A generic connection pool for Rust
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Latest commit f56a081 Jul 18, 2018

README.md

r2d2

CircleCI

A generic connection pool for Rust.

Documentation

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
mongodb r2d2-mongodb
odbc r2d2-odbc

Example

Using an imaginary "foodb" database.

use std::thread;

extern crate r2d2;
extern crate r2d2_foodb;

fn main() {
    let manager = r2d2_foodb::FooConnectionManager::new("localhost:1234");
    let pool = r2d2::Pool::builder()
        .max_size(15)
        .build(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.
        })
    }
}

License

Licensed under either of

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you shall be dual licensed as above, without any additional terms or conditions.