package caqti

  1. Overview
  2. Docs

The signature of pools of reusable resources. We use it to keep pools of open database connections. A generic implementation is found in Caqti_pool which is used to provide connect_pool functions.

This interface is based on Lwt_pool.

type 'a io
type 'a t
val create : ?max_size:int -> ?check:('a -> (bool -> unit) -> unit) -> ?validate:('a -> bool io) -> (unit -> 'a io) -> ('a -> unit io) -> 'a t

(internal) create alloc free is a pool of resources allocated by alloc and freed by free. This is primarily indented for implementing the connect_pool functions.

  • parameter max_size

    Maximum number of resources to allocate at any given time.

  • parameter check

    A function used to check a resource after use.

  • parameter validate

    A function to check before use that a resource is still valid.

val size : 'a t -> int

size pool is the current number of open resources in pool.

val use : ?priority:float -> ('a -> 'b io) -> 'a t -> 'b io

use f pool calls f on a resource drawn from pool, handing back the resource to the pool when f exits.

  • parameter priority

    Requests for the resource are handled in decreasing order of priority. The default priority is 0.0.

val drain : 'a t -> unit io

drain pool closes all resources in pool. The pool is still usable, as new resources will be created on demand.


Innovation. Community. Security.