(*****************************************************************************)
(* *)
(* 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. *)
(* *)
(*****************************************************************************)
type attempt_event = {attempt : int; delay : float; text : string}
module Attempt_logging = Internal_event.Make (struct
type t = attempt_event
let section = None
let name = "rpc_http_attempt"
let doc = "Error emitted when an HTTP request returned a 502 error."
let encoding =
Data_encoding.(
conv
(fun {attempt; delay; text} -> (attempt, delay, text))
(fun (attempt, delay, text) -> {attempt; delay; text})
(obj3 (req "attempt" int8) (req "delay" float) (req "text" string)))
let pp ~all_fields:_ ~block:_ f {attempt; delay; text} =
Format.fprintf
f
"Attempt number %d/10, will retry after %g seconds.\n\
Original body follows.\n\
%s"
attempt
delay
text
let level = Internal_event.Error
end)
module RetryClient : Cohttp_lwt.S.Client = struct
include Cohttp_lwt_unix.Client
let clone_body = function `Stream s -> `Stream (Lwt_stream.clone s) | x -> x
let call ?ctx ?headers ?body ?chunked meth uri =
let rec call_and_retry_on_502 attempt delay =
let open Lwt_syntax in
let* response, ansbody = call ?ctx ?headers ?body ?chunked meth uri in
let status = Cohttp.Response.status response in
match status with
| `Bad_gateway ->
let log_ansbody = clone_body ansbody in
let* text = Cohttp_lwt.Body.to_string log_ansbody in
let* _ = Attempt_logging.emit {attempt; delay; text} in
if attempt >= 10 then return (response, ansbody)
else
let* () = Lwt_unix.sleep delay in
call_and_retry_on_502 (attempt + 1) (delay +. 0.1)
| _ -> return (response, ansbody)
in
call_and_retry_on_502 1 0.
end
include RPC_client.Make (Resto_cohttp_client.Client.OfCohttp (RetryClient))