opam-mirror/mirage/http_mirage_client.ml

338 lines
14 KiB
OCaml

let http_scheme = Mimic.make ~name:"http-scheme"
let http_port = Mimic.make ~name:"http-port"
let http_hostname = Mimic.make ~name:"http-hostname"
let http_sleep = Mimic.make ~name:"http-sleep"
let tls_config = Mimic.make ~name:"tls-config"
open Lwt.Infix
module type S = sig
val connect : Mimic.ctx -> Mimic.ctx Lwt.t
val alpn_protocol : Mimic.flow -> string option
val authenticator : (X509.Authenticator.t, [> `Msg of string ]) result
end
module Make
(Time : Mirage_time.S)
(Pclock : Mirage_clock.PCLOCK)
(TCP : Tcpip.Tcp.S)
(Happy_eyeballs : Mimic_happy_eyeballs.S with type flow = TCP.flow) : S = struct
module TCP = struct
include TCP
type endpoint = Happy_eyeballs.t * string * int
type nonrec write_error =
[ `Write of write_error | `Connect of string | `Closed ]
let pp_write_error ppf = function
| `Connect err -> Fmt.string ppf err
| `Write err -> pp_write_error ppf err
| `Closed as err -> pp_write_error ppf err
let write flow cs =
let open Lwt.Infix in
write flow cs >>= function
| Ok _ as v -> Lwt.return v
| Error err -> Lwt.return_error (`Write err)
let writev flow css =
writev flow css >>= function
| Ok _ as v -> Lwt.return v
| Error err -> Lwt.return_error (`Write err)
let connect (happy_eyeballs, hostname, port) =
Happy_eyeballs.resolve happy_eyeballs hostname [ port ] >>= function
| Error (`Msg err) -> Lwt.return_error (`Connect err)
| Ok ((_ipaddr, _port), flow) -> Lwt.return_ok flow
end
let tcp_edn, _tcp_protocol = Mimic.register ~name:"tcp" (module TCP)
module TLS = struct
type endpoint = Happy_eyeballs.t * Tls.Config.client * string * int
include Tls_mirage.Make (TCP)
let connect (happy_eyeballs, cfg, hostname, port) =
let peer_name =
Result.(to_option (bind (Domain_name.of_string hostname) Domain_name.host)) in
Happy_eyeballs.resolve happy_eyeballs hostname [ port ] >>= function
| Ok ((_ipaddr, _port), flow) -> client_of_flow cfg ?host:peer_name flow
| Error (`Msg err) -> Lwt.return_error (`Write (`Connect err))
end
let tls_edn, tls_protocol =
Mimic.register ~name:"tls" (module TLS)
let connect ctx =
let k0 happy_eyeballs http_scheme http_hostname http_port = match http_scheme with
| "http" -> Lwt.return_some (happy_eyeballs, http_hostname, http_port)
| _ -> Lwt.return_none in
let k1 happy_eyeballs http_scheme http_hostname http_port tls_config = match http_scheme with
| "https" -> Lwt.return_some (happy_eyeballs, tls_config, http_hostname, http_port)
| _ -> Lwt.return_none in
let ctx = Mimic.fold tcp_edn
Mimic.Fun.[ req Happy_eyeballs.happy_eyeballs
; req http_scheme; req http_hostname; dft http_port 80 ]
~k:k0 ctx in
let ctx = Mimic.fold tls_edn
Mimic.Fun.[ req Happy_eyeballs.happy_eyeballs
; req http_scheme; req http_hostname; dft http_port 443
; req tls_config ]
~k:k1 ctx in
Lwt.return (Mimic.add http_sleep Time.sleep_ns ctx)
let alpn_protocol flow =
let module M = (val (Mimic.repr tls_protocol)) in
match flow with
| M.T flow ->
( match TLS.epoch flow with
| Ok { Tls.Core.alpn_protocol; _ } -> alpn_protocol
| Error _ -> None )
| _ -> None
let authenticator =
let module V = Ca_certs_nss.Make (Pclock) in
V.authenticator ()
end
module Version = Httpaf.Version
module Status = H2.Status
module Headers = H2.Headers
type response =
{ version : Version.t
; status : Status.t
; reason : string
; headers : Headers.t }
module HTTP_1_1 = struct
include Httpaf.Client_connection
let yield_reader _ = assert false
let next_read_operation t =
(next_read_operation t :> [ `Close | `Read | `Yield ])
end
let add_authentication ~add headers = function
| None -> headers
| Some (user, pass) ->
let data = Base64.encode_string (user ^ ":" ^ pass) in
add headers "authorization" ("Basic " ^ data)
let prepare_http_1_1_headers headers host user_pass body_length =
let headers = Httpaf.Headers.of_list headers in
let add = Httpaf.Headers.add_unless_exists in
let headers = add headers "user-agent" ("http-mirage-client/%%VERSION%%") in
let headers = add headers "host" host in
let headers = add headers "connection" "close" in
let headers = match body_length with
| None -> headers
| Some v -> add headers "content-length" (string_of_int v) in
add_authentication ~add headers user_pass
let single_http_1_1_request ~sleep ?config flow user_pass host meth path headers body =
let body_length = Option.map String.length body in
let headers = prepare_http_1_1_headers headers host user_pass body_length in
let req = Httpaf.Request.create ~headers meth path in
let finished, notify_finished = Lwt.wait () in
let wakeup = let w = ref false in
fun v -> if not !w then Lwt.wakeup_later notify_finished v ; w := true in
let response_handler response body =
let buf = Buffer.create 0x100 in
let rec on_eof () =
let response =
{ version= response.Httpaf.Response.version
; status = (response.Httpaf.Response.status :> H2.Status.t)
; reason = response.Httpaf.Response.reason
; headers= H2.Headers.of_list (Httpaf.Headers.to_list response.Httpaf.Response.headers) } in
wakeup (Ok (response, Some (Buffer.contents buf)))
and on_read ba ~off ~len =
Buffer.add_string buf (Bigstringaf.substring ~off ~len ba) ;
Httpaf.Body.schedule_read body ~on_read ~on_eof in
let on_eof () =
let response =
{ version= response.Httpaf.Response.version
; status = (response.Httpaf.Response.status :> H2.Status.t)
; reason = response.Httpaf.Response.reason
; headers= H2.Headers.of_list (Httpaf.Headers.to_list response.Httpaf.Response.headers) } in
wakeup (Ok (response, None)) in
Httpaf.Body.schedule_read body ~on_read ~on_eof in
let error_handler e =
let err = match e with
| `Malformed_response x -> Error (`Msg ("Malformed response: " ^ x))
| `Invalid_response_body_length _ -> Error (`Msg ("Invalid response body length"))
| `Exn e -> Error (`Msg ("Exception here: " ^ Printexc.to_string e)) in
wakeup err in
let request_body, conn = Httpaf.Client_connection.request ?config req ~error_handler
~response_handler in
Lwt.async (fun () -> Paf.run (module HTTP_1_1) ~sleep conn flow) ;
Option.iter (Httpaf.Body.write_string request_body) body ;
Httpaf.Body.close_writer request_body ;
finished
let prepare_h2_headers headers host user_pass body_length =
let headers = H2.Headers.of_list headers in
let add hdr = H2.Headers.add_unless_exists hdr ?sensitive:None in
let headers = add headers ":authority" host in
let headers = add headers "content-length" (string_of_int (Option.value ~default:0 body_length)) in
add_authentication ~add headers user_pass
let single_h2_request ~sleep ?config ~scheme flow user_pass host meth path headers body =
let body_length = Option.map String.length body in
let headers = prepare_h2_headers headers host user_pass body_length in
let req = H2.Request.create ~scheme ~headers meth path in
let finished, notify_finished = Lwt.wait () in
let wakeup = let w = ref false in
fun v -> if not !w then Lwt.wakeup_later notify_finished v ; w := true in
let response_handler response response_body =
let buf = Buffer.create 0x100 in
let rec on_eof () =
let response =
{ version= { major= 2; minor= 0; }
; status = response.H2.Response.status
; reason = ""
; headers= response.H2.Response.headers } in
wakeup (Ok (response, Some (Buffer.contents buf)))
and on_read ba ~off ~len =
Buffer.add_string buf (Bigstringaf.substring ~off ~len ba) ;
H2.Body.Reader.schedule_read response_body
~on_read ~on_eof in
let on_eof () =
let response =
{ version= { major= 2; minor= 0; }
; status = response.H2.Response.status
; reason = ""
; headers= response.H2.Response.headers } in
wakeup (Ok (response, None)) in
H2.Body.Reader.schedule_read response_body
~on_read ~on_eof in
let error_handler e =
let err = match e with
| `Malformed_response x -> Error (`Msg ("Malformed response: " ^ x))
| `Invalid_response_body_length _ -> Error (`Msg "Invalid response body length")
| `Protocol_error (err, msg) ->
let kerr _ = Error (`Msg (Format.flush_str_formatter ())) in
Format.kfprintf kerr Format.str_formatter "%a: %s" H2.Error_code.pp_hum err msg
| `Exn e -> Error (`Msg ("Exception here: " ^ Printexc.to_string e)) in
wakeup err in
let conn = H2.Client_connection.create ?config ?push_handler:None
~error_handler in
let request_body = H2.Client_connection.request conn req ~error_handler ~response_handler in
Lwt.async (fun () -> Paf.run (module H2.Client_connection) ~sleep conn flow) ;
Option.iter (H2.Body.Writer.write_string request_body) body ;
H2.Body.Writer.close request_body ;
finished
let decode_uri ~ctx uri =
let ( >>= ) = Result.bind in
match String.split_on_char '/' uri with
| proto :: "" :: user_pass_host_port :: path ->
( if String.equal proto "http:"
then Ok ("http", Mimic.add http_scheme "http" ctx)
else if String.equal proto "https:"
then Ok ("https", Mimic.add http_scheme "https" ctx)
else Error (`Msg "Couldn't decode user and password") ) >>= fun (scheme, ctx) ->
let decode_user_pass up = match String.split_on_char ':' up with
| [ user; pass; ] -> Ok (user, pass)
| _ -> Error (`Msg "Couldn't decode user and password") in
( match String.split_on_char '@' user_pass_host_port with
| [ host_port ] -> Ok (None, host_port)
| [ user_pass; host_port ] ->
decode_user_pass user_pass >>= fun up ->
Ok (Some up, host_port)
| _ -> Error (`Msg "Couldn't decode URI") ) >>= fun (user_pass, host_port) ->
( match String.split_on_char ':' host_port with
| [] -> Error (`Msg "Empty host & port")
| [ hostname ] -> Ok (hostname, Mimic.add http_hostname hostname ctx)
| hd :: tl ->
let port, hostname = match List.rev (hd :: tl) with
| hd :: tl -> hd, String.concat ":" (List.rev tl)
| _ -> assert false in
( try Ok (hostname, Mimic.add http_hostname hostname (Mimic.add http_port (int_of_string port) ctx))
with Failure _ -> Error (`Msg "Couldn't decode port") ) ) >>= fun (hostname, ctx) ->
Ok (ctx, scheme, hostname, user_pass, "/" ^ String.concat "/" path)
| _ -> Error (`Msg "Couldn't decode URI on top")
let ( >>? ) = Lwt_result.bind
let alpn_protocol_of_string = function
| "http/1.1" -> Some `HTTP_1_1
| "h2" -> Some `H2
| _ -> None
let single_request ~ctx ~alpn_protocol ?config cfg ~meth ~headers ?body uri =
let sleep = Option.get (Mimic.get http_sleep ctx) in
Lwt.return (decode_uri ~ctx uri) >>? fun (ctx, scheme, host, user_pass, path) ->
let ctx = match Lazy.force cfg with
| Ok (`Custom cfg) -> Mimic.add tls_config cfg ctx
| Ok (`Default cfg) ->
( match Result.bind (Domain_name.of_string host) Domain_name.host with
| Ok peer -> Mimic.add tls_config (Tls.Config.peer cfg peer) ctx
| Error _ -> Mimic.add tls_config cfg ctx )
| Error _ -> ctx in
Mimic.resolve ctx >>? fun flow ->
match Option.bind (alpn_protocol flow) alpn_protocol_of_string, config with
| (Some `HTTP_1_1 | None), Some (`HTTP_1_1 config) ->
single_http_1_1_request ~sleep ~config flow user_pass host meth path headers body
| (Some `HTTP_1_1 | None), None ->
single_http_1_1_request ~sleep flow user_pass host meth path headers body
| (Some `H2 | None), Some (`H2 config) ->
single_h2_request ~sleep ~config ~scheme flow user_pass host meth path headers body
| Some `H2, None ->
single_h2_request ~sleep ~scheme flow user_pass host meth path headers body
| Some `H2, (Some (`HTTP_1_1 _)) ->
single_h2_request ~sleep ~scheme flow user_pass host meth path headers body
| Some `HTTP_1_1, Some (`H2 _) ->
single_http_1_1_request ~sleep flow user_pass host meth path headers body
let tls_config ?tls_config ?config authenticator =
lazy ( match tls_config with
| Some cfg -> Ok (`Custom cfg)
| None ->
let alpn_protocols = match config with
| None -> [ "h2"; "http/1.1" ]
| Some (`H2 _) -> [ "h2" ]
| Some (`HTTP_1_1 _) -> [ "http/1.1" ] in
Result.map (fun authenticator -> `Default (Tls.Config.client ~alpn_protocols ~authenticator ())) authenticator )
let resolve_location ~uri ~location =
match String.split_on_char '/' location with
| "http:" :: "" :: _ -> Ok location
| "https:" :: "" :: _ -> Ok location
| "" :: "" :: _ ->
let schema = String.sub uri 0 (String.index uri '/') in
Ok (schema ^ location)
| "" :: _ ->
(match String.split_on_char '/' uri with
| schema :: "" :: user_pass_host_port :: _ ->
Ok (String.concat "/" [schema ; "" ; user_pass_host_port ^ location])
| _ -> Error (`Msg ("expected an absolute uri, got: " ^ uri)))
| _ -> Error (`Msg ("unknown location (relative path): " ^ location))
let one_request
?config
?tls_config:cfg
~ctx
~alpn_protocol
~authenticator
?(meth= `GET)
?(headers= [])
?body
?(max_redirect= 5)
?(follow_redirect= true) uri =
let tls_config = tls_config ?tls_config:cfg ?config authenticator in
if not follow_redirect
then single_request ~ctx ~alpn_protocol ?config tls_config ~meth ~headers ?body uri
else
let rec follow_redirect count uri =
if count = 0 then Lwt.return_error (`Msg "Redirect limit exceeded")
else
single_request ~ctx ~alpn_protocol ?config tls_config ~meth ~headers ?body uri
>>? fun (resp, body) ->
match resp.status with
| #Status.redirection ->
( match Headers.get resp.headers "location" with
| Some location ->
Lwt.return (resolve_location ~uri ~location) >>? fun uri ->
follow_redirect (pred count) uri
| None -> Lwt.return_ok (resp, body) )
| _ -> Lwt.return_ok (resp, body) in
follow_redirect max_redirect uri