Trait Executor 

pub trait Executor:
    Any
    + Send
    + Sync
    + 'static {
    // Required method
    fn as_any(&self) -> &dyn Any;

    // Provided method
    fn non_transactional(&self) -> Option<Arc<dyn Executor>> { ... }
}

An ambient handle to a unit of database work, installed in the task-local for the lifetime of a request or a worker job.

The trait is object-safe so the engine can carry it as Arc<dyn Executor> without naming a concrete ORM. The concrete handle (a SeaORM Executor enum, a sqlx::Pool, a diesel_async::Connection, …) implements this trait; an ORM-specific Repo recovers the concrete type via Executor::as_any when it needs to issue a query.

Downcasting is the documented seam: this crate stays free of every candidate ORM’s query API, and each Repo knows exactly which executor shape its Module installs. A downcast miss is a framework bug (mismatched Module + Repo); the contract is log at error and degrade to None — the Repo then fails the operation (no ambient executor), so the request errors loudly instead of panicking a worker thread or silently reading “no rows”.

Required Methods

fn as_any(&self) -> &dyn Any

Downcast handle. Used by an ORM-specific Repo to recover its concrete executor type from the ambient Arc<dyn Executor>.

Provided Methods

fn non_transactional(&self) -> Option<Arc<dyn Executor>>

A handle on the same database outside this executor’s transaction, or None when there is nothing to step out of (already a pool) or the ORM cannot produce one.

A transport that has proven an operation cannot write installs this for the operation’s duration, so the work runs without opening — and without pinning a connection to — the request transaction. The one caller today is the GraphQL endpoint: every operation arrives as a POST, so the HTTP boundary hands even a pure query a transaction it will never need.

Only ever pass work that cannot write. A mutation on the returned handle loses atomicity and rollback. The default None is therefore the fail-closed answer: an ORM that ignores this keeps the request executor it was given.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors