From cd0407973f70ade9f16cca38b28e72ece1bdf984 Mon Sep 17 00:00:00 2001 From: Simon Cruanes Date: Wed, 2 Jul 2025 22:44:28 -0400 Subject: [PATCH] echo example with lwt --- echo_lwt.sh | 2 + examples/dune | 16 +- examples/echo_lwt.ml | 377 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 393 insertions(+), 2 deletions(-) create mode 100755 echo_lwt.sh create mode 100644 examples/echo_lwt.ml diff --git a/echo_lwt.sh b/echo_lwt.sh new file mode 100755 index 00000000..dd5317bc --- /dev/null +++ b/echo_lwt.sh @@ -0,0 +1,2 @@ +#!/bin/sh +exec dune exec --display=quiet --profile=release "examples/echo_lwt.exe" -- $@ diff --git a/examples/dune b/examples/dune index 08d06886..a596ab63 100644 --- a/examples/dune +++ b/examples/dune @@ -8,11 +8,23 @@ (modules sse_client) (libraries unix)) +(library + (name example_vfs) + (wrapped false) + (modules vfs) + (libraries tiny_httpd)) + (executable (name echo) (flags :standard -warn-error -a+8) - (modules echo vfs) - (libraries tiny_httpd logs tiny_httpd_camlzip tiny_httpd.multipart-form-data)) + (modules echo) + (libraries tiny_httpd logs tiny_httpd_camlzip tiny_httpd.multipart-form-data example_vfs)) + +(executable + (name echo_lwt) + (flags :standard -warn-error -a+8) + (modules echo_lwt) + (libraries tiny_httpd tiny_httpd_lwt logs tiny_httpd_camlzip tiny_httpd.multipart-form-data example_vfs)) (executable (name writer) diff --git a/examples/echo_lwt.ml b/examples/echo_lwt.ml new file mode 100644 index 00000000..6b46d3c0 --- /dev/null +++ b/examples/echo_lwt.ml @@ -0,0 +1,377 @@ +open Tiny_httpd_core +module Log = Tiny_httpd.Log +module MFD = Tiny_httpd_multipart_form_data +module Task = Tiny_httpd_lwt.Task + +let now_ = Unix.gettimeofday + +let alice_text = + "CHAPTER I. Down the Rabbit-Hole Alice was beginning to get very tired of \ + sitting by her sister on the bank, and of having nothing to do: once or \ + twice she had peeped into the book her sister was reading, but it had no \ + pictures or conversations in it, thought \ + Alice So she was considering in her \ + own mind (as well as she could, for the hot day made her feel very sleepy \ + and stupid), whether the pleasure of making a daisy-chain would be worth \ + the trouble of getting up and picking the daisies, when suddenly a White \ + Rabbit with pink eyes ran close by her. There was nothing so very \ + remarkable in that; nor did Alice think it so very much out of the way to \ + hear the Rabbit say to itself, (when \ + she thought it over afterwards, it occurred to her that she ought to have \ + wondered at this, but at the time it all seemed quite natural); but when \ + the Rabbit actually took a watch out of its waistcoat-pocket, and looked at \ + it, and then hurried on, Alice started to her feet, for it flashed across \ + her mind that she had never before seen a rabbit with either a \ + waistcoat-pocket, or a watch to take out of it, and burning with curiosity, \ + she ran across the field after it, and fortunately was just in time to see \ + it pop down a large rabbit-hole under the hedge. In another moment down \ + went Alice after it, never once considering how in the world she was to get \ + out again. The rabbit-hole went straight on like a tunnel for some way, and \ + then dipped suddenly down, so suddenly that Alice had not a moment to think \ + about stopping herself before she found herself falling down a very deep \ + well. Either the well was very deep, or she fell very slowly, for she had \ + plenty of time as she went down to look about her and to wonder what was \ + going to happen next. First, she tried to look down and make out what she \ + was coming to, but it was too dark to see anything; then she looked at the \ + sides of the well, and noticed that they were filled with cupboards......" + +(* util: a little middleware collecting statistics *) +let middleware_stat () : Server.Middleware.t * (unit -> string) = + let n_req = ref 0 in + let total_time_ = ref 0. in + let parse_time_ = ref 0. in + let build_time_ = ref 0. in + let write_time_ = ref 0. in + + let m h req ~resp = + incr n_req; + let t1 = Request.start_time req in + let t2 = now_ () in + h req ~resp:(fun response -> + let t3 = now_ () in + resp response; + let t4 = now_ () in + total_time_ := !total_time_ +. (t4 -. t1); + parse_time_ := !parse_time_ +. (t2 -. t1); + build_time_ := !build_time_ +. (t3 -. t2); + write_time_ := !write_time_ +. (t4 -. t3)) + and get_stat () = + Printf.sprintf + "%d requests (average response time: %.3fms = %.3fms + %.3fms + %.3fms)" + !n_req + (!total_time_ /. float !n_req *. 1e3) + (!parse_time_ /. float !n_req *. 1e3) + (!build_time_ /. float !n_req *. 1e3) + (!write_time_ /. float !n_req *. 1e3) + in + m, get_stat + +(* ugly AF *) +let base64 x = + let ic, oc = Unix.open_process "base64" in + output_string oc x; + flush oc; + close_out oc; + let r = input_line ic in + ignore (Unix.close_process (ic, oc)); + r + +let setup_logging () = + Logs.set_reporter @@ Logs.format_reporter (); + Logs.set_level ~all:true (Some Logs.Debug) + +let setup_upload server : unit = + Server.add_route_handler_stream ~meth:`POST server + Route.(exact "upload" @/ return) + (fun req -> + let (`boundary boundary) = + match MFD.parse_content_type req.headers with + | Some b -> b + | None -> Response.fail_raise ~code:400 "no boundary found" + in + + let st = MFD.create ~boundary req.body in + let tbl = Hashtbl.create 16 in + let cur = ref "" in + let cur_kind = ref "" in + let buf = Buffer.create 16 in + let rec loop () = + match MFD.next st with + | End_of_input -> + if !cur <> "" then + Hashtbl.add tbl !cur (!cur_kind, Buffer.contents buf) + | Part headers -> + if !cur <> "" then + Hashtbl.add tbl !cur (!cur_kind, Buffer.contents buf); + (match MFD.Content_disposition.parse headers with + | Some { kind; name = Some name; filename = _ } -> + cur := name; + cur_kind := kind; + Buffer.clear buf; + loop () + | _ -> Response.fail_raise ~code:400 "content disposition missing") + | Read sl -> + Buffer.add_subbytes buf sl.bytes sl.off sl.len; + loop () + in + loop (); + + let open Tiny_httpd_html in + let data = + Hashtbl.fold + (fun name (kind, data) acc -> + Printf.sprintf "%S (kind: %S): %S" name kind data :: acc) + tbl [] + in + let html = + body [] + [ + pre [] + [ txt (Printf.sprintf "{\n%s\n}" @@ String.concat "\n" data) ]; + ] + in + Response.make_string ~code:201 @@ Ok (to_string_top html)) + +let () = + let port_ = ref 8080 in + let j = ref 32 in + let addr = ref "127.0.0.1" in + Arg.parse + (Arg.align + [ + "--port", Arg.Set_int port_, " set port"; + "-p", Arg.Set_int port_, " set port"; + "--debug", Arg.Unit setup_logging, " enable debug"; + "-j", Arg.Set_int j, " maximum number of connections"; + "--addr", Arg.Set_string addr, " binding address"; + ]) + (fun _ -> raise (Arg.Bad "")) + "echo [option]*"; + + Lwt_main.run @@ Task.run + @@ fun () -> + let server = + Tiny_httpd_lwt.create ~addr:!addr ~port:!port_ ~max_connections:!j () + |> Task.await + in + + Tiny_httpd_camlzip.setup ~compress_above:1024 ~buf_size:(16 * 1024) server; + let m_stats, get_stats = middleware_stat () in + Server.add_middleware server ~stage:(`Stage 1) m_stats; + + (* say hello *) + Server.add_route_handler ~meth:`GET server + Route.(exact "hello" @/ string @/ return) + (fun name _req -> Response.make_string (Ok ("hello " ^ name ^ "!\n"))); + + (* compressed file access *) + Server.add_route_handler ~meth:`GET server + Route.(exact "zcat" @/ string_urlencoded @/ return) + (fun path _req -> + let ic = open_in path in + let str = IO.Input.of_in_channel ic in + let mime_type = + try + let p = Unix.open_process_in (Printf.sprintf "file -i -b %S" path) in + try + let s = [ "Content-Type", String.trim (input_line p) ] in + ignore @@ Unix.close_process_in p; + s + with _ -> + ignore @@ Unix.close_process_in p; + [] + with _ -> [] + in + Response.make_stream ~headers:mime_type (Ok str)); + + (* echo request *) + Server.add_route_handler server + Route.(exact "echo" @/ return) + (fun req -> + let q = + Request.query req + |> List.map (fun (k, v) -> Printf.sprintf "%S = %S" k v) + |> String.concat ";" + in + Response.make_string + (Ok (Format.asprintf "echo:@ %a@ (query: %s)@." Request.pp req q))); + + (* file upload *) + Server.add_route_handler_stream ~meth:`PUT server + Route.(exact "upload" @/ string @/ return) + (fun path req -> + Log.debug (fun k -> + k "start upload %S, headers:\n%s\n\n%!" path + (Format.asprintf "%a" Headers.pp (Request.headers req))); + try + let oc = open_out @@ "/tmp/" ^ path in + IO.Input.to_chan oc req.Request.body; + flush oc; + Response.make_string (Ok "uploaded file") + with e -> + Response.fail ~code:500 "couldn't upload file: %s" + (Printexc.to_string e)); + + (* protected by login *) + Server.add_route_handler server + Route.(exact "protected" @/ return) + (fun req -> + let ok = + match Request.get_header req "authorization" with + | Some v -> + Log.debug (fun k -> k "authenticate with %S" v); + v = "Basic " ^ base64 "user:foobar" + | None -> false + in + if ok then ( + (* FIXME: a logout link *) + let s = + "

hello, this is super secret!

log out" + in + Response.make_string (Ok s) + ) else ( + let headers = + Headers.(empty |> set "www-authenticate" "basic realm=\"echo\"") + in + Response.fail ~code:401 ~headers "invalid" + )); + + (* logout *) + Server.add_route_handler server + Route.(exact "logout" @/ return) + (fun _req -> Response.fail ~code:401 "logged out"); + + (* stats *) + Server.add_route_handler server + Route.(exact "stats" @/ return) + (fun _req -> + let stats = get_stats () in + Response.make_string @@ Ok stats); + + Server.add_route_handler server + Route.(exact "alice" @/ return) + (fun _req -> Response.make_string (Ok alice_text)); + + Server.add_route_handler ~meth:`HEAD server + Route.(exact "head" @/ return) + (fun _req -> + Response.make_void ~code:200 ~headers:[ "x-hello", "world" ] ()); + + (* VFS *) + Tiny_httpd.Dir.add_vfs server + ~config: + (Tiny_httpd.Dir.config ~download:true + ~dir_behavior:Tiny_httpd.Dir.Index_or_lists ()) + ~vfs:Vfs.vfs ~prefix:"vfs"; + + setup_upload server; + + (* main page *) + Server.add_route_handler server + Route.(return) + (fun _req -> + let open Tiny_httpd_html in + let h = + html [] + [ + head [] [ title [] [ txt "index of echo" ] ]; + body [] + [ + h3 [] [ txt "welcome!" ]; + p [] [ b [] [ txt "endpoints are:" ] ]; + ul [] + [ + li [] [ pre [] [ txt "/hello/:name (GET)" ] ]; + li [] + [ + pre [] + [ + a [ A.href "/echo/" ] [ txt "echo" ]; + txt " echo back query"; + ]; + ]; + li [] + [ pre [] [ txt "/upload/:path (PUT) to upload a file" ] ]; + li [] + [ + pre [] + [ + txt + "/zcat/:path (GET) to download a file (deflate \ + transfer-encoding)"; + ]; + ]; + li [] + [ + pre [] + [ + a [ A.href "/stats/" ] [ txt "/stats/" ]; + txt " (GET) to access statistics"; + ]; + ]; + li [] + [ + pre [] + [ + a [ A.href "/vfs/" ] [ txt "/vfs" ]; + txt " (GET) to access a VFS embedded in the binary"; + ]; + ]; + li [] + [ + pre [] + [ + a [ A.href "/protected" ] [ txt "/protected" ]; + txt + " (GET) to see a protected page (login: user, \ + password: foobar)"; + ]; + ]; + li [] + [ + pre [] + [ + a [ A.href "/logout" ] [ txt "/logout" ]; + txt " (POST) to log out"; + ]; + ]; + li [] + [ + form + [ + A.action "/upload"; + A.enctype "multipart/form-data"; + A.target "_self"; + A.method_ "POST"; + ] + [ + label [] [ txt "my beautiful form" ]; + input [ A.type_ "file"; A.name "file1" ]; + input [ A.type_ "file"; A.name "file2" ]; + input + [ + A.type_ "text"; + A.name "a"; + A.placeholder "text A"; + ]; + input + [ + A.type_ "text"; + A.name "b"; + A.placeholder "text B"; + ]; + input [ A.type_ "submit" ]; + ]; + ]; + ]; + ]; + ] + in + let s = to_string_top h in + Response.make_string ~headers:[ "content-type", "text/html" ] @@ Ok s); + + Printf.printf "listening on http://%s:%d\n%!" (Server.addr server) + (Server.port server); + match Server.run server with + | Ok () -> () + | Error e -> raise e