fix: rearrange all portals under common portal/ folder

7 files changed, 144 insertions, 0 deletions

diff --git a/portal/lib/dune b/portal/lib/dune
new file mode 100644
index 0000000..8ce0232
--- /dev/null
+++ b/portal/lib/dune
@@ -0,0 +1,6 @@
+(library
+ (name portal_ws)
+ (modules portal_ws)
+ (public_name flesh_websockets)
+ (libraries lwt js_of_ocaml js_of_ocaml-lwt xmlm)
+ (preprocess (pps js_of_ocaml-ppx)))
diff --git a/portal/lib/portal_ws.ml b/portal/lib/portal_ws.ml
new file mode 100644
index 0000000..1570a9e
--- /dev/null
+++ b/portal/lib/portal_ws.ml
@@ -0,0 +1,62 @@
+open Lwt.Syntax
+open Js_of_ocaml
+let jss = Js.string
+let sjs = Js.to_string
+
+(* sic. XEP-0156: "host-meta files MUST be fetched only over HTTPS". I don't make the rules. *)
+let well_known_of (domain : string) = "https://" ^ domain ^ "/.well-known/host-meta"
+
+let ws_endpoint (domain : string) =
+  (** [ws_endpoint domain] is a promise containing the XMPP websocket endpoint associated with [domain], by using the
+      domain's Web-host Metadata.
+
+      This function uses XMLHttpRequest, so while it should work fine in the browser, in environments that don't provide
+      this constructor (Node.js), there should be some sort of polyfill.
+
+      Lastly, if [domain] doesn't provide a well-formed Web-host Metadata file, the function throws an exception. *)
+
+  let+ host_meta = Js_of_ocaml_lwt.XmlHttpRequest.perform_raw_url (well_known_of domain)
+  in let i = Xmlm.make_input (`String (0, host_meta.content))
+     (* This ugly function extracts the href element from a Link tag's attributes if it's a websocket. *)
+     and link_websocket attrs =
+       match attrs with
+       | ((_, "href"), href) :: ((_, "rel"), "urn:xmpp:alt-connections:websocket") :: _ -> Some href
+       | ((_, "rel"), "urn:xmpp:alt-connections:websocket") :: ((_, "href"), href) :: _ -> Some href
+       | _ -> None
+     in let parse_tree = (* Parse a single XRD tree. *)
+          Xmlm.input_tree
+            ~el:(fun tag children
+                 -> match tag with
+                    | ((_, "Link"), attributes) -> link_websocket attributes
+                    | ((_, "XRD"), _) -> List.find_map (fun x -> x) children
+                    | _ -> None)
+            ~data:(fun x -> Some x)
+        in ignore (Xmlm.input i); (* DTD *)
+           match parse_tree i with
+           | Some uri -> uri
+           | None -> failwith (domain ^ "doesn't advertise a WebSocket endpoint via Web-host Metadata.")
+
+let ws_stream (url : string) =
+  (** [ws_stream url] returns a stream (and its push function) that talk with the websocket located at [url].
+
+      Pushing [None] closes the websocket.
+
+      If the websocket is closed server-side, it's still up to the caller to close the stream. *)
+  let open Lwt_stream in
+  let handle ws incoming () =
+    let+ _ = iter (fun msg -> ws##send (jss msg)) incoming
+    in (ws##close)
+  in let stream, message = create () (* websocket -> user *)
+     and incoming, push = create () (* user -> websocket *)
+     in let (ws : WebSockets.webSocket Js.t) = new%js WebSockets.webSocket (jss url)
+        in ws##.onmessage :=
+             Dom.handler (fun x -> Some (sjs x##.data) |> message; Js._false);
+           ws##.onopen :=
+             Dom.handler (fun _ -> Lwt.async @@ handle ws incoming; Js._false);
+           ws##.onclose :=
+             Dom.handler (fun _ -> message None; Js._true);
+           stream, push
+
+(* let connect domain = *)
+(*   let+ url = server_ws domain *)
+(*   in ws_stream url *)
diff --git a/portal/test/js/dune b/portal/test/js/dune
new file mode 100644
index 0000000..b34c980
--- /dev/null
+++ b/portal/test/js/dune
@@ -0,0 +1,14 @@
+(test
+ (name websockets_hello)
+ (libraries portal_ws lwt js_of_ocaml)
+ (modes js)
+ (preprocess (pps js_of_ocaml-ppx))
+ (deps node_modules)
+ (js_of_ocaml
+  (javascript_files polyfill.js)))
+
+(rule
+ (alias npm)
+ (target node_modules)
+ (deps package.json package-lock.json)
+ (action (system "npm ci")))
diff --git a/portal/test/js/package-lock.json b/portal/test/js/package-lock.json
new file mode 100644
index 0000000..8b5d148
--- /dev/null
+++ b/portal/test/js/package-lock.json
@@ -0,0 +1,21 @@
+{
+  "name": "js",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "dependencies": {
+        "xmlhttprequest": "^1.8.0"
+      }
+    },
+    "node_modules/xmlhttprequest": {
+      "version": "1.8.0",
+      "resolved": "https://registry.npmjs.org/xmlhttprequest/-/xmlhttprequest-1.8.0.tgz",
+      "integrity": "sha512-58Im/U0mlVBLM38NdZjHyhuMtCqa61469k2YP/AaPbvCoV9aQGUpbJBj1QRm2ytRiVQBD/fsw7L2bJGDVQswBA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=0.4.0"
+      }
+    }
+  }
+}
diff --git a/portal/test/js/package.json b/portal/test/js/package.json
new file mode 100644
index 0000000..3b36bf4
--- /dev/null
+++ b/portal/test/js/package.json
@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "xmlhttprequest": "^1.8.0"
+  }
+}
diff --git a/portal/test/js/polyfill.js b/portal/test/js/polyfill.js
new file mode 100644
index 0000000..e394ec8
--- /dev/null
+++ b/portal/test/js/polyfill.js
@@ -0,0 +1 @@
+global.XMLHttpRequest = require("xmlhttprequest").XMLHttpRequest;
diff --git a/portal/test/js/websockets_hello.ml b/portal/test/js/websockets_hello.ml
new file mode 100644
index 0000000..fa47965
--- /dev/null
+++ b/portal/test/js/websockets_hello.ml
@@ -0,0 +1,35 @@
+open Lwt.Syntax
+open Js_of_ocaml
+
+(* https://stackoverflow.com/questions/34929382/what-are-the-differences-between-lwt-async-and-lwt-main-run-on-ocaml-node-js *)
+let rec run t =
+  let next_tick (_callback : unit -> unit) =
+    Js.Unsafe.(fun_call
+                 (js_expr "process.nextTick")
+                 [| inject (Js.wrap_callback _callback) |])
+  in Lwt.wakeup_paused ();
+     match Lwt.poll t with
+     | Some x -> x
+     | None ->
+        if Lwt.paused_count () > 0
+        then next_tick (fun () -> run t)
+        else ()
+
+let () =
+  run @@
+    let* server = Portal_ws.ws_endpoint "telepath.im" in
+    let stream, push =
+      (* Echo is a websocket that... echoes you stuff. *)
+         Portal_ws.ws_stream "wss://echo.websocket.org" in
+       push (Some "great text");
+       push (Some "other text");
+       push (Some "yet another text");
+       push (Some "BYE");
+       let+ _ = Lwt_stream.iter
+               (fun greetings ->
+                 match greetings with
+                 (* When the websocket sends "BYE", we close. *)
+                 | "BYE" -> print_endline "CLOSING BYE"; push None
+                 | hello -> print_endline ("> " ^ hello))
+               stream
+       in print_endline server