A generic connection pool for Rust.
Opening a new database connection every time one is needed is both inefficient and can lead to resource exhaustion under high traffic conditions. A connection pool maintains a set of open connections to a database, handing them out for repeated use.
r2d2 is agnostic to the connection type it is managing. Implementors of the
ManageConnection
trait provide the database-specific logic to create and
check the health of connections.
A (possibly not exhaustive) list of adaptors for different backends:
Backend | Adaptor Crate ------------------------------------------------------------------- | ------------- rust-postgres | r2d2-postgres redis-rs | r2d2-redis rust-mysql-simple | r2d2-mysql rusqlite | r2d2-sqlite rusted-cypher | r2d2-cypher diesel | r2d2-diesel couchdb | r2d2-couchdb
Using an imaginary "foodb" database. ```rust use std::thread;
extern crate r2d2; extern crate r2d2_foodb;
fn main() { let config = r2d2::Config::builder() .poolsize(15) .build(); let manager = r2d2foodb::FooConnectionManager::new("localhost:1234");
let pool = r2d2::Pool::new(config, manager).unwrap();
for _ in 0..20 {
let pool = pool.clone();
thread::spawn(move || {
let conn = pool.get().unwrap();
// use the connection
// it will be returned to the pool when it falls out of scope.
})
}
} ```
Licensed under either of * Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0) * MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
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