deprecate file upload and implement new apis

lib/api.ml

@@ -9,6 +9,14 @@ module type S = sig
   val send_message_webhook : ctx:Context.t -> url:string -> msg:post_message_req -> unit slack_response Lwt.t
   val update_message : ctx:Context.t -> msg:update_message_req -> update_message_res slack_response Lwt.t
   val upload_file : ctx:Context.t -> file:files_upload_req -> files_upload_res slack_response Lwt.t
+  [@@deprecated "Use get_upload_url_external with \
+                 complete_upload_external as per \
+                 https://api.slack.com/messaging/files#uploading_files. Otherwise, \
+                 there is upload_file_v2 convenience function"]
+
+  val get_upload_url_external : ctx:Context.t -> req:get_upload_url_ext_req -> get_upload_url_ext_res slack_response Lwt.t
+  val complete_upload_external : ctx:Context.t -> req:complete_upload_ext_req -> complete_upload_ext_res slack_response Lwt.t
+  val upload_file_v2 : ctx:Context.t -> file:files_upload_req -> files_upload_res slack_response Lwt.t
 
   (* conversations *)
   val get_replies :

lib/api_local.ml

@@ -38,6 +38,9 @@ let default_files_res : Slack_t.file =
 
 let default_files_upload_res : Slack_t.files_upload_res = { ok = true; file = default_files_res }
 
+let default_files_upload_res_v2 : Slack_t.complete_upload_ext_res =
+  { ok = true; files = [ { id = default_files_res.id; title = default_files_res.title } ] }
+
 let send_message ~ctx:_ ~msg =
   let json = msg |> Slack_j.string_of_post_message_req |> Yojson.Basic.from_string |> Yojson.Basic.pretty_to_string in
   printf "will notify #%s\n" msg.channel;
@@ -65,6 +68,36 @@ let upload_file ~ctx:_ ~file =
     Lwt.return_ok { default_files_upload_res with file = { default_files_res with channels = [ channels ] } }
   | None -> Lwt.return_error (`Other "invalid file upload")
 
+let get_upload_url_external ~ctx:_ ~(req : Slack_t.get_upload_url_ext_req) =
+  let json =
+    req |> Slack_j.string_of_get_upload_url_ext_req |> Yojson.Basic.from_string |> Yojson.Basic.pretty_to_string
+  in
+  printf "getting upload url for %s\n" req.filename;
+  printf "%s\n" json;
+  Lwt.return_ok Slack_t.{ ok = true; upload_url = "http://fake-upload-url.com"; file_id = "file_id" }
+
+let complete_upload_external ~ctx:_ ~(req : Slack_t.complete_upload_ext_req) =
+  let json =
+    req |> Slack_j.string_of_complete_upload_ext_req |> Yojson.Basic.from_string |> Yojson.Basic.pretty_to_string
+  in
+  printf "complete upload for %s in channel:%s or ts:%s\n" (Slack_j.string_of_files_v2 req.files)
+    (Option.default "NULL" req.channel_id) (Option.default "NULL" req.thread_ts);
+  printf "%s\n" json;
+  Lwt.return_ok default_files_upload_res_v2
+
+let upload_file_v2 ~ctx:_ ~(file : Slack_t.files_upload_req) =
+  let json = file |> Slack_j.string_of_files_upload_req |> Yojson.Basic.from_string |> Yojson.Basic.pretty_to_string in
+  match file.channels with
+  | Some channels ->
+    if List.length (String.split_on_char ',' channels) <> 1 then
+      Lwt.return_error (`Other "only allowed to specify 1 channel")
+    else (
+      printf "will update #%s\n" channels;
+      printf "%s\n" json;
+      Lwt.return_ok { default_files_upload_res with file = { default_files_res with channels = [ channels ] }}
+    )
+  | None -> Lwt.return_error (`Other "invalid file upload")
+
 let join_conversation ~ctx:_ ~(channel : Slack_t.conversations_join_req) =
   printf "joining #%s...\n" channel.channel;
   let url = Filename.concat cache_dir (sprintf "%s_join" channel.channel) in

lib/api_remote.ml

@@ -105,6 +105,70 @@ let upload_file ~(ctx : Context.t) ~(file : Slack_t.files_upload_req) =
     ~name:(sprintf "file.upload (%s)" @@ Option.default "<NO CHANNEL>" file.channels)
     ~body `POST "files.upload" Slack_j.read_files_upload_res
 
+let www_form_of_get_upload_url_ext (req : Slack_t.get_upload_url_ext_req) =
+  let fields =
+    [
+      Some ("filename", req.filename);
+      Some ("length", Int.to_string req.length);
+      string_field_val req.alt_txt "alt_txt";
+      string_field_val req.snippet_type "snippet_type";
+    ]
+  in
+  list_filter_opt fields
+
+let get_upload_url_external ~(ctx : Context.t) ~(req : Slack_t.get_upload_url_ext_req) =
+  log#info "getting upload url for %s" req.filename;
+  let args = www_form_of_get_upload_url_ext req in
+  let data = Web.make_url_args args in
+  let body = `Raw ("application/x-www-form-urlencoded", data) in
+  log#info "data to upload req: %s" data;
+  request_token_auth ~ctx
+    ~name:(sprintf "files.getUploadURLExternal (%s)" req.filename)
+    ~body `POST "files.getUploadURLExternal" Slack_j.read_get_upload_url_ext_res
+
+let complete_upload_external ~(ctx : Context.t) ~(req : Slack_t.complete_upload_ext_req) =
+  log#info "completing upload url for %s" @@ Slack_j.string_of_files_v2 req.files;
+  let data = Slack_j.string_of_complete_upload_ext_req req in
+  let body = `Raw ("application/json", data) in
+  log#info "data to upload req: %s" data;
+  request_token_auth ~ctx
+    ~name:(sprintf "files.completeUploadExternal (%s)" @@ Slack_j.string_of_files_v2 req.files)
+    ~body `POST "files.completeUploadExternal" Slack_j.read_complete_upload_ext_res
+
+(** NOTE: this api only can specify one channel_id unlike in the deprecated version *)
+let upload_file_v2 ~(ctx : Context.t) ~(file : Slack_t.files_upload_req) =
+  match file.filename, file.content with
+  | None, _ | _, None -> Exn.fail "need to supply both filename and content"
+  | Some filename, Some content ->
+    let length = String.length content in
+    let req = Slack_j.make_get_upload_url_ext_req ~filename ~length () in
+    ( match%lwt get_upload_url_external ~ctx ~req with
+    | Error e -> Lwt.return_error e
+    | Ok { upload_url; file_id; _ } ->
+      let body = `Form [ "file", filename ] in
+      ( match%lwt http_request ~ua:ctx.ua ~body `POST upload_url with
+      | Error e -> slack_lib_fail "upload file failed with: %s" e
+      | Ok _ ->
+        let files : Slack_t.file_v2 = { id = file_id; title = file.title } in
+        let req =
+          Slack_j.make_complete_upload_ext_req ~files:[ files ] ?channel_id:file.channels ?thread_ts:file.thread_ts ()
+        in
+        ( match%lwt complete_upload_external ~ctx ~req with
+        | Error e -> Lwt.return_error e
+        | Ok { files; _ } ->
+          let f =
+            match files with
+            | [] -> slack_lib_fail "empty files on complete_upload_external response"
+            | [ f ] -> f
+            | f :: _ ->
+              log#warn "got more than 1 file in response, returning top";
+              f
+          in
+          Lwt.return_ok Slack_t.{ ok = true; file = Slack_j.make_file ~id:f.id ?title:f.title () }
+        )
+      )
+    )
+
 (** [join_conversation ctx channel ] will join the token owner
     [ctx.secrets.slack_access_token] to the [channel]. *)
 let join_conversation ~(ctx : Context.t) ~(channel : Slack_t.conversations_join_req) =

lib/slack.atd

@@ -130,7 +130,7 @@ type files_upload_req <ocaml attr="deriving make"> = {
   ?title: string nullable;
 }
 
-type file = {
+type file <ocaml attr="deriving make"> = {
   id: string;
   ?name: string nullable;
   ?title: string nullable;
@@ -151,6 +151,38 @@ type files_upload_res = {
   file: file;
 }
 
+type file_v2 = {
+  id: string;
+  ?title : string nullable
+}
+
+type files_v2 = file_v2 list
+
+type get_upload_url_ext_req <ocaml attr="deriving make"> = {
+  filename: string;
+  length: int;
+  ?alt_txt: string nullable;
+  ?snippet_type: string nullable
+}
+
+type get_upload_url_ext_res = {
+  ok: bool;
+  upload_url: string;
+  file_id: string
+}
+
+type complete_upload_ext_req <ocaml attr="deriving make"> = {
+  files: files_v2;
+  ?channel_id : string nullable;
+  ?initial_comment: string nullable;
+  ?thread_ts: string nullable
+}
+
+type complete_upload_ext_res = {
+  ok: bool;
+  files: files_v2;
+}
+
 type conversations_info_req <ocaml attr="deriving make"> = {
   channel: string;
   ?include_locale: bool nullable;