS.

The {@link io.vertx.ext.mongo.MongoGridFsClient} is created by calling
{@link io.vertx.ext.mongo.MongoClient#createGridFsBucketService} and providing a bucket name. In GridFS, the bucket name
ends up being a collection that contains references to all of the objects that are stored.
You can segregate objects into distinct buckets by providing a unique name.

This has the following fields:

`bucketName` : The name of the bucket to create

Here's an example of getting a {@link io.vertx.ext.mongo.MongoGridFsClient} with the a custom bucket
name

[source,$lang]
----
{@link examples.MongoClientExamples#example18}
----

GridFS uses a default bucket named "fs". If you prefer to get the default bucket instead of naming your own,
call {@link io.vertx.ext.mongo.MongoClient#createDefaultGridFsBucketService}

Here's an example of getting a {@link io.vertx.ext.mongo.MongoGridFsClient} with the default bucket name.

[source,$lang]
----
{@link examples.MongoClientExamples#example19}
----

=== Drop an entire file bucket from GridFS.

An entire file bucket along with all of its contents can be dropped with {@link io.vertx.ext.mongo.MongoGridFsClient#drop}. It will
drop the bucket that was specified when the MongoGridFsClient was created.

Here is an example of dropping a file bucket.

[source,$lang]
----
{@link examples.MongoClientExamples#example20}
----

=== Find all file IDs in a GridFS bucket.

A list of all of the file IDs in a bucket can be found with {@link io.vertx.ext.mongo.MongoGridFsClient#findAllIds}.
The files can be downloaded by ID using {@link io.vertx.ext.mongo.MongoGridFsClient#downloadFileByID}.

Here is an example of retrieving the list of file IDs.

[source,$lang]
----
{@link examples.MongoClientExamples#example21}
----

=== Find file IDs in a GridFS bucket matching a query.

A query can be specified to match files in the GridFS bucket. {@link io.vertx.ext.mongo.MongoGridFsClient#findIds}
will return a list of file IDs that match the query.

This has the following fields:

`query` : The is a json object that can match any of the file's metadata using standard MongoDB query operators. An empty
json object will match all documents. You can query on attributes of the GridFS files collection as described
in the GridFS manual. https://docs.mongodb.com/manual/core/gridfs/#the-files-collection

The files can be downloaded by ID using {@link io.vertx.ext.mongo.MongoGridFsClient#downloadFileByID}.

Here is an example of retrieving the list of file IDs based on a metadata query.

[source,$lang]
----
{@link examples.MongoClientExamples#example22}
----

=== Delete a file in GridFS based on its ID.

A file previously stored in GridFS can be deleted with {@link io.vertx.ext.mongo.MongoGridFsClient#delete} by providing
the ID of the file. The file IDs can be retrieved with a query using {@link io.vertx.ext.mongo.MongoGridFsClient#findIds}.

This has the following fields:
`id` : The ID generated by GridFS when the file was stored

Here is an example of deleting a file by ID.

[source,$lang]
----
{@link examples.MongoClientExamples#example23}
----

=== Upload a file in GridFS

A file can be stored by name with {@link io.vertx.ext.mongo.MongoGridFsClient#uploadFile}. When it
succeeds, the ID generated by GridFS will be returned. This ID can be used to retrieve the file later.

This has the following fields:

`fileName` : this is name used to save the file in GridFS

[source,$lang]
----
{@link examples.MongoClientExamples#example24}
----

=== Upload a file in GridFS with options.

A file can be stored with additional options with {@link io.vertx.ext.mongo.MongoGridFsClient#uploadFileWithOptions}
passing in an instance of {@link io.vertx.ext.mongo.GridFsUploadOptions}. When it
succeeds, the ID generated by GridFS will be returned.

This has the following fields:

`metadata` : this is a json object that includes any metadata that may be useful in a later search
`chunkSizeBytes` : GridFS will break up the file into chunks of this size

Here is an example of a file uploadByFileName that specifies the chunk size and metadata.

[source,$lang]
----
{@link examples.MongoClientExamples#example25}
----

=== Download a file previously stored in GridFS

A file can be downloaded by its original name with {@link io.vertx.ext.mongo.MongoGridFsClient#downloadFile}.
When the download is complete, the result handler will return the length of the download as a Long.

This has the following fields:

`fileName`:: the name of the file that was previously stored

Here is an example of downloading a file using the name that it was stored with in GridFS.

[source,$lang]
----
{@link examples.MongoClientExamples#example26}
----

=== Download a file previously stored in GridFS given its ID

A file can be downloaded to a given file name by its ID with {@link io.vertx.ext.mongo.MongoGridFsClient#downloadFileByID}.
 When the download succeeds, the result handler will return the length of the download as a Long.

This has the following fields:

`id` : The ID generated by GridFS when the file was stored

Here is an example of downloading a file using the ID that it was given when stored in GridFS.

[source,$lang]
----
{@link examples.MongoClientExamples#example27}
----

=== Download a file from GridFS to a new name

A file can be resolved using its original name and then downloaded to a new name
with {@link io.vertx.ext.mongo.MongoGridFsClient#downloadFileAs}.
When the download succeeds, the result handler will return the length of the download as a Long.

This has the following fields:

`fileName` : the name of the file that was previously stored
`newFileName` : the new name for which the file will be stored

[source,$lang]
----
{@link examples.MongoClientExamples#example28}
----

=== Upload a Stream to GridFS

Streams can be uploaded to GridFS using {@link io.vertx.ext.mongo.MongoGridFsClient#uploadByFileName}.
Once the stream is uploaded, the result handler will be called with the ID generated by GridFS.

This has the following fields:

`stream` : the {@link io.vertx.core.streams.ReadStream} to upload
`fileName` : the name for which the stream will be stored

Here is an example of uploading a file stream to GridFS:

[source,$lang]
----
{@link examples.MongoClientExamples#example29}
----

=== Upload a Stream to GridFS with Options

Streams can be uploaded to GridFS using {@link io.vertx.ext.mongo.MongoGridFsClient#uploadByFileNameWithOptions}
passing in an instance of {@link io.vertx.ext.mongo.GridFsUploadOptions}.
Once the stream is uploaded, the result handler will be called with the ID generated by GridFS.

This has the following fields:

`stream` : the {@link io.vertx.core.streams.ReadStream} to upload
`fileName` : the name for which the stream will be stored
`options' : the UploadOptions

{@link io.vertx.ext.mongo.GridFsUploadOptions} has the following fields:

`metadata` : this is a json object that includes any metadata that may be useful in a later search
`chunkSizeBytes` : GridFS will break up the file into chunks of this size

Here is an example of uploading a file stream with options to GridFS:

[source,$lang]
----
{@link examples.MongoClientExamples#example30}
----

=== Download a Stream from GridFS using File Name

Streams can be downloaded from GridFS using a file name with {@link io.vertx.ext.mongo.MongoGridFsClient#downloadByFileName}.
Once the stream is downloaded a result handler will be called with the length of the stream as a Long.

This has the following fields:

`stream` : the {@link io.vertx.core.streams.WriteStream} to download to
`fileName` : the name of the file that will be downloaded to the stream.

Here is an example of downloading a file to a stream:

[source,$lang]
----
{@link examples.MongoClientExamples#example31}
----

=== Download a Stream with Options from GridFS using File Name

Streams can be downloaded from GridFS using a file name and download options with
{@link io.vertx.ext.mongo.MongoGridFsClient#downloadByFileNameWithOptions} passing in an instance of {@link io.vertx.ext.mongo.GridFsDownloadOptions}.
Once the stream is downloaded a result handler will be called with the length of the stream as a Long.

This has the following fields:

`stream` : the {@link io.vertx.core.streams.WriteStream} to download to
`fileName` : the name of the file that will be downloaded to the stream
`options` : an instance of {@link io.vertx.ext.mongo.GridFsDownloadOptions}

DownloadOptions has the following field:

`revision` : the revision of the file to download

Here is an example of downloading a file to a stream with options:

[source,$lang]
----
{@link examples.MongoClientExamples#example32}
----

=== Download a Stream from GridFS using ID

Streams can be downloaded using the ID generated by GridFS with {@link io.vertx.ext.mongo.MongoGridFsClient#downloadById}.
Once the stream is downloaded a result handler will be called with the length of the stream as a Long.

This has the following fields:

`stream` : the {@link io.vertx.core.streams.WriteStream} to download to
`id` : the string represendation of the ID generated by GridFS

Here is an example of downloading a file to a stream using the object's ID:

[source,$lang]
----
{@link examples.MongoClientExamples#example33}
----

== 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.

`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
  "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

  // Server Settings
  "heartbeatFrequencyMS"    : 1000, // long
  "minHeartbeatFrequencyMS" :  500, // long

  // SSL Settings
  "ssl" : false,                       // boolean
  "sslInvalidHostNameAllowed" : false, // boolean
  "trustAll" : false,                  // boolean
  "keyPath" : "key.pem",               // string
  "certPath" : "cert.pem",             // string
  "caPath" : "ca.pem"                  // string
}
----

*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
`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.
`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)
`ssl`:: Enable ssl between the vertx-mongo-client and mongo
`sslInvalidHostNameAllowed`:: Accept hostnames not included in the servers certificate
`trustAll`:: When using ssl, trust _ALL_ certificates. *WARNING* - Trusting _ALL_ certificates will open you up to potential security issues such as MITM attacks.
`keyPath`:: Set a path to a file that contains the client key that will be used to authenticate against the server when making SSL connections to mongo.
`certPath`:: Set a path to a file that contains the certificate that will be used to authenticate against the server when making SSL connections to mongo.
`caPath`:: Set a path to a file that contains a certificate that will be used as a source of trust when making SSL connections to mongo.


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.

ifeval::["$lang" == "java"]
include::override/rxjava3.adoc[]
endif::[]
