In writing my tests, I'd like to be able to inject a connection into the request so that I can wrap the entire test case in a transaction (even if there is more than one request in the test case).
I've attempted to do this using a BeforeMiddleware which I can link in my test cases to insert a connection, as such:
pub type DatabaseConnection = PooledConnection<ConnectionManager<PgConnection>>;pub struct DatabaseOverride { conn: DatabaseConnection,}impl BeforeMiddleware for DatabaseOverride { fn before(&self, req: &mut Request) -> IronResult<()> { req.extensions_mut().entry::<DatabaseOverride>().or_insert(self.conn); Ok(()) }}However, I'm encountering a compile error in trying to do this:
error: the trait bound `std::rc::Rc<diesel::pg::connection::raw::RawConnection>: std::marker::Sync` is not satisfied [E0277]impl BeforeMiddleware for DatabaseOverride { ^~~~~~~~~~~~~~~~help: run `rustc --explain E0277` to see a detailed explanationnote: `std::rc::Rc<diesel::pg::connection::raw::RawConnection>` cannot be shared between threads safelynote: required because it appears within the type `diesel::pg::PgConnection`note: required because it appears within the type `r2d2::Conn<diesel::pg::PgConnection>`note: required because it appears within the type `std::option::Option<r2d2::Conn<diesel::pg::PgConnection>>`note: required because it appears within the type `r2d2::PooledConnection<r2d2_diesel::ConnectionManager<diesel::pg::PgConnection>>`note: required because it appears within the type `utility::db::DatabaseOverride`note: required by `iron::BeforeMiddleware`error: the trait bound `std::cell::Cell<i32>: std::marker::Sync` is not satisfied [E0277]impl BeforeMiddleware for DatabaseOverride { ^~~~~~~~~~~~~~~~help: run `rustc --explain E0277` to see a detailed explanationnote: `std::cell::Cell<i32>` cannot be shared between threads safelynote: required because it appears within the type `diesel::pg::PgConnection`note: required because it appears within the type `r2d2::Conn<diesel::pg::PgConnection>`note: required because it appears within the type `std::option::Option<r2d2::Conn<diesel::pg::PgConnection>>`note: required because it appears within the type `r2d2::PooledConnection<r2d2_diesel::ConnectionManager<diesel::pg::PgConnection>>`note: required because it appears within the type `utility::db::DatabaseOverride`note: required by `iron::BeforeMiddleware`Is there a way around this with diesel's connections? I've found several examples on Github to do this using the pg crate, but I'd like to keep using diesel.