Struct Builder 

pub struct Builder<M: Manager> { /* private fields */ }

Available on crate feature std only.

A fluent builder for a Pool.

Created by Pool::builder. Each setter consumes and returns the builder, so calls chain; build validates the configuration and pre-creates the min_idle resources.

Examples

use std::time::Duration;
use pool_mod::{Manager, Pool};
use std::convert::Infallible;
let pool = Pool::builder(M)
    .max_size(32)
    .min_idle(4)
    .idle_timeout(Some(Duration::from_secs(600)))
    .max_lifetime(Some(Duration::from_secs(3600)))
    .build()
    .expect("configuration is valid");
assert_eq!(pool.status().idle, 4);

Implementations

impl<M: Manager> Builder<M>

pub fn new(manager: M) -> Self

Create a builder for manager seeded with the default configuration.

pub fn max_size(self, max_size: usize) -> Self

Set the maximum number of resources the pool may own at once.

pub fn min_idle(self, min_idle: usize) -> Self

Set how many resources to create up front and keep ready.

pub fn create_timeout(self, timeout: Option<Duration>) -> Self

Set how long Pool::get waits when the pool is saturated. None waits indefinitely.

pub fn idle_timeout(self, timeout: Option<Duration>) -> Self

Set the idle-expiry window. None disables idle expiry.

pub fn max_lifetime(self, lifetime: Option<Duration>) -> Self

Set the maximum resource lifetime. None disables lifetime expiry.

pub fn config(self, config: PoolConfig) -> Self

Replace the entire configuration with config.

Useful when the configuration is loaded from a file rather than assembled setter by setter.

pub fn build(self) -> Result<Pool<M>, Error<M::Error>>

Validate the configuration, build the pool, and pre-create min_idle resources.

Errors

• Error::InvalidConfig if max_size is zero or min_idle exceeds max_size.
• Error::Backend if creating one of the min_idle resources fails; any already-created resources are dropped before returning.

Examples

use pool_mod::{Error, Manager, Pool};
use std::convert::Infallible;
let invalid = Pool::builder(M).max_size(0).build();
assert!(matches!(invalid, Err(Error::InvalidConfig(_))));