ligo/src/lib_shell/mempool_peer_worker.ml
2018-12-17 15:20:08 +01:00

401 lines
14 KiB
OCaml

(*****************************************************************************)
(* *)
(* Open Source License *)
(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
(* *)
(* Permission is hereby granted, free of charge, to any person obtaining a *)
(* copy of this software and associated documentation files (the "Software"),*)
(* to deal in the Software without restriction, including without limitation *)
(* the rights to use, copy, modify, merge, publish, distribute, sublicense, *)
(* and/or sell copies of the Software, and to permit persons to whom the *)
(* Software is furnished to do so, subject to the following conditions: *)
(* *)
(* The above copyright notice and this permission notice shall be included *)
(* in all copies or substantial portions of the Software. *)
(* *)
(* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*)
(* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *)
(* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL *)
(* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER*)
(* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING *)
(* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER *)
(* DEALINGS IN THE SOFTWARE. *)
(* *)
(*****************************************************************************)
(** Validating batches of operations with some peer-based
* compartimentatilsation. *)
type limits = {
max_promises_per_request : int ;
worker_limits : Worker_types.limits ;
}
module type T = sig
module Mempool_worker: Mempool_worker.T
type t
type input = Operation_hash.t list
val create: limits -> P2p_peer.Id.t -> Mempool_worker.t -> t Lwt.t
val shutdown: t -> input Lwt.t
val validate: t -> input -> unit tzresult Lwt.t
end
module Make (Mempool_worker: Mempool_worker.T)
: T with module Mempool_worker = Mempool_worker
= struct
(* 0. Prelude: set up base modules and types *)
(* See interface file for info if needed. *)
module Proto = Mempool_worker.Proto
module Mempool_worker = Mempool_worker
type input = Operation_hash.t list
type result =
| Cannot_download of error list
| Cannot_parse of error list
| Cannot_validate of error list
| Mempool_result of Mempool_worker.result
type output = result Operation_hash.Map.t
let pp_input = Format.pp_print_list Operation_hash.pp
let result_encoding =
let open Data_encoding in
union
[ case (Tag 0)
~title:"Cannot download"
(obj1 (req "download_errors" (list Error_monad.error_encoding)))
(function Cannot_download errs -> Some errs | _ -> None)
(fun errs -> Cannot_download errs) ;
case (Tag 1)
~title:"Cannot parse"
(obj1 (req "parse_errors" (list Error_monad.error_encoding)))
(function Cannot_parse errs -> Some errs | _ -> None)
(fun errs -> Cannot_parse errs) ;
case (Tag 2)
~title:"Cannot validate"
(obj1 (req "validation_errors" (list Error_monad.error_encoding)))
(function Cannot_validate errs -> Some errs | _ -> None)
(fun errs -> Cannot_validate errs) ;
case (Tag 3)
~title:"Validation result"
(obj1 (req "validation_result" Mempool_worker.result_encoding))
(function Mempool_result result -> Some result | _ -> None)
(fun result -> Mempool_result result) ]
module Log = Tezos_stdlib.Logging.Make(struct
let name = "node.mempool.peer_worker"
end)
(* 1. Core: the carefully scheduled work performed by the worker *)
module Work : sig
val work: Mempool_worker.t -> int -> input -> output Lwt.t
end = struct
type t = {
pool: unit Lwt_pool.t;
received: Operation_hash.t Queue.t;
downloading: (Operation_hash.t * Operation.t tzresult Lwt.t) Queue.t;
applying: (Mempool_worker.operation * Mempool_worker.result tzresult Lwt.t) Queue.t;
mutable results: result Operation_hash.Map.t
}
(* Primitives *)
let is_empty t =
Queue.is_empty t.received &&
Queue.is_empty t.downloading &&
Queue.is_empty t.applying
let has_resolved t = match Lwt.state t with
| Lwt.Return _ | Lwt.Fail _ -> true
| Lwt.Sleep -> false
let head_is_resolved q =
(not (Queue.is_empty q)) && has_resolved (snd (Queue.peek q))
let select t =
(* A `select`-like function to wait on any of the pipeline's buffers'
* heads to resolve *)
assert (not (Queue.is_empty t.downloading && Queue.is_empty t.applying));
let first_task_or_never q =
if Queue.is_empty q then
Lwt_utils.never_ending ()
else
snd (Queue.peek q) >>= fun _ -> Lwt.return_unit
in
Lwt.choose (
(first_task_or_never t.downloading) ::
(first_task_or_never t.applying) ::
[]
)
let record_result pipeline op_hash result =
pipeline.results <- Operation_hash.Map.add op_hash result pipeline.results
let q_of_list l =
let q = Queue.create () in
List.iter (fun x -> Queue.add x q) l;
q
let create pool_size op_hashes =
{
pool = Lwt_pool.create pool_size Lwt.return;
received = q_of_list op_hashes;
downloading = Queue.create ();
applying = Queue.create ();
results = Operation_hash.Map.empty;
}
let cancel pipeline =
let cancel_snd (_, p) = Lwt.cancel p in
Queue.iter cancel_snd pipeline.downloading;
Queue.iter cancel_snd pipeline.applying
(* Exported interactions *)
let step mempool_worker pipeline =
(* Going through each buffer one by one. *)
(* op_hash: Opertation_hash.t
* op: Operation.t
* mop: Mempool_worker.operation *)
if head_is_resolved pipeline.applying then begin
let (op, p) = Queue.pop pipeline.applying in
p >>= function
| Error errs ->
record_result pipeline op.hash (Cannot_validate errs);
Lwt.return_unit
| Ok mempool_result ->
record_result pipeline op.hash (Mempool_result mempool_result);
Lwt.return_unit
end
else if head_is_resolved pipeline.downloading then begin
let (op_hash, p) = Queue.pop pipeline.downloading in
p >>= function
| Error errs ->
record_result pipeline op_hash (Cannot_download errs);
Lwt.return_unit
| Ok op ->
match Mempool_worker.parse op with
| Error errs ->
record_result pipeline op_hash (Cannot_parse errs);
Lwt.return_unit
| Ok mop ->
let p =
Lwt_pool.use pipeline.pool (fun () ->
Mempool_worker.validate mempool_worker mop) in
Queue.push (mop, p) pipeline.applying;
Lwt.return_unit
end
else if (not (Queue.is_empty pipeline.received)) then begin
let op_hash = Queue.pop pipeline.received in
(* TODO[?] should we specify the current peer for fetching? *)
let chain_db = Mempool_worker.chain_db mempool_worker in
let p =
Lwt_pool.use pipeline.pool (fun () ->
Distributed_db.Operation.fetch chain_db op_hash ()) in
Queue.push (op_hash, p) pipeline.downloading;
Lwt.return_unit
end
else
(* There are some pending operations, we need to wait on them *)
select pipeline >>= fun () ->
Lwt.return_unit
let work mempool_worker pool_size input =
let pipeline = create pool_size input in
let rec loop () =
if is_empty pipeline then
Lwt.return pipeline.results
else
step mempool_worker pipeline >>= fun () ->
loop ()
in
let work = loop () in
Lwt.on_cancel work (fun () -> cancel pipeline);
work
end
(* 2. Boilerplate: the set up for the worker architecture *)
module Name = struct
type t = P2p_peer.Id.t
let encoding = P2p_peer.Id.encoding
let base =
let proto_hash =
let _: string = Format.flush_str_formatter () in
Format.fprintf Format.str_formatter "%a" Protocol_hash.pp Proto.hash;
Format.flush_str_formatter () in
[ "node"; "mempool"; "peer_worker"; proto_hash ]
let pp = P2p_peer.Id.pp
end
module Request = struct
type 'a t = Batch : input -> output t
type view = input
let view
: type a. a t -> view
= fun (Batch os) -> os
let encoding =
let open Data_encoding in
list Operation_hash.encoding
let pp = Format.pp_print_list Operation_hash.pp
end
module Event = struct
type t =
| Start of input
| End_ok of (Request.view * Worker_types.request_status * output)
| End_error of (Request.view * Worker_types.request_status * error list)
let level req =
match req with
| Start _ -> Logging.Info
| End_ok _ -> Logging.Info
| End_error _ -> Logging.Error
let encoding =
let open Data_encoding in
union
[ case (Tag 0)
~title:"Start"
(obj1 (req "input" (list Operation_hash.encoding)))
(function Start input -> Some input | _ -> None)
(fun input -> Start input) ;
case (Tag 1)
~title:"End_ok"
(obj3
(req "request" Request.encoding)
(req "status" Worker_types.request_status_encoding)
(req "output" (Operation_hash.Map.encoding result_encoding)))
(function End_ok (view, status, result) -> Some (view, status, result) | _ -> None)
(fun (view, status, result) -> End_ok (view, status, result)) ;
case (Tag 2)
~title:"End_error"
(obj3
(req "failed_request" Request.encoding)
(req "status" Worker_types.request_status_encoding)
(req "error" RPC_error.encoding))
(function End_error (view, status, errs) -> Some (view, status, errs) | _ -> None)
(fun (view, status, errs) -> End_error (view, status, errs)) ]
let pp ppf = function
| Start input ->
Format.fprintf ppf
"@[<v 0>Starting: %a@]"
pp_input
input
| End_ok (view, _, _) ->
Format.fprintf ppf
"@[<v 0>Finished: %a@]"
Request.pp view
| End_error (view, _, errs) ->
Format.fprintf ppf
"@[<v 0>Errors: %a, Operations: %a@]"
(Format.pp_print_list Error_monad.pp) errs
Request.pp view
end
module Types = struct
type parameters = Mempool_worker.t * int
type state = { mempool_worker: Mempool_worker.t ; pool_size: int }
type view = unit
let view _ _ = ()
let encoding = Data_encoding.unit
let pp _ _ = ()
end
module Worker = Worker.Make (Name) (Event) (Request) (Types)
type t = Worker.infinite Worker.queue Worker.t
let table = Worker.create_table Queue
(* 3. Workers' work: setting workers' callbacks to perform core work *)
module Handlers = struct
type self = t
let on_launch _ _ (mempool_worker, pool_size) =
Lwt.return Types.{ mempool_worker; pool_size }
let on_request : type a. self -> a Request.t -> a tzresult Lwt.t
= fun t (Request.Batch os) ->
let st = Worker.state t in
Worker.record_event t (Event.Start os) ;
Work.work st.mempool_worker st.pool_size os >>= fun r ->
return r
let on_no_request _ = return_unit
let on_close _ = Lwt.return_unit
let on_error t view st errs =
Worker.record_event t (Event.End_error (view, st, errs)) ;
Lwt.return (Error errs)
let on_completion
: type a. self -> a Request.t -> a -> Worker_types.request_status -> unit Lwt.t
= fun t req output st ->
match req with
| Request.Batch _ ->
Worker.record_event t (Event.End_ok (Request.view req, st, output)) ;
Lwt.return_unit
end
(* 4. Public interface: exporting a thin wrapper around workers and work. *)
(* See interface file for documentation *)
let validate t os =
Worker.push_request_and_wait t (Request.Batch os)
>>=? fun (_: output) -> return_unit
let create limits peer_id mempool_worker =
Worker.launch
table
limits.worker_limits
peer_id
(mempool_worker, limits.max_promises_per_request)
(module Handlers)
let shutdown w =
let recycled = Operation_hash.Set.empty in
let recycled =
List.fold_left
(fun recycled (_, input) ->
List.fold_left
(fun recycled op_h -> Operation_hash.Set.add op_h recycled)
recycled
input)
recycled
(Worker.pending_requests w)
in
let recycled =
match Worker.current_request w with
| Some (_, _, input) ->
List.fold_left
(fun recycled op_h -> Operation_hash.Set.add op_h recycled)
recycled
input
| None -> recycled
in
let input = Operation_hash.Set.elements recycled in
Worker.shutdown w >>= fun () ->
Lwt.return input
end