new shrunk API for RNT on sakura

1 files changed, 40 insertions, 37 deletions

diff --git a/lib/session.ml b/lib/session.ml
index cac181f..ba4d96d 100644
--- a/lib/session.ml
+++ b/lib/session.ml
@@ -1,44 +1,47 @@
-(* Session: outermost connection object.
-   Each user connection mints a session registered in RNT at
-   /system/sessions/<id>. The session owns exactly one branch at a time;
-   DDL / DML / DRL sublanguages operate through that branch. *)
+type t = {identifier: string; branch: string; snapshot: string; commit: unit}
 
-module Make (NT : Nt.S) = struct
-  module B = Branch.Make (NT)
+let namespace identifier = "\\session\\" ^ identifier
+let branch_path name = "\\branch\\" ^ name
 
-  let ( let* ) = Result.bind
+let snapshot_of kernel branch =
+  let open Utilities.Result in
+  let* handle = RNT.lookup kernel (branch_path branch) in
+  let snapshot = RNT.identity handle in
+  RNT.release handle; Ok snapshot
 
-  class session ~(sid : string) ~(branch : B.branch) =
-    object
-      val mutable br : B.branch = branch
-      method id = sid
-      method branch = br
-      method snapshot = br#tip
-      method tip = br#tip
+class session ~kernel ~identifier ~branch ~snapshot ~commit =
+  object
+    val mutable session : t = {identifier; branch; snapshot; commit}
+    method identifier = session.identifier
+    method branch = session.branch
+    method snapshot = session.snapshot
+    method namespace = namespace session.identifier
 
-      (* Switch to a different branch within the same session. *)
-      method set_branch (b : B.branch) = br <- b
+    (** Switch to a different branch within the same session. *)
+    method set_branch_to branch =
+      let open Utilities.Result in
+      let* snapshot = snapshot_of kernel branch in
+      session <- {session with branch; snapshot};
+      Ok ()
 
-      method close () =
-        let* () = br#close () in
-        NT.session_close sid
-    end
+    method close = RNT.remove kernel (namespace session.identifier)
+  end
 
-  (* Open a session on a live (mutable) branch.
-     Creates the branch if it does not exist yet. *)
-  let open_session claims ~branch_name =
-    let* sid = NT.session_open () in
-    let* branch = B.open_branch claims branch_name in
-    Ok (new session ~sid ~branch)
+(* Open a session on a live (mutable) branch.
+   Creates the branch if it does not exist yet. *)
+let open_session kernel ~branch_name =
+  let open Utilities.Result in
+  let* branches = RNT.list kernel "\\branch" in
+  let* () =
+    if List.mem branch_name branches then Ok ()
+    else RNT.create kernel (branch_path branch_name) RNT.Branch
+  in
+  let* snapshot = snapshot_of kernel branch_name in
+  let identifier = Printf.sprintf "%016Lx" (Random.State.bits64 (Random.State.make_self_init ())) in
+  let* () = RNT.create kernel (namespace identifier) RNT.Namespace in
+  Ok (new session ~kernel ~identifier ~branch:branch_name ~snapshot ~commit:())
 
-  (* Open a session pinned to a specific snapshot hash (detached / read-only).
-     Mutations through the returned branch are refused. *)
-  let open_snapshot_session claims ~branch_name ~snapshot_hash =
-    let* sid = NT.session_open () in
-    let* branch = B.open_snapshot claims ~branch_name ~snapshot_hash in
-    (* Inform RNT of the session's snapshot override so future session-path
-       resolution (once NamespaceReferenceManager handles /system/sessions/...)
-       can route queries through the pinned snapshot. *)
-    let* () = NT.session_set_branch sid branch_name snapshot_hash in
-    Ok (new session ~sid ~branch)
-end
+(* Open a session pinned to a specific snapshot hash (detached / read-only).
+   Mutations through the returned branch are refused. *)
+(* let open_snapshot_session claims ~branch_name ~snapshot_hash = *)
+(* Error  *)