Struct ClientGuard

struct ClientGuard {
    _tx: Sender<()>,
    client: Client,
}

An async-drop style Guard for mongodb::Client. Use this guard to hold a client, the client::shutdown is called in an async manner when the guard is dropped. Please be aware this is a “best effort” style shutdown, which may not be successful if the tokio runtime is in the process of terminating. However, the server-side resources will be cleaned up eventually due to the session expiration. see this issue for more information

Fields

_tx: Sender<()>

client: Client

Implementations

impl ClientGuard

fn new(name: String, client: Client) -> Self

Methods from Deref<Target = Client>

pub fn selection_criteria(&self) -> Option<&SelectionCriteria>

Gets the default selection criteria the Client uses for operations..

pub fn read_concern(&self) -> Option<&ReadConcern>

Gets the default read concern the Client uses for operations.

pub fn write_concern(&self) -> Option<&WriteConcern>

Gets the default write concern the Client uses for operations.

pub fn database(&self, name: &str) -> Database

Gets a handle to a database specified by name in the cluster the Client is connected to. The Database options (e.g. read preference and write concern) will default to those of the Client.

This method does not send or receive anything across the wire to the database, so it can be used repeatedly without incurring any costs from I/O.

pub fn database_with_options( &self, name: &str, options: DatabaseOptions, ) -> Database

Gets a handle to a database specified by name in the cluster the Client is connected to. Operations done with this Database will use the options specified by options by default and will otherwise default to those of the Client.

This method does not send or receive anything across the wire to the database, so it can be used repeatedly without incurring any costs from I/O.

pub fn default_database(&self) -> Option<Database>

Gets a handle to the default database specified in the ClientOptions or MongoDB connection string used to construct this Client.

If no default database was specified, None will be returned.

pub async fn list_databases( &self, filter: impl Into<Option<Document>>, options: impl Into<Option<ListDatabasesOptions>>, ) -> Result<Vec<DatabaseSpecification>, Error>

Gets information about each database present in the cluster the Client is connected to.

pub async fn list_databases_with_session( &self, filter: impl Into<Option<Document>>, options: impl Into<Option<ListDatabasesOptions>>, session: &mut ClientSession, ) -> Result<Vec<DatabaseSpecification>, Error>

Gets information about each database present in the cluster the Client is connected to using the provided ClientSession.

pub async fn list_database_names( &self, filter: impl Into<Option<Document>>, options: impl Into<Option<ListDatabasesOptions>>, ) -> Result<Vec<String>, Error>

Gets the names of the databases present in the cluster the Client is connected to.

pub async fn start_session( &self, options: impl Into<Option<SessionOptions>>, ) -> Result<ClientSession, Error>

Starts a new ClientSession.

pub async fn watch( &self, pipeline: impl IntoIterator<Item = Document>, options: impl Into<Option<ChangeStreamOptions>>, ) -> Result<ChangeStream<ChangeStreamEvent<Document>>, Error>

Starts a new ChangeStream that receives events for all changes in the cluster. The stream does not observe changes from system collections or the “config”, “local” or “admin” databases. Note that this method (watch on a cluster) is only supported in MongoDB 4.0 or greater.

See the documentation here on change streams.

Change streams require either a “majority” read concern or no read concern. Anything else will cause a server error.

Note that using a $project stage to remove any of the _id operationType or ns fields will cause an error. The driver requires these fields to support resumability. For more information on resumability, see the documentation for ChangeStream

If the pipeline alters the structure of the returned events, the parsed type will need to be changed via ChangeStream::with_type.

pub async fn watch_with_session( &self, pipeline: impl IntoIterator<Item = Document>, options: impl Into<Option<ChangeStreamOptions>>, session: &mut ClientSession, ) -> Result<SessionChangeStream<ChangeStreamEvent<Document>>, Error>

Starts a new SessionChangeStream that receives events for all changes in the cluster using the provided ClientSession. See Client::watch for more information.

pub async fn warm_connection_pool(&self)

Add connections to the connection pool up to min_pool_size. This is normally not needed - the connection pool will be filled in the background, and new connections created as needed up to max_pool_size. However, it can sometimes be preferable to pay the (larger) cost of creating new connections up-front so that individual operations execute as quickly as possible.

Note that topology changes require rebuilding the connection pool, so this method cannot guarantee that the pool will always be filled for the lifetime of the Client.

Does nothing if min_pool_size is unset or zero.

Trait Implementations

impl Deref for ClientGuard

type Target = Client

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.