happy-eyeballs 0.3.1 · OCaml Package

type t

The internal state of happy eyeballs.

type action =

| Resolve_a of [ `host ] Domain_name.t
| Resolve_aaaa of [ `host ] Domain_name.t
| Connect of [ `host ] Domain_name.t * int * Ipaddr.t * int
| Connect_failed of [ `host ] Domain_name.t * int

The variant of actions to be performed by the effectful layer.

val pp_action : action Fmt.t

pp_action ppf a pretty-prints the action a on ppf.

type event =

| Resolved_a of [ `host ] Domain_name.t * Ipaddr.V4.Set.t
| Resolved_aaaa of [ `host ] Domain_name.t * Ipaddr.V6.Set.t
| Resolved_a_failed of [ `host ] Domain_name.t
| Resolved_aaaa_failed of [ `host ] Domain_name.t
| Connection_failed of [ `host ] Domain_name.t * int * Ipaddr.t * int
| Connected of [ `host ] Domain_name.t * int * Ipaddr.t * int

The variant of events.

val pp_event : event Fmt.t

pp_event ppf e pretty-prints event e on ppf.

val create : 
  ?aaaa_timeout:int64 ->
  ?v6_connect_timeout:int64 ->
  ?connect_timeout:int64 ->
  ?resolve_timeout:int64 ->
  ?resolve_retries:int ->
  int64 ->
  t

create ~aaaa_timeout ~v6_connect_timeout ~connect_timeout ~resolve_timeout ~resolve_retries ts creates the internal state, initialized with the timestamp ts (an arbitrary number that must be monotonically increasing). The timeouts are specified in nanoseconds: the default of aaaa_timeout is Duration.of_ms 50, v6_connect_timeout is Duration.of_ms 200, connect_timeout is Duration.of_sec 10, and resolve_timeout is Duration.of_sec 1. The resolve_retries defaults to 3.

val timer : t -> int64 -> t * [ `Suspend | `Act ] * action list

timer t ts is a timer function that results in an updated t and either `Suspend signalling that there are no pending connection establishments and the timer thread can suspend, or `Act that the timer should be called again after sleeping. In addition, a list of actions that need to be performed (connection establishment to be retried, connection failures to be reported, ...) is provided. If the timer thread has been suspended it should be signalled to resume after calling connect or connect_ip.

val connect : 
  t ->
  int64 ->
  id:int ->
  [ `host ] Domain_name.t ->
  int list ->
  t * action list

connect t ts ~id host ports attempts a connection to host, where the ports are attempted in sequence. It results in an updated t and a list of actions to be performed.

raises Failure
if ports is the empty list.

val connect_ip : 
  t ->
  int64 ->
  id:int ->
  (Ipaddr.t * int) list ->
  t * action list

connect_ip t ts ~id addresses attempts a connection to addresses. By default, the list will be tried in sequence. The ports will be tried in sequence. The result is an updated t and a list of actions to be performed.

raises Failure
if addresses is the empty list.

val event : t -> int64 -> event -> t * action list

event t ts ev results in an updated t and a list of actions to be performed.

raises Failure
if ev contains an empty set of IP addresses.

module Waiter_map : sig ... end

A map for waiters and internal id.

package happy-eyeballs