Source file gossipsub_worker.ml
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module Make (C : Gossipsub_intf.WORKER_CONFIGURATION) :
Gossipsub_intf.WORKER
with module GS = C.GS
and module Monad = C.Monad
and module Stream = C.Stream
and module Point = C.Point = struct
module GS = C.GS
module Monad = C.Monad
module Stream = C.Stream
module View = GS.Introspection
module Topic = GS.Topic
module Peer = GS.Peer
module Message_id = GS.Message_id
module Message = GS.Message
module Point = C.Point
module Introspection = struct
type stats = {
mutable count_topics : int64;
mutable count_connections : int64;
mutable count_bootstrap_connections : int64;
mutable count_sent_app_messages : int64;
mutable count_sent_grafts : int64;
mutable count_sent_prunes : int64;
mutable count_sent_ihaves : int64;
mutable count_sent_iwants : int64;
mutable count_recv_valid_app_messages : int64;
mutable count_recv_invalid_app_messages : int64;
mutable count_recv_unknown_validity_app_messages : int64;
mutable count_recv_grafts : int64;
mutable count_recv_prunes : int64;
mutable count_recv_ihaves : int64;
mutable count_recv_iwants : int64;
}
let empty_stats () =
{
count_topics = 0L;
count_connections = 0L;
count_bootstrap_connections = 0L;
count_sent_app_messages = 0L;
count_sent_grafts = 0L;
count_sent_prunes = 0L;
count_sent_ihaves = 0L;
count_sent_iwants = 0L;
count_recv_valid_app_messages = 0L;
count_recv_invalid_app_messages = 0L;
count_recv_unknown_validity_app_messages = 0L;
count_recv_grafts = 0L;
count_recv_prunes = 0L;
count_recv_ihaves = 0L;
count_recv_iwants = 0L;
}
let counter_update = function
| `Incr -> 1L
| `Decr -> -1L
| `Plus n -> Int64.of_int n
| `Minus n -> Int64.of_int (-n)
let ( ++ ) = Int64.add
let update_count_topics t delta =
t.count_topics <- t.count_topics ++ counter_update delta
let update_count_connections t delta =
t.count_connections <- t.count_connections ++ counter_update delta
let update_count_bootstrap_connections t delta =
t.count_bootstrap_connections <-
t.count_bootstrap_connections ++ counter_update delta
let update_count_recv_grafts t delta =
t.count_recv_grafts <- t.count_recv_grafts ++ counter_update delta
let update_count_recv_prunes t delta =
t.count_recv_prunes <- t.count_recv_prunes ++ counter_update delta
let update_count_recv_ihaves t delta =
t.count_recv_ihaves <- t.count_recv_ihaves ++ counter_update delta
let update_count_recv_iwants t delta =
t.count_recv_iwants <- t.count_recv_iwants ++ counter_update delta
let update_count_recv_invalid_app_messages t delta =
t.count_recv_invalid_app_messages <-
t.count_recv_invalid_app_messages ++ counter_update delta
let update_count_recv_unknown_validity_app_messages t delta =
t.count_recv_unknown_validity_app_messages <-
t.count_recv_unknown_validity_app_messages ++ counter_update delta
let update_count_recv_valid_app_messages t delta =
t.count_recv_valid_app_messages <-
t.count_recv_valid_app_messages ++ counter_update delta
let update_count_sent_grafts t delta =
t.count_sent_grafts <- t.count_sent_grafts ++ counter_update delta
let update_count_sent_prunes t delta =
t.count_sent_prunes <- t.count_sent_prunes ++ counter_update delta
let update_count_sent_ihaves t delta =
t.count_sent_ihaves <- t.count_sent_ihaves ++ counter_update delta
let update_count_sent_iwants t delta =
t.count_sent_iwants <- t.count_sent_iwants ++ counter_update delta
let update_count_sent_app_messages t delta =
t.count_sent_app_messages <-
t.count_sent_app_messages ++ counter_update delta
end
type 'a cancellation_handle = {
schedule_cancellation : unit -> 'a Monad.t;
(** A handle for a cancellable looping monad. When
[schedule_cancellation ()] is called, the internal monad is
returned. Details on how the returned monad resovles or is cancelled
depends on the loop's implementation. *)
}
(** A worker has one of the following statuses:
- [Starting] in case it is initialized with {!make} but not started yet.
- [Running] in case the function [start] has been called. *)
type worker_status =
| Starting
| Running of {
heartbeat_handle : unit cancellation_handle;
event_loop_handle : unit cancellation_handle;
}
type p2p_message =
| Graft of {topic : Topic.t}
| Prune of {topic : Topic.t; px : Peer.t Seq.t; backoff : GS.Span.t}
| IHave of {topic : Topic.t; message_ids : Message_id.t list}
| IWant of {message_ids : Message_id.t list}
| Subscribe of {topic : Topic.t}
| Unsubscribe of {topic : Topic.t}
type p2p_input =
| In_message of {from_peer : Peer.t; p2p_message : p2p_message}
| New_connection of {
peer : Peer.t;
direct : bool;
trusted : bool;
bootstrap : bool;
}
| Disconnection of {peer : Peer.t}
type app_input =
| Publish_message of message_with_header
| Join of Topic.t
| Leave of Topic.t
type peer_origin = PX of Peer.t | Trusted
type p2p_output =
| Out_message of {to_peer : Peer.t; p2p_message : p2p_message}
| Disconnect of {peer : Peer.t}
| Kick of {peer : Peer.t}
| Connect of {peer : Peer.t; origin : peer_origin}
| Connect_point of {point : Point.t}
| Forget of {peer : Peer.t; origin : Peer.t}
type app_output = message_with_header
(** The different kinds of events the Gossipsub worker handles. *)
type event = Heartbeat | P2P_input of p2p_input | App_input of app_input
(** The worker's state is made of the gossipsub automaton's state,
and a stream of events to process. It also has two output streams to
communicate with the application and P2P layers. *)
type worker_state = {
stats : Introspection.stats;
gossip_state : GS.state;
bootstrap_points : Point.Set.t;
trusted_peers : Peer.Set.t;
connected_bootstrap_peers : Peer.Set.t;
events_stream : event Stream.t;
p2p_output_stream : p2p_output Stream.t;
app_output_stream : app_output Stream.t;
events_logging : event -> unit Monad.t;
}
(** A worker instance is made of its status and state. *)
type t = {mutable status : worker_status; mutable state : worker_state}
let state {state; _} = GS.Introspection.view state.gossip_state
let emit_app_output state e = Stream.push e state.app_output_stream
let emit_p2p_output =
let update_sent_stats stats = function
| Out_message {p2p_message; to_peer = _} -> (
match p2p_message with
| Graft _ -> Introspection.update_count_sent_grafts stats `Incr
| Prune _ -> Introspection.update_count_sent_prunes stats `Incr
| IHave _ -> Introspection.update_count_sent_ihaves stats `Incr
| IWant _ -> Introspection.update_count_sent_iwants stats `Incr
| Message_with_header _ ->
Introspection.update_count_sent_app_messages stats `Incr
| Subscribe _ | Unsubscribe _ -> ())
| Connect _ | Connect_point _ | Disconnect _ | Forget _ | Kick _ -> ()
in
fun {connected_bootstrap_peers; p2p_output_stream; stats; _} ~mk_output ->
let maybe_emit to_peer =
let message = mk_output to_peer in
let do_emit =
(not (Peer.Set.mem to_peer connected_bootstrap_peers))
||
match message with
| Out_message {p2p_message; to_peer = _} -> (
match p2p_message with
| Message_with_header _ | IHave _ | IWant _ ->
false
| Graft _ | Prune _ | Subscribe _ | Unsubscribe _ -> true)
| Connect _ | Connect_point _ | Disconnect _ | Forget _ | Kick _ ->
true
in
if do_emit then (
update_sent_stats stats message ;
Stream.push message p2p_output_stream)
in
Seq.iter maybe_emit
let emit_p2p_message state p2p_message =
emit_p2p_output state ~mk_output:(fun to_peer ->
Out_message {to_peer; p2p_message})
(** From the worker's perspective, handling publishing a message consists in:
- Sending it to peers returned in [to_publish] field of
[GS.Publish_message] output);
Note that it's the responsability of the automaton modules to filter out
peers based on various criteria (bad score, connection expired, ...). *)
let handle_publish_message publish_message = function
| state, GS.Publish_message {to_publish} ->
let ({topic; message_id; message} : GS.publish_message) =
publish_message
in
let = {message; topic; message_id} in
let p2p_message = Message_with_header message_with_header in
emit_p2p_message state p2p_message (Peer.Set.to_seq to_publish) ;
state
| state, GS.Already_published -> state
(** From the worker's perspective, handling receiving a message consists in:
- Sending it to peers returned in [to_route] field of
[GS.Route_message] output);
- Notifying the application layer if it is interesed in it.
Note that it's the responsability of the automaton modules to filter out
peers based on various criteria (bad score, connection expired, ...). *)
let handle_receive_message received_message = function
| state, GS.Route_message {to_route} ->
Introspection.update_count_recv_valid_app_messages state.stats `Incr ;
let ({sender = _; topic; message_id; message} : GS.receive_message) =
received_message
in
let = {message; topic; message_id} in
let p2p_message = Message_with_header message_with_header in
emit_p2p_message state p2p_message (Peer.Set.to_seq to_route) ;
let has_joined = View.(has_joined topic @@ view state.gossip_state) in
if has_joined then emit_app_output state message_with_header ;
state
| state, GS.Already_received | state, GS.Not_subscribed -> state
| state, GS.Unknown_validity ->
Introspection.update_count_recv_unknown_validity_app_messages
state.stats
`Incr ;
state
| state, GS.Invalid_message ->
Introspection.update_count_recv_invalid_app_messages state.stats `Incr ;
state
(** From the worker's perspective, the outcome of joining a new topic from the
application layer are:
- Sending [Subscribe] messages to connected peers with that topic;
- Sending [Graft] messages to the newly construced topic's mesh. *)
let handle_join topic = function
| state, GS.Already_joined -> state
| state, Joining_topic {to_graft} ->
Introspection.update_count_topics state.stats `Incr ;
let peers = View.(view state.gossip_state |> get_connected_peers) in
emit_p2p_message state (Subscribe {topic}) (List.to_seq peers) ;
emit_p2p_message state (Graft {topic}) (Peer.Set.to_seq to_graft) ;
state
(** From the worker's perspective, the outcome of leaving a topic by the
application layer are:
- Sending [Prune] messages to the topic's mesh;
- Sending [Unsubscribe] messages to connected peers. *)
let handle_leave topic = function
| state, GS.Not_joined -> state
| state, Leaving_topic {to_prune; noPX_peers} ->
Introspection.update_count_topics state.stats `Decr ;
let gstate = state.gossip_state in
let view = View.view gstate in
let peers = View.get_connected_peers view in
let backoff = (View.limits view).unsubscribe_backoff in
Peer.Set.iter
(fun peer_to_prune ->
let prune =
let px =
GS.select_px_peers gstate ~peer_to_prune topic ~noPX_peers
|> List.to_seq
in
Prune {topic; px; backoff}
in
emit_p2p_message state prune (Seq.return peer_to_prune))
to_prune ;
emit_p2p_message state (Unsubscribe {topic}) (List.to_seq peers) ;
state
(** When a new peer is connected, the worker will send a [Subscribe] message
to that peer for each topic the local peer tracks. *)
let handle_new_connection peer ~bootstrap ~trusted = function
| state, GS.Peer_already_known -> state
| state, Peer_added ->
Introspection.update_count_connections state.stats `Incr ;
let connected_bootstrap_peers =
if bootstrap then (
Introspection.update_count_bootstrap_connections state.stats `Incr ;
Peer.Set.add peer state.connected_bootstrap_peers)
else state.connected_bootstrap_peers
in
let trusted_peers =
if trusted then Peer.Set.add peer state.trusted_peers
else state.trusted_peers
in
let state = {state with connected_bootstrap_peers; trusted_peers} in
View.(view state.gossip_state |> get_our_topics)
|> List.iter (fun topic ->
emit_p2p_message state (Subscribe {topic}) (Seq.return peer)) ;
state
(** When a peer is disconnected, the worker has nothing to do, as:
- It cannot send [Prune] or [Unsubscribe] to the remote peer because the
connection is closed;
- [Prune] or [Unsubscribe] are already handled when calling
{!GS.remove_peer}. *)
let handle_disconnection peer = function
| state, GS.Removing_peer ->
Introspection.update_count_connections state.stats `Decr ;
if Peer.Set.mem peer state.connected_bootstrap_peers then
Introspection.update_count_bootstrap_connections state.stats `Decr ;
{
state with
connected_bootstrap_peers =
Peer.Set.remove peer state.connected_bootstrap_peers;
}
(** When a [Graft] request from a remote peer is received, the worker forwards
it to the automaton. In certain cases the peer needs to be pruned. Other
than that there is nothing else to do. *)
let handle_graft peer topic (state, output) =
let gstate = state.gossip_state in
let backoff = View.(view gstate |> limits).prune_backoff in
let do_prune ~do_px =
let prune =
let px =
if do_px then
GS.select_px_peers
gstate
~peer_to_prune:peer
topic
~noPX_peers:Peer.Set.empty
|> List.to_seq
else Seq.empty
in
Prune {topic; px; backoff}
in
emit_p2p_message state prune (Seq.return peer)
in
let () =
match output with
| GS.Peer_already_in_mesh | Unexpected_grafting_peer -> ()
| Grafting_successfully ->
Introspection.update_count_recv_grafts state.stats `Incr ;
()
| Peer_filtered | Unsubscribed_topic | Grafting_direct_peer
| Grafting_peer_with_negative_score | Peer_backed_off ->
do_prune ~do_px:false
| Mesh_full ->
Introspection.update_count_recv_grafts state.stats `Incr ;
do_prune ~do_px:true
in
state
(** When a [Subscribe] request from a remote peer is received, the worker just
forwards it to the automaton. There is nothing else to do. *)
let handle_subscribe = function
| state, (GS.Subscribed | Subscribe_to_unknown_peer) -> state
(** When a [Unsubscribe] request from a remote peer is received, the worker just
forwards it to the automaton. There is nothing else to do. *)
let handle_unsubscribe = function
| state, (GS.Unsubscribed | Unsubscribe_from_unknown_peer) -> state
(** When an [IHave] control message from a remote peer is received, the
automaton checks whether it is interested is some full messages whose ids
are given. If so, the worker requests them from the remote peer via an
[IWant] message. *)
let handle_ihave ({peer; _} : GS.ihave) = function
| state, GS.Message_requested_message_ids message_ids ->
Introspection.update_count_recv_ihaves state.stats
@@ `Plus (List.length message_ids) ;
if not (List.is_empty message_ids) then
emit_p2p_message state (IWant {message_ids}) (Seq.return peer) ;
state
| ( state,
( GS.Ihave_from_peer_with_low_score _ | Too_many_recv_ihave_messages _
| Too_many_sent_iwant_messages _ | Message_topic_not_tracked
| Invalid_message_id ) ) ->
state
(** When an [IWant] control message from a remote peer is received, the
automaton checks which full messages it can send back (based on message
availability and on the number of received requests). Selected messages,
if any, are transmitted to the remote peer via [Message_with_header]. *)
let handle_iwant ({peer; _} : GS.iwant) = function
| state, GS.On_iwant_messages_to_route {routed_message_ids} ->
Message_id.Map.iter
(fun message_id status ->
match status with
| `Message message ->
Introspection.update_count_recv_iwants state.stats `Incr ;
let topic = Message_id.get_topic message_id in
let = {message; topic; message_id} in
let p2p_message = Message_with_header message_with_header in
emit_p2p_message state p2p_message (Seq.return peer)
| _ -> ())
routed_message_ids ;
state
| state, GS.Iwant_from_peer_with_low_score _ ->
state
(** When a [Prune] control message from a remote peer is received, the
automaton removes that peer from the given topic's mesh. It also filters
the given collection of alternative peers to connect to. The worker then
asks the P2P part to connect to those peeers. *)
let handle_prune ~from_peer input_px =
let forget_all state =
emit_p2p_output
state
~mk_output:(fun to_peer -> Forget {peer = to_peer; origin = from_peer})
input_px
in
function
| state, (GS.Prune_topic_not_tracked | Peer_not_in_mesh) ->
forget_all state ;
state
| state, (Ignore_PX_score_too_low _ | No_PX) ->
Introspection.update_count_recv_prunes state.stats `Incr ;
forget_all state ;
state
| state, GS.PX peers ->
Introspection.update_count_recv_prunes state.stats `Incr ;
emit_p2p_output
state
~mk_output:(fun to_peer ->
Connect {peer = to_peer; origin = PX from_peer})
(Peer.Set.to_seq peers) ;
emit_p2p_output
state
~mk_output:(fun to_peer ->
Forget {peer = to_peer; origin = from_peer})
(Peer.Set.to_seq @@ Peer.Set.(diff (of_seq input_px) peers)) ;
state
(** On a [Heartbeat] events, the worker sends graft and prune messages
following the automaton's output. It also sends [IHave] messages (computed
by the automaton as well). *)
let handle_heartheat = function
| state, GS.Heartbeat {to_graft; to_prune; noPX_peers} ->
let gstate = state.gossip_state in
let gstate_view = View.view gstate in
let iter pmap mk_msg =
Peer.Map.iter
(fun peer topicset ->
Topic.Set.iter
(fun topic ->
emit_p2p_message state (mk_msg peer topic) (Seq.return peer))
topicset)
pmap
in
iter to_graft (fun _peer topic -> Graft {topic}) ;
let backoff = View.(limits gstate_view).prune_backoff in
iter to_prune (fun peer_to_prune topic ->
let px =
GS.select_px_peers gstate ~peer_to_prune topic ~noPX_peers
|> List.to_seq
in
Prune {topic; px; backoff}) ;
GS.select_gossip_messages gstate
|> List.iter (fun GS.{peer; topic; message_ids} ->
if not (List.is_empty message_ids) then
emit_p2p_message
state
(IHave {topic; message_ids})
(Seq.return peer)) ;
if Int64.(equal (rem gstate_view.heartbeat_ticks 15L) 0L) then (
Peer.Set.fold
(fun trusted_peer seq ->
if View.Connections.mem trusted_peer gstate_view.View.connections
then seq
else Seq.cons trusted_peer seq)
state.trusted_peers
Seq.empty
|> emit_p2p_output state ~mk_output:(fun trusted_peer ->
Connect {peer = trusted_peer; origin = Trusted}) ;
let p2p_output_stream = state.p2p_output_stream in
Point.Set.iter
(fun point -> Stream.push (Connect_point {point}) p2p_output_stream)
state.bootstrap_points) ;
state
let update_gossip_state state (gossip_state, output) =
({state with gossip_state}, output)
(** Handling application events. *)
let apply_app_event ({gossip_state; _} as state) = function
| Publish_message {message; message_id; topic} ->
let publish_message = GS.{topic; message_id; message} in
GS.publish_message publish_message gossip_state
|> update_gossip_state state
|> handle_publish_message publish_message
| Join topic ->
GS.join {topic} gossip_state
|> update_gossip_state state |> handle_join topic
| Leave topic ->
GS.leave {topic} gossip_state
|> update_gossip_state state |> handle_leave topic
(** Handling messages received from the P2P network. *)
let apply_p2p_message ({gossip_state; _} as state) from_peer = function
| Message_with_header {message; topic; message_id} ->
let receive_message =
{GS.sender = from_peer; topic; message_id; message}
in
GS.handle_receive_message receive_message gossip_state
|> update_gossip_state state
|> handle_receive_message receive_message
| Graft {topic} ->
let graft : GS.graft = {peer = from_peer; topic} in
GS.handle_graft graft gossip_state
|> update_gossip_state state
|> handle_graft from_peer topic
| Subscribe {topic} ->
let subscribe : GS.subscribe = {peer = from_peer; topic} in
GS.handle_subscribe subscribe gossip_state
|> update_gossip_state state |> handle_subscribe
| Unsubscribe {topic} ->
let unsubscribe : GS.unsubscribe = {peer = from_peer; topic} in
GS.handle_unsubscribe unsubscribe gossip_state
|> update_gossip_state state |> handle_unsubscribe
| IHave {topic; message_ids} ->
let ihave : GS.ihave = {peer = from_peer; topic; message_ids} in
GS.handle_ihave ihave gossip_state
|> update_gossip_state state |> handle_ihave ihave
| IWant {message_ids} ->
let iwant : GS.iwant = {peer = from_peer; message_ids} in
GS.handle_iwant iwant gossip_state
|> update_gossip_state state |> handle_iwant iwant
| Prune {topic; px; backoff} ->
let prune : GS.prune = {peer = from_peer; topic; px; backoff} in
GS.handle_prune prune gossip_state
|> update_gossip_state state |> handle_prune ~from_peer px
(** Handling events received from P2P layer. *)
let apply_p2p_event ({gossip_state; _} as state) = function
| New_connection {peer; direct; trusted; bootstrap} ->
GS.add_peer {direct; outbound = trusted; peer} gossip_state
|> update_gossip_state state
|> handle_new_connection peer ~bootstrap ~trusted
| Disconnection {peer} ->
GS.remove_peer {peer} gossip_state
|> update_gossip_state state |> handle_disconnection peer
| In_message {from_peer; p2p_message} ->
apply_p2p_message state from_peer p2p_message
(** This is the main function of the worker. It interacts with the Gossipsub
automaton given an event. The function possibly sends messages to the P2P
and application layers and returns the new worker's state. *)
let apply_event ({gossip_state; _} as state) = function
| Heartbeat ->
GS.heartbeat gossip_state |> update_gossip_state state
|> handle_heartheat
| P2P_input event -> apply_p2p_event state event
| App_input event -> apply_app_event state event
(** A helper function that pushes events in the state *)
let push e {status = _; state} = Stream.push e state.events_stream
let app_input t input = push (App_input input) t
let p2p_input t input = push (P2P_input input) t
(** This function returns a {!cancellation_handle} for a looping monad
that pushes [Heartbeat] events in the [t.events_stream] every
[heartbeat_span].
When the loop is canceled, the returned monad may take up to
[heartbeat_span] to resolve. *)
let heartbeat_events_producer ~heartbeat_span t =
let open Monad in
let shutdown = ref false in
let stream = t.state.events_stream in
let rec loop () =
let* () = Monad.sleep heartbeat_span in
Stream.push Heartbeat stream ;
if !shutdown then return () else loop ()
in
let promise = loop () in
let schedule_cancellation () =
shutdown := true ;
promise
in
{schedule_cancellation}
(** This function returns a {!cancellation_handle} for a looping monad
that consumes pushed events in [t.events_stream], if any.
When the loop is canceled, the returned monad will need an additional
extra event to consume in order to resolve. *)
let event_loop t =
let open Monad in
let shutdown = ref false in
let events_stream = t.state.events_stream in
let events_logging = t.state.events_logging in
let rec loop t =
let* event = Stream.pop events_stream in
if !shutdown then return ()
else
let* () = events_logging event in
t.state <- apply_event t.state event ;
loop t
in
let promise = loop t in
let schedule_cancellation () =
shutdown := true ;
promise
in
{schedule_cancellation}
let start topics t =
match t.status with
| Starting ->
let heartbeat_span =
View.((view t.state.gossip_state).limits.heartbeat_interval)
in
let heartbeat_handle = heartbeat_events_producer ~heartbeat_span t in
let event_loop_handle = event_loop t in
let status = Running {heartbeat_handle; event_loop_handle} in
t.status <- status ;
List.iter (fun topic -> app_input t (Join topic)) topics
| Running _ ->
Format.eprintf "A worker is already running for this state!@." ;
assert false
(** Shutting down may require waiting up [heartbeat_span] to stop the
heartbeat event loop. *)
let shutdown state =
let open C.Monad in
match state.status with
| Starting -> return ()
| Running {heartbeat_handle; event_loop_handle; _} ->
let event_loop_promise = event_loop_handle.schedule_cancellation () in
let* () = heartbeat_handle.schedule_cancellation () in
event_loop_promise
let make ?(events_logging = fun _event -> Monad.return ())
?(bootstrap_points = []) rng limits parameters =
{
status = Starting;
state =
{
bootstrap_points = Point.Set.of_list bootstrap_points;
stats = Introspection.empty_stats ();
gossip_state = GS.make rng limits parameters;
trusted_peers = Peer.Set.empty;
connected_bootstrap_peers = Peer.Set.empty;
events_stream = Stream.empty ();
p2p_output_stream = Stream.empty ();
app_output_stream = Stream.empty ();
events_logging;
};
}
let stats t = t.state.stats
let p2p_output_stream t = t.state.p2p_output_stream
let app_output_stream t = t.state.app_output_stream
let input_events_stream t = t.state.events_stream
let is_subscribed t topic =
GS.Introspection.(has_joined topic (view t.state.gossip_state))
let pp_list pp_elt =
Format.pp_print_list ~pp_sep:(fun fmt () -> Format.fprintf fmt "; ") pp_elt
let fmt {message; message_id; topic} =
Format.fprintf
fmt
"Message_with_header{message=%a, message_id=%a, topic=%a}"
Message.pp
message
Message_id.pp
message_id
Topic.pp
topic
let pp_p2p_message fmt = function
| Graft {topic} -> Format.fprintf fmt "Graft{topic=%a}" Topic.pp topic
| Prune {topic; px; backoff} ->
Format.fprintf
fmt
"Prune{topic=%a, px=%a, backoff=%a}"
Topic.pp
topic
(pp_list Peer.pp)
(List.of_seq px)
GS.Span.pp
backoff
| IHave {topic; message_ids} ->
Format.fprintf
fmt
"IHave{topic=%a, message_ids=%a}"
Topic.pp
topic
(pp_list Message_id.pp)
message_ids
| IWant {message_ids} ->
Format.fprintf
fmt
"IWant{message_ids=%a}"
(pp_list Message_id.pp)
message_ids
| Subscribe {topic} ->
Format.fprintf fmt "Subscribe{topic=%a}" Topic.pp topic
| Unsubscribe {topic} ->
Format.fprintf fmt "Unsubscribe{topic=%a}" Topic.pp topic
| Message_with_header ->
pp_message_with_header fmt message_with_header
let pp_p2p_output fmt = function
| Disconnect {peer} -> Format.fprintf fmt "Disconnect{peer=%a}" Peer.pp peer
| Kick {peer} -> Format.fprintf fmt "Kick{peer=%a}" Peer.pp peer
| Connect {peer; origin} ->
Format.fprintf
fmt
"Connect{peer=%a; origin=%a}"
Peer.pp
peer
(fun fmt origin ->
match origin with
| PX peer -> Peer.pp fmt peer
| Trusted -> Format.fprintf fmt "(trusted)")
origin
| Connect_point {point} ->
Format.fprintf fmt "Connect_point{point=%a}" Point.pp point
| Forget {peer; origin} ->
Format.fprintf
fmt
"Forget{peer=%a; origin=%a}"
Peer.pp
peer
Peer.pp
origin
| Out_message {to_peer; p2p_message} ->
Format.fprintf
fmt
"Out_message{peer=%a, p2p_message=%a}"
Peer.pp
to_peer
pp_p2p_message
p2p_message
let pp_app_output = pp_message_with_header
end