Module Multispool.Make

Parameters

Signature

type t
val sexp_of_t : t -> Ppx_sexp_conv_lib.Sexp.t
type spool = t
module Spoolable : Async_smtp__.Multispool_intf.Spoolable.S
val dir : t -> string
val load : ?⁠create_if_missing:unit -> string -> t Async.Deferred.Or_error.t

Open a Multispool.t. This function will fail by default if the spool directory does not exist, does not look like a spool, or does not contain the set of directories named after the strings returned by Spoolable.Queue.to_dir. Pass ~create_if_missing:() to create the necessary directories.

Note that, even if ~create_if_missing:() is specified, this function will still fail if the supplied directory is non-empty and not already a spool.

val load_unsafe : string -> t

Open a Multispool.t with no spool directory validation.

val create : string -> t Async.Deferred.Or_error.t

Open a Multispool.t and create the spool directory if necessary. This is functionally identical to load ?create_if_missing:().

module Data_file : sig ... end

Provide access to a Spoolable.Data.t. Data_file.t functions as a "handle" to the underlying data so the user can choose when to read a Spoolable.Data.t.

module Entry : sig ... end

An Entry is associated with a particular queue

val list : t -> Spoolable.Queue.t -> Entry.t list Async.Deferred.Or_error.t
module Unique_name : sig ... end
val enqueue : t -> Spoolable.Queue.t -> Spoolable.Metadata.t -> Spoolable.Data.t -> [ `Reserve of Spoolable.Name_generator.t | `Use of Spoolable.Name_generator.Unique_name.t ] -> Entry.t Async.Deferred.Or_error.t

Add a Spoolable to a queue. An Entry.t is returned, but it may make sense to ignore it.

val with_entry : f:(Spoolable.Metadata.t -> Data_file.t -> ([ `Save of Spoolable.Metadata.t * Spoolable.Queue.t | `Remove ] * 'a) Async.Deferred.t) -> Entry.t -> 'a Async.Deferred.Or_error.t

Do something with the contents of an entry within f. Use with_entry if you expect to be the only user of an Entry.t and it is an error if the Entry.t is grabbed by another process (or otherwise disappears). See checkout for a lower-level interface.

val with_entry' : f:(Spoolable.Metadata.t -> Data_file.t -> ([ `Save of Spoolable.Metadata.t * Spoolable.Queue.t | `Remove ] * 'a) Async.Deferred.t) -> Entry.t -> [ `Ok of 'a | `Not_found ] Async.Deferred.Or_error.t

Like with_entry, but use with_entry' if you expect that another process might race to grab an Entry.t and want straightforward handling. See checkout' for a lower-level interface.

module Queue_reader : sig ... end

Interface for iteration and waiting on queue activity. Multiple processes will not interfere with one another.

module Expert : sig ... end