Merge pull request #20 from jestabro/vyconf-configsessionHEADmastercurrent

T7321: Replace legacy operations in configsession.py with vyconf client operations

10 files changed, 312 insertions, 117 deletions

diff --git a/src/session.ml b/src/session.ml
index 602ab14..24a8153 100644
--- a/src/session.ml
+++ b/src/session.ml
@@ -1,4 +1,5 @@
 module CT = Vyos1x.Config_tree
+module CD = Vyos1x.Config_diff
 module VT = Vyos1x.Vytree
 module RT = Vyos1x.Reference_tree
 module D = Directories
@@ -69,6 +70,21 @@ let validate w _s path =
         RT.validate_path D.(w.dirs.validators) w.reference_tree path
     with RT.Validation_error x -> raise (Session_error x)
 
+let validate_tree w' t =
+    let validate_path w out path =
+        let res =
+            try
+                RT.validate_path D.(w.dirs.validators) w.reference_tree path;
+                out
+            with RT.Validation_error x -> out ^ x
+        in res
+    in
+    let paths = CT.value_paths_of_tree t in
+    let out = List.fold_left (validate_path w') "" paths in
+    match out with
+    | "" -> ()
+    | _ -> raise (Session_error out)
+
 let split_path w _s path =
     RT.split_path w.reference_tree path
 
@@ -79,19 +95,47 @@ let set w s path =
     let value_behaviour = if RT.is_multi w.reference_tree refpath then CT.AddValue else CT.ReplaceValue in
     let op = CfgSet (path, value, value_behaviour) in
     let config =
-        apply_cfg_op op s.proposed_config |>
-        (fun c -> RT.set_tag_data w.reference_tree c path) |>
-        (fun c -> RT.set_leaf_data w.reference_tree c path)
+        try
+            apply_cfg_op op s.proposed_config |>
+            (fun c -> RT.set_tag_data w.reference_tree c path) |>
+            (fun c -> RT.set_leaf_data w.reference_tree c path)
+        with CT.Useless_set ->
+            raise (Session_error (Printf.sprintf "Useless set, path: %s" (string_of_op op)))
     in
     {s with proposed_config=config; changeset=(op :: s.changeset)}
 
 let delete w s path =
-    let _ = validate w s path in
     let path, value = split_path w s path in
     let op = CfgDelete (path, value) in
     let config = apply_cfg_op op s.proposed_config in
     {s with proposed_config=config; changeset=(op :: s.changeset)}
 
+let discard w s =
+    {s with proposed_config=w.running_config}
+
+let session_changed w s =
+    (* structural equality test requires consistent ordering, which is
+     * practised, but may be unreliable; test actual difference
+     *)
+    let diff = CD.diff_tree [] w.running_config s.proposed_config in
+    let add_tree = CT.get_subtree diff ["add"] in
+    let del_tree = CT.get_subtree diff ["del"] in
+    (del_tree <> CT.default) || (add_tree <> CT.default)
+
+let load w s file =
+    let ct = Vyos1x.Config_file.load_config file in
+    match ct with
+    | Error e -> raise (Session_error (Printf.sprintf "Error loading config: %s" e))
+    | Ok config ->
+        validate_tree w config; {s with proposed_config=config;}
+
+let save w s file =
+    let ct = w.running_config in
+    let res = Vyos1x.Config_file.save_config ct file in
+    match res with
+    | Error e -> raise (Session_error (Printf.sprintf "Error saving config: %s" e))
+    | Ok () -> s
+
 let get_value w s path =
     if not (VT.exists s.proposed_config path) then
         raise (Session_error ("Config path does not exist"))
diff --git a/src/session.mli b/src/session.mli
index 2166a80..9b8c5a0 100644
--- a/src/session.mli
+++ b/src/session.mli
@@ -32,6 +32,14 @@ val set : world -> session_data -> string list -> session_data
 
 val delete : world -> session_data -> string list -> session_data
 
+val discard : world -> session_data -> session_data
+
+val session_changed : world -> session_data -> bool
+
+val load : world -> session_data -> string -> session_data
+
+val save : world -> session_data -> string -> session_data
+
 val get_value : world -> session_data -> string list -> string
 
 val get_values : world -> session_data -> string list -> string list
diff --git a/src/startup.ml b/src/startup.ml
index 76599b0..20882cb 100644
--- a/src/startup.ml
+++ b/src/startup.ml
@@ -78,44 +78,16 @@ let create_server accept_connection sock =
         Lwt_unix.accept sock >>= accept_connection >>= serve
     in serve
 
-(* strip commponent version string *)
-let strip_version s =
-    let rex = Pcre.regexp ~flags:[`MULTILINE;`DOTALL] "(^//.*)" in
-    let res = Pcre.split ~max:0 ~rex s in
-    match res with
-    | h :: _ -> h
-    | [] -> panic "Failure applying regex to config string"
-
-(** Load the appliance configuration file *)
-let load_config file =
-    try
-        let chan = open_in file in
-        let s = really_input_string chan (in_channel_length chan) in
-        let config = strip_version s |> Vyos1x.Parser.from_string in
-        Ok config
-    with
-        | Sys_error msg -> Error msg
-        | Vyos1x.Util.Syntax_error (opt, msg) ->
-            begin
-                match opt with
-                | None ->
-                    let out = Printf.sprintf "Parse error: %s\n" msg
-                    in Error out
-                | Some (line, pos) ->
-                    let out = Printf.sprintf "Parse error: %s line %d pos %d\n" msg line pos
-                    in Error out
-            end
-
 (** Load the appliance configuration file or the fallback config *)
 let load_config_failsafe main fallback =
-    let res = load_config main in
+    let res = Vyos1x.Config_file.load_config main in
     match res with
     | Ok config -> config
     | Error msg -> 
         Lwt_log.error
           (Printf.sprintf "Failed to load config file %s: %s. Attempting to load fallback config %s" main msg fallback) |>
           Lwt.ignore_result;
-        let res = load_config fallback in
+        let res = Vyos1x.Config_file.load_config fallback in
         begin
             match res with
             | Ok config -> config
diff --git a/src/startup.mli b/src/startup.mli
index dc84736..1415953 100644
--- a/src/startup.mli
+++ b/src/startup.mli
@@ -14,8 +14,6 @@ val create_server :
     (Lwt_unix.file_descr * Lwt_unix.sockaddr -> unit Lwt.t) ->
     Lwt_unix.file_descr -> unit -> 'a Lwt.t
 
-val load_config : string -> (Vyos1x.Config_tree.t, string) result
-
 val load_config_failsafe : string -> string -> Vyos1x.Config_tree.t
 
 val load_interface_definitions : string -> (Vyos1x.Reference_tree.t, string) result
diff --git a/src/vycli.ml b/src/vycli.ml
index bd14713..75e92b5 100644
--- a/src/vycli.ml
+++ b/src/vycli.ml
@@ -2,7 +2,7 @@ open Vyconfd_client.Vyconf_client
 open Vyconf_connect.Vyconf_pbt
 
 type op_t =
-    | OpStatus
+    | OpPrompt
     | OpSetupSession
     | OpTeardownSession
     | OpShowConfig
@@ -35,7 +35,7 @@ let args = [
     ("--exists", Arg.Unit (fun () -> op := Some OpExists), "Check if specified path exists");
     ("--list-children", Arg.Unit (fun () -> op := Some OpListChildren), "List children of the node at the specified path");
     ("--show-config", Arg.Unit (fun () -> op := Some OpShowConfig), "Show the configuration at the specified path");
-    ("--status", Arg.Unit (fun () -> op := Some OpStatus), "Send a status/keepalive message");
+    ("--prompt", Arg.Unit (fun () -> op := Some OpPrompt), "Send a status/keepalive message");
     ("--validate", Arg.Unit (fun () -> op := Some OpValidate), "Validate path");
     ("--reload-reftree", Arg.Unit (fun () -> op := Some OpReloadReftree), "Reload reference tree");
    ]
@@ -59,8 +59,8 @@ let main socket op path out_format config_format =
     | Some o ->
         begin
             match o with
-            | OpStatus ->
-                let%lwt resp = get_status client in
+            | OpPrompt ->
+                let%lwt resp = prompt client in
                 begin
                     match resp.status with
                     | Success -> Ok "" |> Lwt.return
diff --git a/src/vyconf_client.ml b/src/vyconf_client.ml
index 7380760..c4811c5 100644
--- a/src/vyconf_client.ml
+++ b/src/vyconf_client.ml
@@ -48,8 +48,8 @@ let do_request client req =
     let%lwt resp = Vyconf_connect.Message.read client.ic in
     decode_pb_response (Pbrt.Decoder.of_bytes resp) |> Lwt.return
 
-let get_status client =
-    let req = Status in
+let prompt client =
+    let req = Prompt in
     let%lwt resp = do_request client req in
     Lwt.return resp
 
diff --git a/src/vyconf_client.mli b/src/vyconf_client.mli
index 5fd4df4..9c25c60 100644
--- a/src/vyconf_client.mli
+++ b/src/vyconf_client.mli
@@ -1,31 +1,12 @@
 type t
 
-type status =
-  | Success 
-  | Fail 
-  | Invalid_path 
-  | Invalid_value 
-  | Commit_in_progress 
-  | Configuration_locked 
-  | Internal_error 
-  | Permission_denied 
-  | Path_already_exists 
-
-type response = {
-  status : status;
-  output : string option;
-  error : string option;
-  warning : string option;
-}
-
-
 val create : ?token:(string option) -> string -> Vyconf_connect.Vyconf_pbt.request_output_format -> Vyconf_connect.Vyconf_pbt.request_config_format -> t Lwt.t
 
 val get_token : t -> (string, string) result Lwt.t
 
 val shutdown : t -> t Lwt.t
 
-val get_status : t -> response Lwt.t
+val prompt : t -> Vyconf_connect.Vyconf_pbt.response Lwt.t
 
 val setup_session : ?on_behalf_of:(int option) -> t -> string -> (t, string) result Lwt.t
 
diff --git a/src/vyconf_pbt.ml b/src/vyconf_pbt.ml
index 48a8e87..5518e27 100644
--- a/src/vyconf_pbt.ml
+++ b/src/vyconf_pbt.ml
@@ -8,7 +8,7 @@ type request_output_format =
   | Out_plain 
   | Out_json 
 
-type request_status = unit
+type request_prompt = unit
 
 type request_setup_session = {
   client_application : string option;
@@ -32,6 +32,14 @@ type request_delete = {
   path : string list;
 }
 
+type request_discard = {
+  dummy : int32 option;
+}
+
+type request_session_changed = {
+  dummy : int32 option;
+}
+
 type request_rename = {
   edit_level : string list;
   from : string;
@@ -118,7 +126,7 @@ type request_reload_reftree = {
 }
 
 type request =
-  | Status
+  | Prompt
   | Setup_session of request_setup_session
   | Set of request_set
   | Delete of request_delete
@@ -141,13 +149,16 @@ type request =
   | Validate of request_validate
   | Teardown of request_teardown
   | Reload_reftree of request_reload_reftree
+  | Load of request_load
+  | Discard of request_discard
+  | Session_changed of request_session_changed
 
 type request_envelope = {
   token : string option;
   request : request;
 }
 
-type status =
+type errnum =
   | Success 
   | Fail 
   | Invalid_path 
@@ -159,7 +170,7 @@ type status =
   | Path_already_exists 
 
 type response = {
-  status : status;
+  status : errnum;
   output : string option;
   error : string option;
   warning : string option;
@@ -169,7 +180,7 @@ let rec default_request_config_format () = (Curly:request_config_format)
 
 let rec default_request_output_format () = (Out_plain:request_output_format)
 
-let rec default_request_status = ()
+let rec default_request_prompt = ()
 
 let rec default_request_setup_session 
   ?client_application:((client_application:string option) = None)
@@ -205,6 +216,18 @@ let rec default_request_delete
   path;
 }
 
+let rec default_request_discard 
+  ?dummy:((dummy:int32 option) = None)
+  () : request_discard  = {
+  dummy;
+}
+
+let rec default_request_session_changed 
+  ?dummy:((dummy:int32 option) = None)
+  () : request_session_changed  = {
+  dummy;
+}
+
 let rec default_request_rename 
   ?edit_level:((edit_level:string list) = [])
   ?from:((from:string) = "")
@@ -339,7 +362,7 @@ let rec default_request_reload_reftree
   on_behalf_of;
 }
 
-let rec default_request (): request = Status
+let rec default_request (): request = Prompt
 
 let rec default_request_envelope 
   ?token:((token:string option) = None)
@@ -349,10 +372,10 @@ let rec default_request_envelope
   request;
 }
 
-let rec default_status () = (Success:status)
+let rec default_errnum () = (Success:errnum)
 
 let rec default_response 
-  ?status:((status:status) = default_status ())
+  ?status:((status:errnum) = default_errnum ())
   ?output:((output:string option) = None)
   ?error:((error:string option) = None)
   ?warning:((warning:string option) = None)
@@ -407,6 +430,22 @@ let default_request_delete_mutable () : request_delete_mutable = {
   path = [];
 }
 
+type request_discard_mutable = {
+  mutable dummy : int32 option;
+}
+
+let default_request_discard_mutable () : request_discard_mutable = {
+  dummy = None;
+}
+
+type request_session_changed_mutable = {
+  mutable dummy : int32 option;
+}
+
+let default_request_session_changed_mutable () : request_session_changed_mutable = {
+  dummy = None;
+}
+
 type request_rename_mutable = {
   mutable edit_level : string list;
   mutable from : string;
@@ -580,14 +619,14 @@ let default_request_envelope_mutable () : request_envelope_mutable = {
 }
 
 type response_mutable = {
-  mutable status : status;
+  mutable status : errnum;
   mutable output : string option;
   mutable error : string option;
   mutable warning : string option;
 }
 
 let default_response_mutable () : response_mutable = {
-  status = default_status ();
+  status = default_errnum ();
   output = None;
   error = None;
   warning = None;
@@ -607,7 +646,7 @@ let rec pp_request_output_format fmt (v:request_output_format) =
   | Out_plain -> Format.fprintf fmt "Out_plain"
   | Out_json -> Format.fprintf fmt "Out_json"
 
-let rec pp_request_status fmt (v:request_status) = 
+let rec pp_request_prompt fmt (v:request_prompt) = 
   let pp_i fmt () =
     Pbrt.Pp.pp_unit fmt ()
   in
@@ -645,6 +684,18 @@ let rec pp_request_delete fmt (v:request_delete) =
   in
   Pbrt.Pp.pp_brk pp_i fmt ()
 
+let rec pp_request_discard fmt (v:request_discard) = 
+  let pp_i fmt () =
+    Pbrt.Pp.pp_record_field ~first:true "dummy" (Pbrt.Pp.pp_option Pbrt.Pp.pp_int32) fmt v.dummy;
+  in
+  Pbrt.Pp.pp_brk pp_i fmt ()
+
+let rec pp_request_session_changed fmt (v:request_session_changed) = 
+  let pp_i fmt () =
+    Pbrt.Pp.pp_record_field ~first:true "dummy" (Pbrt.Pp.pp_option Pbrt.Pp.pp_int32) fmt v.dummy;
+  in
+  Pbrt.Pp.pp_brk pp_i fmt ()
+
 let rec pp_request_rename fmt (v:request_rename) = 
   let pp_i fmt () =
     Pbrt.Pp.pp_record_field ~first:true "edit_level" (Pbrt.Pp.pp_list Pbrt.Pp.pp_string) fmt v.edit_level;
@@ -772,7 +823,7 @@ let rec pp_request_reload_reftree fmt (v:request_reload_reftree) =
 
 let rec pp_request fmt (v:request) =
   match v with
-  | Status  -> Format.fprintf fmt "Status"
+  | Prompt  -> Format.fprintf fmt "Prompt"
   | Setup_session x -> Format.fprintf fmt "@[<hv2>Setup_session(@,%a)@]" pp_request_setup_session x
   | Set x -> Format.fprintf fmt "@[<hv2>Set(@,%a)@]" pp_request_set x
   | Delete x -> Format.fprintf fmt "@[<hv2>Delete(@,%a)@]" pp_request_delete x
@@ -795,6 +846,9 @@ let rec pp_request fmt (v:request) =
   | Validate x -> Format.fprintf fmt "@[<hv2>Validate(@,%a)@]" pp_request_validate x
   | Teardown x -> Format.fprintf fmt "@[<hv2>Teardown(@,%a)@]" pp_request_teardown x
   | Reload_reftree x -> Format.fprintf fmt "@[<hv2>Reload_reftree(@,%a)@]" pp_request_reload_reftree x
+  | Load x -> Format.fprintf fmt "@[<hv2>Load(@,%a)@]" pp_request_load x
+  | Discard x -> Format.fprintf fmt "@[<hv2>Discard(@,%a)@]" pp_request_discard x
+  | Session_changed x -> Format.fprintf fmt "@[<hv2>Session_changed(@,%a)@]" pp_request_session_changed x
 
 let rec pp_request_envelope fmt (v:request_envelope) = 
   let pp_i fmt () =
@@ -803,7 +857,7 @@ let rec pp_request_envelope fmt (v:request_envelope) =
   in
   Pbrt.Pp.pp_brk pp_i fmt ()
 
-let rec pp_status fmt (v:status) =
+let rec pp_errnum fmt (v:errnum) =
   match v with
   | Success -> Format.fprintf fmt "Success"
   | Fail -> Format.fprintf fmt "Fail"
@@ -817,7 +871,7 @@ let rec pp_status fmt (v:status) =
 
 let rec pp_response fmt (v:response) = 
   let pp_i fmt () =
-    Pbrt.Pp.pp_record_field ~first:true "status" pp_status fmt v.status;
+    Pbrt.Pp.pp_record_field ~first:true "status" pp_errnum fmt v.status;
     Pbrt.Pp.pp_record_field ~first:false "output" (Pbrt.Pp.pp_option Pbrt.Pp.pp_string) fmt v.output;
     Pbrt.Pp.pp_record_field ~first:false "error" (Pbrt.Pp.pp_option Pbrt.Pp.pp_string) fmt v.error;
     Pbrt.Pp.pp_record_field ~first:false "warning" (Pbrt.Pp.pp_option Pbrt.Pp.pp_string) fmt v.warning;
@@ -838,7 +892,7 @@ let rec encode_pb_request_output_format (v:request_output_format) encoder =
   | Out_plain -> Pbrt.Encoder.int_as_varint (0) encoder
   | Out_json -> Pbrt.Encoder.int_as_varint 1 encoder
 
-let rec encode_pb_request_status (v:request_status) encoder = 
+let rec encode_pb_request_prompt (v:request_prompt) encoder = 
 ()
 
 let rec encode_pb_request_setup_session (v:request_setup_session) encoder = 
@@ -892,6 +946,24 @@ let rec encode_pb_request_delete (v:request_delete) encoder =
   ) v.path encoder;
   ()
 
+let rec encode_pb_request_discard (v:request_discard) encoder = 
+  begin match v.dummy with
+  | Some x -> 
+    Pbrt.Encoder.int32_as_varint x encoder;
+    Pbrt.Encoder.key 1 Pbrt.Varint encoder; 
+  | None -> ();
+  end;
+  ()
+
+let rec encode_pb_request_session_changed (v:request_session_changed) encoder = 
+  begin match v.dummy with
+  | Some x -> 
+    Pbrt.Encoder.int32_as_varint x encoder;
+    Pbrt.Encoder.key 1 Pbrt.Varint encoder; 
+  | None -> ();
+  end;
+  ()
+
 let rec encode_pb_request_rename (v:request_rename) encoder = 
   Pbrt.List_util.rev_iter_with (fun x encoder -> 
     Pbrt.Encoder.string x encoder;
@@ -1084,7 +1156,7 @@ let rec encode_pb_request_reload_reftree (v:request_reload_reftree) encoder =
 
 let rec encode_pb_request (v:request) encoder = 
   begin match v with
-  | Status ->
+  | Prompt ->
     Pbrt.Encoder.key 1 Pbrt.Bytes encoder; 
     Pbrt.Encoder.empty_nested encoder
   | Setup_session x ->
@@ -1153,6 +1225,15 @@ let rec encode_pb_request (v:request) encoder =
   | Reload_reftree x ->
     Pbrt.Encoder.nested encode_pb_request_reload_reftree x encoder;
     Pbrt.Encoder.key 23 Pbrt.Bytes encoder; 
+  | Load x ->
+    Pbrt.Encoder.nested encode_pb_request_load x encoder;
+    Pbrt.Encoder.key 24 Pbrt.Bytes encoder; 
+  | Discard x ->
+    Pbrt.Encoder.nested encode_pb_request_discard x encoder;
+    Pbrt.Encoder.key 25 Pbrt.Bytes encoder; 
+  | Session_changed x ->
+    Pbrt.Encoder.nested encode_pb_request_session_changed x encoder;
+    Pbrt.Encoder.key 26 Pbrt.Bytes encoder; 
   end
 
 let rec encode_pb_request_envelope (v:request_envelope) encoder = 
@@ -1166,7 +1247,7 @@ let rec encode_pb_request_envelope (v:request_envelope) encoder =
   Pbrt.Encoder.key 2 Pbrt.Bytes encoder; 
   ()
 
-let rec encode_pb_status (v:status) encoder =
+let rec encode_pb_errnum (v:errnum) encoder =
   match v with
   | Success -> Pbrt.Encoder.int_as_varint (0) encoder
   | Fail -> Pbrt.Encoder.int_as_varint 1 encoder
@@ -1179,7 +1260,7 @@ let rec encode_pb_status (v:status) encoder =
   | Path_already_exists -> Pbrt.Encoder.int_as_varint 8 encoder
 
 let rec encode_pb_response (v:response) encoder = 
-  encode_pb_status v.status encoder;
+  encode_pb_errnum v.status encoder;
   Pbrt.Encoder.key 1 Pbrt.Varint encoder; 
   begin match v.output with
   | Some x -> 
@@ -1217,11 +1298,11 @@ let rec decode_pb_request_output_format d =
   | 1 -> (Out_json:request_output_format)
   | _ -> Pbrt.Decoder.malformed_variant "request_output_format"
 
-let rec decode_pb_request_status d =
+let rec decode_pb_request_prompt d =
   match Pbrt.Decoder.key d with
   | None -> ();
   | Some (_, pk) -> 
-    Pbrt.Decoder.unexpected_payload "Unexpected fields in empty message(request_status)" pk
+    Pbrt.Decoder.unexpected_payload "Unexpected fields in empty message(request_prompt)" pk
 
 let rec decode_pb_request_setup_session d =
   let v = default_request_setup_session_mutable () in
@@ -1328,6 +1409,42 @@ let rec decode_pb_request_delete d =
     path = v.path;
   } : request_delete)
 
+let rec decode_pb_request_discard d =
+  let v = default_request_discard_mutable () in
+  let continue__= ref true in
+  while !continue__ do
+    match Pbrt.Decoder.key d with
+    | None -> (
+    ); continue__ := false
+    | Some (1, Pbrt.Varint) -> begin
+      v.dummy <- Some (Pbrt.Decoder.int32_as_varint d);
+    end
+    | Some (1, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(request_discard), field(1)" pk
+    | Some (_, payload_kind) -> Pbrt.Decoder.skip d payload_kind
+  done;
+  ({
+    dummy = v.dummy;
+  } : request_discard)
+
+let rec decode_pb_request_session_changed d =
+  let v = default_request_session_changed_mutable () in
+  let continue__= ref true in
+  while !continue__ do
+    match Pbrt.Decoder.key d with
+    | None -> (
+    ); continue__ := false
+    | Some (1, Pbrt.Varint) -> begin
+      v.dummy <- Some (Pbrt.Decoder.int32_as_varint d);
+    end
+    | Some (1, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(request_session_changed), field(1)" pk
+    | Some (_, payload_kind) -> Pbrt.Decoder.skip d payload_kind
+  done;
+  ({
+    dummy = v.dummy;
+  } : request_session_changed)
+
 let rec decode_pb_request_rename d =
   let v = default_request_rename_mutable () in
   let continue__= ref true in
@@ -1767,7 +1884,7 @@ let rec decode_pb_request d =
       | None -> Pbrt.Decoder.malformed_variant "request"
       | Some (1, _) -> begin 
         Pbrt.Decoder.empty_nested d ;
-        (Status : request)
+        (Prompt : request)
       end
       | Some (2, _) -> (Setup_session (decode_pb_request_setup_session (Pbrt.Decoder.nested d)) : request) 
       | Some (3, _) -> (Set (decode_pb_request_set (Pbrt.Decoder.nested d)) : request) 
@@ -1797,6 +1914,9 @@ let rec decode_pb_request d =
       | Some (21, _) -> (Validate (decode_pb_request_validate (Pbrt.Decoder.nested d)) : request) 
       | Some (22, _) -> (Teardown (decode_pb_request_teardown (Pbrt.Decoder.nested d)) : request) 
       | Some (23, _) -> (Reload_reftree (decode_pb_request_reload_reftree (Pbrt.Decoder.nested d)) : request) 
+      | Some (24, _) -> (Load (decode_pb_request_load (Pbrt.Decoder.nested d)) : request) 
+      | Some (25, _) -> (Discard (decode_pb_request_discard (Pbrt.Decoder.nested d)) : request) 
+      | Some (26, _) -> (Session_changed (decode_pb_request_session_changed (Pbrt.Decoder.nested d)) : request) 
       | Some (n, payload_kind) -> (
         Pbrt.Decoder.skip d payload_kind; 
         loop () 
@@ -1832,18 +1952,18 @@ let rec decode_pb_request_envelope d =
     request = v.request;
   } : request_envelope)
 
-let rec decode_pb_status d = 
+let rec decode_pb_errnum d = 
   match Pbrt.Decoder.int_as_varint d with
-  | 0 -> (Success:status)
-  | 1 -> (Fail:status)
-  | 2 -> (Invalid_path:status)
-  | 3 -> (Invalid_value:status)
-  | 4 -> (Commit_in_progress:status)
-  | 5 -> (Configuration_locked:status)
-  | 6 -> (Internal_error:status)
-  | 7 -> (Permission_denied:status)
-  | 8 -> (Path_already_exists:status)
-  | _ -> Pbrt.Decoder.malformed_variant "status"
+  | 0 -> (Success:errnum)
+  | 1 -> (Fail:errnum)
+  | 2 -> (Invalid_path:errnum)
+  | 3 -> (Invalid_value:errnum)
+  | 4 -> (Commit_in_progress:errnum)
+  | 5 -> (Configuration_locked:errnum)
+  | 6 -> (Internal_error:errnum)
+  | 7 -> (Permission_denied:errnum)
+  | 8 -> (Path_already_exists:errnum)
+  | _ -> Pbrt.Decoder.malformed_variant "errnum"
 
 let rec decode_pb_response d =
   let v = default_response_mutable () in
@@ -1854,7 +1974,7 @@ let rec decode_pb_response d =
     | None -> (
     ); continue__ := false
     | Some (1, Pbrt.Varint) -> begin
-      v.status <- decode_pb_status d; status_is_set := true;
+      v.status <- decode_pb_errnum d; status_is_set := true;
     end
     | Some (1, pk) -> 
       Pbrt.Decoder.unexpected_payload "Message(response), field(1)" pk
diff --git a/src/vyconf_pbt.mli b/src/vyconf_pbt.mli
index 7189a7a..5f768f8 100644
--- a/src/vyconf_pbt.mli
+++ b/src/vyconf_pbt.mli
@@ -15,7 +15,7 @@ type request_output_format =
   | Out_plain 
   | Out_json 
 
-type request_status = unit
+type request_prompt = unit
 
 type request_setup_session = {
   client_application : string option;
@@ -39,6 +39,14 @@ type request_delete = {
   path : string list;
 }
 
+type request_discard = {
+  dummy : int32 option;
+}
+
+type request_session_changed = {
+  dummy : int32 option;
+}
+
 type request_rename = {
   edit_level : string list;
   from : string;
@@ -125,7 +133,7 @@ type request_reload_reftree = {
 }
 
 type request =
-  | Status
+  | Prompt
   | Setup_session of request_setup_session
   | Set of request_set
   | Delete of request_delete
@@ -148,13 +156,16 @@ type request =
   | Validate of request_validate
   | Teardown of request_teardown
   | Reload_reftree of request_reload_reftree
+  | Load of request_load
+  | Discard of request_discard
+  | Session_changed of request_session_changed
 
 type request_envelope = {
   token : string option;
   request : request;
 }
 
-type status =
+type errnum =
   | Success 
   | Fail 
   | Invalid_path 
@@ -166,7 +177,7 @@ type status =
   | Path_already_exists 
 
 type response = {
-  status : status;
+  status : errnum;
   output : string option;
   error : string option;
   warning : string option;
@@ -181,8 +192,8 @@ val default_request_config_format : unit -> request_config_format
 val default_request_output_format : unit -> request_output_format
 (** [default_request_output_format ()] is the default value for type [request_output_format] *)
 
-val default_request_status : unit
-(** [default_request_status ()] is the default value for type [request_status] *)
+val default_request_prompt : unit
+(** [default_request_prompt ()] is the default value for type [request_prompt] *)
 
 val default_request_setup_session : 
   ?client_application:string option ->
@@ -216,6 +227,18 @@ val default_request_delete :
   request_delete
 (** [default_request_delete ()] is the default value for type [request_delete] *)
 
+val default_request_discard : 
+  ?dummy:int32 option ->
+  unit ->
+  request_discard
+(** [default_request_discard ()] is the default value for type [request_discard] *)
+
+val default_request_session_changed : 
+  ?dummy:int32 option ->
+  unit ->
+  request_session_changed
+(** [default_request_session_changed ()] is the default value for type [request_session_changed] *)
+
 val default_request_rename : 
   ?edit_level:string list ->
   ?from:string ->
@@ -345,11 +368,11 @@ val default_request_envelope :
   request_envelope
 (** [default_request_envelope ()] is the default value for type [request_envelope] *)
 
-val default_status : unit -> status
-(** [default_status ()] is the default value for type [status] *)
+val default_errnum : unit -> errnum
+(** [default_errnum ()] is the default value for type [errnum] *)
 
 val default_response : 
-  ?status:status ->
+  ?status:errnum ->
   ?output:string option ->
   ?error:string option ->
   ?warning:string option ->
@@ -366,8 +389,8 @@ val pp_request_config_format : Format.formatter -> request_config_format -> unit
 val pp_request_output_format : Format.formatter -> request_output_format -> unit 
 (** [pp_request_output_format v] formats v *)
 
-val pp_request_status : Format.formatter -> request_status -> unit 
-(** [pp_request_status v] formats v *)
+val pp_request_prompt : Format.formatter -> request_prompt -> unit 
+(** [pp_request_prompt v] formats v *)
 
 val pp_request_setup_session : Format.formatter -> request_setup_session -> unit 
 (** [pp_request_setup_session v] formats v *)
@@ -384,6 +407,12 @@ val pp_request_set : Format.formatter -> request_set -> unit
 val pp_request_delete : Format.formatter -> request_delete -> unit 
 (** [pp_request_delete v] formats v *)
 
+val pp_request_discard : Format.formatter -> request_discard -> unit 
+(** [pp_request_discard v] formats v *)
+
+val pp_request_session_changed : Format.formatter -> request_session_changed -> unit 
+(** [pp_request_session_changed v] formats v *)
+
 val pp_request_rename : Format.formatter -> request_rename -> unit 
 (** [pp_request_rename v] formats v *)
 
@@ -444,8 +473,8 @@ val pp_request : Format.formatter -> request -> unit
 val pp_request_envelope : Format.formatter -> request_envelope -> unit 
 (** [pp_request_envelope v] formats v *)
 
-val pp_status : Format.formatter -> status -> unit 
-(** [pp_status v] formats v *)
+val pp_errnum : Format.formatter -> errnum -> unit 
+(** [pp_errnum v] formats v *)
 
 val pp_response : Format.formatter -> response -> unit 
 (** [pp_response v] formats v *)
@@ -459,8 +488,8 @@ val encode_pb_request_config_format : request_config_format -> Pbrt.Encoder.t ->
 val encode_pb_request_output_format : request_output_format -> Pbrt.Encoder.t -> unit
 (** [encode_pb_request_output_format v encoder] encodes [v] with the given [encoder] *)
 
-val encode_pb_request_status : request_status -> Pbrt.Encoder.t -> unit
-(** [encode_pb_request_status v encoder] encodes [v] with the given [encoder] *)
+val encode_pb_request_prompt : request_prompt -> Pbrt.Encoder.t -> unit
+(** [encode_pb_request_prompt v encoder] encodes [v] with the given [encoder] *)
 
 val encode_pb_request_setup_session : request_setup_session -> Pbrt.Encoder.t -> unit
 (** [encode_pb_request_setup_session v encoder] encodes [v] with the given [encoder] *)
@@ -477,6 +506,12 @@ val encode_pb_request_set : request_set -> Pbrt.Encoder.t -> unit
 val encode_pb_request_delete : request_delete -> Pbrt.Encoder.t -> unit
 (** [encode_pb_request_delete v encoder] encodes [v] with the given [encoder] *)
 
+val encode_pb_request_discard : request_discard -> Pbrt.Encoder.t -> unit
+(** [encode_pb_request_discard v encoder] encodes [v] with the given [encoder] *)
+
+val encode_pb_request_session_changed : request_session_changed -> Pbrt.Encoder.t -> unit
+(** [encode_pb_request_session_changed v encoder] encodes [v] with the given [encoder] *)
+
 val encode_pb_request_rename : request_rename -> Pbrt.Encoder.t -> unit
 (** [encode_pb_request_rename v encoder] encodes [v] with the given [encoder] *)
 
@@ -537,8 +572,8 @@ val encode_pb_request : request -> Pbrt.Encoder.t -> unit
 val encode_pb_request_envelope : request_envelope -> Pbrt.Encoder.t -> unit
 (** [encode_pb_request_envelope v encoder] encodes [v] with the given [encoder] *)
 
-val encode_pb_status : status -> Pbrt.Encoder.t -> unit
-(** [encode_pb_status v encoder] encodes [v] with the given [encoder] *)
+val encode_pb_errnum : errnum -> Pbrt.Encoder.t -> unit
+(** [encode_pb_errnum v encoder] encodes [v] with the given [encoder] *)
 
 val encode_pb_response : response -> Pbrt.Encoder.t -> unit
 (** [encode_pb_response v encoder] encodes [v] with the given [encoder] *)
@@ -552,8 +587,8 @@ val decode_pb_request_config_format : Pbrt.Decoder.t -> request_config_format
 val decode_pb_request_output_format : Pbrt.Decoder.t -> request_output_format
 (** [decode_pb_request_output_format decoder] decodes a [request_output_format] binary value from [decoder] *)
 
-val decode_pb_request_status : Pbrt.Decoder.t -> request_status
-(** [decode_pb_request_status decoder] decodes a [request_status] binary value from [decoder] *)
+val decode_pb_request_prompt : Pbrt.Decoder.t -> request_prompt
+(** [decode_pb_request_prompt decoder] decodes a [request_prompt] binary value from [decoder] *)
 
 val decode_pb_request_setup_session : Pbrt.Decoder.t -> request_setup_session
 (** [decode_pb_request_setup_session decoder] decodes a [request_setup_session] binary value from [decoder] *)
@@ -570,6 +605,12 @@ val decode_pb_request_set : Pbrt.Decoder.t -> request_set
 val decode_pb_request_delete : Pbrt.Decoder.t -> request_delete
 (** [decode_pb_request_delete decoder] decodes a [request_delete] binary value from [decoder] *)
 
+val decode_pb_request_discard : Pbrt.Decoder.t -> request_discard
+(** [decode_pb_request_discard decoder] decodes a [request_discard] binary value from [decoder] *)
+
+val decode_pb_request_session_changed : Pbrt.Decoder.t -> request_session_changed
+(** [decode_pb_request_session_changed decoder] decodes a [request_session_changed] binary value from [decoder] *)
+
 val decode_pb_request_rename : Pbrt.Decoder.t -> request_rename
 (** [decode_pb_request_rename decoder] decodes a [request_rename] binary value from [decoder] *)
 
@@ -630,8 +671,8 @@ val decode_pb_request : Pbrt.Decoder.t -> request
 val decode_pb_request_envelope : Pbrt.Decoder.t -> request_envelope
 (** [decode_pb_request_envelope decoder] decodes a [request_envelope] binary value from [decoder] *)
 
-val decode_pb_status : Pbrt.Decoder.t -> status
-(** [decode_pb_status decoder] decodes a [status] binary value from [decoder] *)
+val decode_pb_errnum : Pbrt.Decoder.t -> errnum
+(** [decode_pb_errnum decoder] decodes a [errnum] binary value from [decoder] *)
 
 val decode_pb_response : Pbrt.Decoder.t -> response
 (** [decode_pb_response decoder] decodes a [response] binary value from [decoder] *)
diff --git a/src/vyconfd.ml b/src/vyconfd.ml
index fc47bf6..885fd20 100644
--- a/src/vyconfd.ml
+++ b/src/vyconfd.ml
@@ -95,6 +95,10 @@ let teardown token =
     with Not_found ->
         {response_tmpl with status=Fail; error=(Some "Session not found")}
 
+let session_changed world token (_req: request_session_changed) =
+    if Session.session_changed world (find_session token) then response_tmpl
+    else {response_tmpl with status=Fail}
+
 let exists world token (req: request_exists) =
     if Session.exists world (find_session token) req.path then response_tmpl
     else {response_tmpl with status=Fail}
@@ -163,6 +167,29 @@ let delete world token (req: request_delete) =
         response_tmpl
     with Session.Session_error msg -> {response_tmpl with status=Fail; error=(Some msg)}
 
+let discard world token (_req: request_discard) =
+    try
+        let session = Session.discard world (find_session token)
+        in
+        Hashtbl.replace sessions token session;
+        response_tmpl
+    with Session.Session_error msg -> {response_tmpl with status=Fail; error=(Some msg)}
+
+let load world token (req: request_load) =
+    try
+        let session = Session.load world (find_session token) req.location
+        in
+        Hashtbl.replace sessions token session;
+        response_tmpl
+    with Session.Session_error msg -> {response_tmpl with status=Fail; error=(Some msg)}
+
+let save world token (req: request_save) =
+    try
+        let _ = Session.save world (find_session token) req.location
+        in
+        response_tmpl
+    with Session.Session_error msg -> {response_tmpl with status=Fail; error=(Some msg)}
+
 let commit world token (req: request_commit) =
     let s = find_session token in
     let at = world.Session.running_config in
@@ -236,7 +263,7 @@ let rec handle_connection world ic oc () =
                | _ as req ->
                begin
                     (match req with
-                    | _, Status -> response_tmpl
+                    | _, Prompt -> response_tmpl
                     | _, Setup_session r -> setup_session world r
                     | _, Reload_reftree r -> reload_reftree world r
                     | None, _ -> {response_tmpl with status=Fail; output=(Some "Operation requires session token")}
@@ -251,6 +278,10 @@ let rec handle_connection world ic oc () =
                     | Some t, Validate r -> validate world t r
                     | Some t, Set r -> set world t r
                     | Some t, Delete r -> delete world t r
+                    | Some t, Discard r -> discard world t r
+                    | Some t, Session_changed r -> session_changed world t r
+                    | Some t, Load r -> load world t r
+                    | Some t, Save r -> save world t r
                     | _ -> failwith "Unimplemented"
                     ) |> Lwt.return
                end