Struct MongoBackend 

pub struct MongoBackend { /* private fields */ }

MongoDB adapter: compiles plans to filters and pipelines and runs them.

Collections are named after tables. The primary-key column of a collection is stored as _id (see Keys); rows come back with _id renamed to that column. Integer keys that a plan does not supply are generated from a counter collection, siderite_counters.

Implementations

impl MongoBackend

pub async fn connect(url: &str, database: &str) -> Result<Self, BackendError>

Connect to url and use database database.

Errors

BackendError::Connection if the URL is invalid or no server can be reached.

pub fn from_client(client: Client, database: &str) -> Self

Use an existing client.

pub fn with_keys(self, keys: Keys) -> Self

Set which column of each collection is stored as _id (default: a column named id).

pub fn database(&self) -> &Database

The database this adapter works in.

pub async fn raw_command(&self, command: Document) -> Result<Document, OrmError>

Run a database command (db.runCommand), the escape hatch for what plans cannot express.

Errors

BackendError when the server rejects the command.

pub async fn create_unique_index( &self, collection: &str, column: &str, ) -> Result<(), OrmError>

Create a unique index on column of collection, so duplicate values fail with BackendError::Constraint like a SQL unique constraint. MongoDB enforces uniqueness only for _id otherwise.

Errors

BackendError when the index cannot be created.

Trait Implementations

impl Backend for MongoBackend

fn begin<'life0, 'async_trait>( &'life0 self, isolation: Option<IsolationLevel>, ) -> Pin<Box<dyn Future<Output = Result<Box<dyn Transaction>, OrmError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Begin a transaction on a dedicated connection.

fn read_parameter_count( &self, _plan: &QueryPlan, ) -> Result<Option<usize>, OrmError>

Count compiled read parameters without database I/O.

fn begin_schema<'life0, 'async_trait>( &'life0 self, transactional: bool, ) -> Pin<Box<dyn Future<Output = Result<Box<dyn Transaction>, OrmError>> + Send + 'async_trait>>

where 'life0: 'async_trait, Self: Sync + 'async_trait,

Connection for a schema migration.

impl Clone for MongoBackend

fn clone(&self) -> MongoBackend

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MongoBackend

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Executor for MongoBackend

fn capabilities(&self) -> BackendCapabilities

Declared capabilities.

fn fetch<'life0, 'life1, 'async_trait>( &'life0 self, plan: &'life1 QueryPlan, ) -> Pin<Box<dyn Future<Output = Result<QueryResult, OrmError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Execute a read plan.

fn execute<'life0, 'life1, 'async_trait>( &'life0 self, plan: &'life1 WritePlan, ) -> Pin<Box<dyn Future<Output = Result<ExecResult, OrmError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Execute a write plan.

fn fetch_raw<'life0, 'life1, 'async_trait>( &'life0 self, _sql: &'life1 str, _params: Vec<Value>, ) -> Pin<Box<dyn Future<Output = Result<QueryResult, OrmError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Run raw SQL returning rows. params are bound, never interpolated.

fn execute_raw<'life0, 'life1, 'async_trait>( &'life0 self, _sql: &'life1 str, _params: Vec<Value>, ) -> Pin<Box<dyn Future<Output = Result<u64, OrmError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Run raw SQL returning the affected-row count. params are bound.

fn execute_script<'life0, 'life1, 'async_trait>( &'life0 self, _sql: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<(), OrmError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Run a multi-statement script without parameters (DDL, migrations).