Merge pull request #15 from jestabro/commitdHEADmaster

T7121: Set up communication vyconfd to vyos-commitd

12 files changed, 754 insertions, 29 deletions

diff --git a/data/dune b/data/dune
index e5ffaa6..df63152 100644
--- a/data/dune
+++ b/data/dune
@@ -1,3 +1,3 @@
 (install
- (files vyconfd.conf vyconf.proto)
+ (files vyconfd.conf vyconf.proto vycall.proto)
  (section share))
diff --git a/data/vycall.proto b/data/vycall.proto
new file mode 100644
index 0000000..e0af67b
--- /dev/null
+++ b/data/vycall.proto
@@ -0,0 +1,27 @@
+message Status {
+    required bool success = 1;
+    required string out = 2;
+}
+
+message Call {
+    required string script_name = 1;
+    optional string tag_value = 2;
+    optional string arg_value = 3;
+    optional Status reply = 4;
+}
+
+message Commit {
+    required string session_id = 1;
+    // optional explicit load;
+    // otherwise, session configs are loaded from cached internal
+    // representation, specified by session id value
+    optional string named_active = 2;
+    optional string named_proposed = 3;
+    //
+    required bool dry_run = 4;
+    required bool atomic = 5;
+    required bool background = 6;
+
+    optional Status init = 7;
+    repeated Call calls = 8;
+}
diff --git a/data/vyconfd.conf b/data/vyconfd.conf
index bcde860..d1ae247 100644
--- a/data/vyconfd.conf
+++ b/data/vyconfd.conf
@@ -6,6 +6,7 @@ data_dir = "/usr/share/vyos/vyconf"
 program_dir = "/usr/libexec/vyos"
 config_dir = "/usr/libexec/vyos/vyconf/config"
 reftree_dir = "/usr/libexec/vyos/vyconf/reftree"
+session_dir = "/usr/libexec/vyos/vyconf/session"
 
 # paths relative to config_dir
 primary_config = "config.boot"
@@ -14,6 +15,12 @@ fallback_config = "config.failsafe"
 # paths relative to reftree_dir
 reference_tree = "reftree.cache"
 
+# paths relative to session_dir
+running_cache = "running_cache"
+session_cache = "session_cache"
+
+commitd_socket = "/var/run/vyos-commitd.sock"
+
 [vyconf]
 
 socket = "/var/run/vyconfd.sock"
diff --git a/src/commit.ml b/src/commit.ml
index 3c593fd..a2b9f6e 100644
--- a/src/commit.ml
+++ b/src/commit.ml
@@ -4,21 +4,58 @@ module CD = Vyos1x.Config_diff
 module RT = Vyos1x.Reference_tree
 module FP = FilePath
 
-type commit_data = {
-    script: string option;
+type tree_source = DELETE | ADD
+
+let tree_source_to_yojson = function
+    | DELETE -> `String "DELETE"
+    | ADD -> `String "ADD"
+
+type status = {
+  success : bool;
+  out : string;
+} [@@deriving to_yojson]
+
+type node_data = {
+    script_name: string;
     priority: int;
     tag_value: string option;
     arg_value: string option;
     path: string list;
-} [@@deriving yojson]
+    source: tree_source;
+    reply: status option;
+} [@@deriving to_yojson]
 
 
-let default_commit_data = {
-    script = None;
+let default_node_data = {
+    script_name = "";
     priority = 0;
     tag_value = None;
     arg_value = None;
     path = [];
+    source = ADD;
+    reply = Some { success = false; out = ""; };
+}
+
+type commit_data = {
+    session_id: string;
+    named_active : string option;
+    named_proposed : string option;
+    dry_run: bool;
+    atomic: bool;
+    background: bool;
+    init: status option;
+    node_list: node_data list;
+} [@@deriving to_yojson]
+
+let default_commit_data = {
+    session_id = "";
+    named_active = None;
+    named_proposed = None;
+    dry_run = false;
+    atomic = false;
+    background = false;
+    init = Some { success = false; out = ""; };
+    node_list = [];
 }
 
 let lex_order c1 c2 =
@@ -33,7 +70,7 @@ let lex_order c1 c2 =
     | _ as a -> a
 
 module CI = struct
-    type t = commit_data
+    type t = node_data
     let compare a b =
         match compare a.priority b.priority with
         | 0 -> lex_order a b
@@ -41,24 +78,21 @@ module CI = struct
 end
 module CS = Set.Make(CI)
 
-let owner_args_from_data p s =
-    match s with
-    | None -> None, None
-    | Some o ->
+let owner_args_from_data p o =
     let oa = Pcre.split o in
     let owner = FilePath.basename (List.nth oa 0) in
-    if List.length oa < 2 then Some owner, None
+    if List.length oa < 2 then owner, None
     else
     let var = List.nth oa 1 in
     let res = Pcre.extract_all ~pat:"\\.\\./" var in
     let var_pos = Array.length res in
     let arg_value = Vyos1x.Util.get_last_n p var_pos
-    in Some owner, arg_value
+    in owner, arg_value
 
 let add_tag_instance cd cs tv =
     CS.add { cd with tag_value = Some tv; } cs
 
-let get_commit_data rt ct (path, cs') t =
+let get_node_data rt ct src (path, cs') t =
     if Vyos1x.Util.is_empty path then
         (path, cs')
     else
@@ -78,14 +112,16 @@ let get_commit_data rt ct (path, cs') t =
         | Some s -> int_of_string s
     in
     let owner = RT.get_owner rt rt_path in
-    if  owner = None then (path, cs')
-    else
-    let (own, arg) = owner_args_from_data rpath owner in
-    let c_data = { default_commit_data with
-                   script = own;
+    match owner with
+    | None -> (path, cs')
+    | Some owner_str ->
+    let (own, arg) = owner_args_from_data rpath owner_str in
+    let c_data = { default_node_data with
+                   script_name = own;
                    priority = priority;
                    arg_value = arg;
-                   path = rpath; }
+                   path = rpath;
+                   source = src; }
     in
     let tag_values =
         match RT.is_tag rt rt_path with
@@ -98,8 +134,8 @@ let get_commit_data rt ct (path, cs') t =
         | _ -> List.fold_left (add_tag_instance c_data) cs' tag_values
     in (path, cs)
 
-let get_commit_set rt ct =
-    snd (VT.fold_tree_with_path (get_commit_data rt ct) ([], CS.empty) ct)
+let get_commit_set rt ct src =
+    snd (VT.fold_tree_with_path (get_node_data rt ct src) ([], CS.empty) ct)
 
 (* for initial consistency with the legacy ordering of delete and add
    queues, enforce the following subtlety: if a path in the delete tree is
@@ -123,11 +159,23 @@ let calculate_priority_lists rt at wt =
     let diff = CD.diff_tree [] at wt in
     let del_tree = CD.get_tagged_delete_tree diff in
     let add_tree = CT.get_subtree diff ["add"] in
-    let cs_del' = get_commit_set rt del_tree in
-    let cs_add' = get_commit_set rt add_tree in
+    let cs_del' = get_commit_set rt del_tree DELETE in
+    let cs_add' = get_commit_set rt add_tree ADD in
     let cs_del, cs_add = legacy_order del_tree cs_del' cs_add' in
     List.rev (CS.elements cs_del), CS.elements cs_add
 
+let commit_store c_data =
+    let out =
+        let func acc nd =
+            match nd.reply with
+            | None -> acc ^ "\n"
+            | Some r ->
+                match r.success with
+                | true -> acc ^ "\n"
+                | false -> acc ^ "\n" ^ r.out
+        in List.fold_left func "" c_data.node_list
+    in print_endline out
+
 let show_commit_data at wt =
     let vc =
         Startup.load_daemon_config Defaults.defaults.config_file in
@@ -140,9 +188,9 @@ let show_commit_data at wt =
         let del_list, add_list =
             calculate_priority_lists rt at wt
         in
-        let sprint_commit_data acc s =
-            acc ^ "\n" ^ (commit_data_to_yojson s |> Yojson.Safe.to_string)
+        let sprint_node_data acc s =
+            acc ^ "\n" ^ (node_data_to_yojson s |> Yojson.Safe.to_string)
         in
-        let del_out = List.fold_left sprint_commit_data "" del_list in
-        let add_out = List.fold_left sprint_commit_data "" add_list in
+        let del_out = List.fold_left sprint_node_data "" del_list in
+        let add_out = List.fold_left sprint_node_data "" add_list in
         del_out ^ "\n" ^ add_out
diff --git a/src/commit.mli b/src/commit.mli
index db91195..da97389 100644
--- a/src/commit.mli
+++ b/src/commit.mli
@@ -1,2 +1,37 @@
+type tree_source = DELETE | ADD
+
+type status = {
+  success : bool;
+  out : string;
+}
+
+type node_data = {
+    script_name: string;
+    priority: int;
+    tag_value: string option;
+    arg_value: string option;
+    path: string list;
+    source: tree_source;
+    reply: status option;
+} [@@deriving to_yojson]
+
+type commit_data = {
+    session_id: string;
+    named_active : string option;
+    named_proposed : string option;
+    dry_run: bool;
+    atomic: bool;
+    background: bool;
+    init: status option;
+    node_list: node_data list;
+} [@@deriving to_yojson]
+
+val default_node_data : node_data
+
+val default_commit_data : commit_data
+
+val calculate_priority_lists : Vyos1x.Reference_tree.t -> Vyos1x.Config_tree.t -> Vyos1x.Config_tree.t -> node_data list * node_data list
+
+val commit_store : commit_data -> unit
 
 val show_commit_data : Vyos1x.Config_tree.t -> Vyos1x.Config_tree.t -> string
diff --git a/src/dune b/src/dune
index 3998f1e..5e08579 100644
--- a/src/dune
+++ b/src/dune
@@ -22,6 +22,19 @@
             yojson ppx_deriving.show ppx_deriving_yojson)
  (preprocess (pps lwt_ppx ppx_deriving.show ppx_deriving_yojson)))
 
+(library
+ (name vycall_message)
+ (public_name vyconf.vycall-message)
+ (modules vycall_pbt)
+ (libraries ocaml-protoc))
+
+(library
+ (name commitd_client)
+ (public_name vyconf.vycall-client)
+ (modules vycall_client)
+ (libraries vyos1x-config vyconfd_config vycall_message lwt lwt.unix lwt_log lwt_ppx ocplib-endian)
+ (preprocess (pps lwt_ppx)))
+
 (executable
  (name vyconfd)
  (public_name vyconfd)
@@ -50,7 +63,6 @@
  (preprocess (pps lwt_ppx)))
 
 (rule
- (alias protoc)
  (mode promote)
  (targets vyconf_pbt.ml vyconf_pbt.mli)
  (action
@@ -61,6 +73,17 @@
     (run mv src/vyconf.ml src/vyconf_pbt.ml)
     (run mv src/vyconf.mli src/vyconf_pbt.mli)))))
 
+(rule
+ (mode promote)
+ (targets vycall_pbt.ml vycall_pbt.mli)
+ (action
+  (chdir
+   %{project_root}
+   (progn
+    (run ocaml-protoc --ml_out src data/vycall.proto)
+    (run mv src/vycall.ml src/vycall_pbt.ml)
+    (run mv src/vycall.mli src/vycall_pbt.mli)))))
+
 (library
  (name vyos1x_adapter)
  (public_name vyconf.vyos1x-adapter)
diff --git a/src/vycall_client.ml b/src/vycall_client.ml
new file mode 100644
index 0000000..c7fc811
--- /dev/null
+++ b/src/vycall_client.ml
@@ -0,0 +1,124 @@
+(* send commit data to Python commit daemon *)
+
+open Vycall_message.Vycall_pbt
+open Vyconfd_config.Commit
+
+module CT = Vyos1x.Config_tree
+module IC = Vyos1x.Internal.Make(CT)
+module ST = Vyconfd_config.Startup
+module DF = Vyconfd_config.Defaults
+module FP = FilePath
+
+type t = {
+    ic: Lwt_io.input Lwt_io.channel;
+    oc: Lwt_io.output Lwt_io.channel;
+}
+
+(* explicit translation between commit data and commit protobuf
+ * to keep the commit data opaque to protobuf message definition.
+ * The commit daemon updates the (subset of) commit data with
+ * results of script execution in init/reply fields.
+ *)
+let node_data_to_call nd =
+    { script_name = nd.script_name;
+      tag_value = nd.tag_value;
+      arg_value = nd.arg_value;
+      reply = None
+    }
+
+let call_to_node_data ((c: call), (nd: node_data)) =
+    match c.reply with
+    | None -> nd
+    | Some r -> { nd with reply = Some { success = r.success; out = r.out }}
+
+let commit_data_to_commit_proto cd =
+    { session_id = cd.session_id;
+      named_active = cd.named_active;
+      named_proposed = cd.named_proposed;
+      dry_run = cd.dry_run;
+      atomic = cd.atomic;
+      background = cd.background;
+      init = None;
+      calls = List.map node_data_to_call cd.node_list;
+    }
+
+let commit_proto_to_commit_data (c: commit) (cd: commit_data) =
+    match c.init with
+    | None -> cd
+    | Some i ->
+        { cd with init = Some { success = i.success; out = i.out };
+          node_list =
+              List.map call_to_node_data (List.combine c.calls cd.node_list);
+        }
+
+(* read/write message from/to socket *)
+let call_write oc msg =
+    let length = Bytes.length msg in
+    let length' = Int32.of_int length in
+    if length' < 0l then failwith (Printf.sprintf "Bad message length: %d" length) else
+    let header = Bytes.create 4 in
+    let () = EndianBytes.BigEndian.set_int32 header 0 length' in
+    let%lwt () = Lwt_io.write_from_exactly oc header 0 4 in
+    Lwt_io.write_from_exactly oc msg 0 length
+
+let call_read ic =
+    let header = Bytes.create 4 in
+    let%lwt () = Lwt_io.read_into_exactly ic header 0 4 in
+    let length = EndianBytes.BigEndian.get_int32 header 0 |> Int32.to_int in
+    if length < 0 then failwith (Printf.sprintf "Bad message length: %d" length) else
+    let buffer = Bytes.create length in
+    let%lwt () = Lwt_io.read_into_exactly ic buffer 0 length in
+    Lwt.return buffer
+
+(* encode/decode commit data *)
+let do_call client request =
+    let enc = Pbrt.Encoder.create () in
+    let () = encode_pb_commit request enc in
+    let msg = Pbrt.Encoder.to_bytes enc in
+    let%lwt () = call_write client.oc msg in
+    let%lwt resp = call_read client.ic in
+    decode_pb_commit (Pbrt.Decoder.of_bytes resp) |> Lwt.return
+
+(* socket management and commit callback *)
+let create sockfile =
+    let open Lwt_unix in
+    let sock = socket PF_UNIX SOCK_STREAM 0 in
+    let%lwt () = connect sock (ADDR_UNIX sockfile) in
+    let ic = Lwt_io.of_fd ~mode:Lwt_io.Input sock in
+    let oc = Lwt_io.of_fd ~mode:Lwt_io.Output sock in
+    Lwt.return { ic=ic; oc=oc; }
+
+let update session_data =
+    Lwt.return (commit_store session_data)
+
+let do_commit session_data =
+    let session = commit_data_to_commit_proto session_data in
+    let run () =
+        let sockfile = "/run/vyos-commitd.sock" in
+        let%lwt client = create sockfile in
+        let%lwt resp = do_call client session in
+        let%lwt () = Lwt_io.close client.oc in
+        update (commit_proto_to_commit_data resp session_data)
+    in Lwt_main.run @@ run ()
+
+(* test function *)
+let test_commit at wt =
+    let vc =
+        ST.load_daemon_config DF.defaults.config_file in
+    let () =
+        IC.write_internal at (FP.concat vc.session_dir vc.running_cache) in
+    let () =
+        IC.write_internal wt (FP.concat vc.session_dir vc.session_cache) in
+    let rt_opt =
+        ST.read_reference_tree (FP.concat vc.reftree_dir vc.reference_tree)
+    in
+    match rt_opt with
+    | Error msg -> print_endline msg
+    | Ok rt ->
+        let del_list, add_list =
+            calculate_priority_lists rt at wt
+        in
+        let commit_session =
+            { default_commit_data with node_list = del_list @ add_list }
+        in
+        do_commit commit_session
diff --git a/src/vycall_client.mli b/src/vycall_client.mli
new file mode 100644
index 0000000..8836f73
--- /dev/null
+++ b/src/vycall_client.mli
@@ -0,0 +1 @@
+val test_commit : Vyos1x.Config_tree.t -> Vyos1x.Config_tree.t -> unit
diff --git a/src/vycall_pbt.ml b/src/vycall_pbt.ml
new file mode 100644
index 0000000..8cccb0a
--- /dev/null
+++ b/src/vycall_pbt.ml
@@ -0,0 +1,349 @@
+[@@@ocaml.warning "-27-30-39-44"]
+
+type status = {
+  success : bool;
+  out : string;
+}
+
+type call = {
+  script_name : string;
+  tag_value : string option;
+  arg_value : string option;
+  reply : status option;
+}
+
+type commit = {
+  session_id : string;
+  named_active : string option;
+  named_proposed : string option;
+  dry_run : bool;
+  atomic : bool;
+  background : bool;
+  init : status option;
+  calls : call list;
+}
+
+let rec default_status 
+  ?success:((success:bool) = false)
+  ?out:((out:string) = "")
+  () : status  = {
+  success;
+  out;
+}
+
+let rec default_call 
+  ?script_name:((script_name:string) = "")
+  ?tag_value:((tag_value:string option) = None)
+  ?arg_value:((arg_value:string option) = None)
+  ?reply:((reply:status option) = None)
+  () : call  = {
+  script_name;
+  tag_value;
+  arg_value;
+  reply;
+}
+
+let rec default_commit 
+  ?session_id:((session_id:string) = "")
+  ?named_active:((named_active:string option) = None)
+  ?named_proposed:((named_proposed:string option) = None)
+  ?dry_run:((dry_run:bool) = false)
+  ?atomic:((atomic:bool) = false)
+  ?background:((background:bool) = false)
+  ?init:((init:status option) = None)
+  ?calls:((calls:call list) = [])
+  () : commit  = {
+  session_id;
+  named_active;
+  named_proposed;
+  dry_run;
+  atomic;
+  background;
+  init;
+  calls;
+}
+
+type status_mutable = {
+  mutable success : bool;
+  mutable out : string;
+}
+
+let default_status_mutable () : status_mutable = {
+  success = false;
+  out = "";
+}
+
+type call_mutable = {
+  mutable script_name : string;
+  mutable tag_value : string option;
+  mutable arg_value : string option;
+  mutable reply : status option;
+}
+
+let default_call_mutable () : call_mutable = {
+  script_name = "";
+  tag_value = None;
+  arg_value = None;
+  reply = None;
+}
+
+type commit_mutable = {
+  mutable session_id : string;
+  mutable named_active : string option;
+  mutable named_proposed : string option;
+  mutable dry_run : bool;
+  mutable atomic : bool;
+  mutable background : bool;
+  mutable init : status option;
+  mutable calls : call list;
+}
+
+let default_commit_mutable () : commit_mutable = {
+  session_id = "";
+  named_active = None;
+  named_proposed = None;
+  dry_run = false;
+  atomic = false;
+  background = false;
+  init = None;
+  calls = [];
+}
+
+[@@@ocaml.warning "-27-30-39"]
+
+(** {2 Formatters} *)
+
+let rec pp_status fmt (v:status) = 
+  let pp_i fmt () =
+    Pbrt.Pp.pp_record_field ~first:true "success" Pbrt.Pp.pp_bool fmt v.success;
+    Pbrt.Pp.pp_record_field ~first:false "out" Pbrt.Pp.pp_string fmt v.out;
+  in
+  Pbrt.Pp.pp_brk pp_i fmt ()
+
+let rec pp_call fmt (v:call) = 
+  let pp_i fmt () =
+    Pbrt.Pp.pp_record_field ~first:true "script_name" Pbrt.Pp.pp_string fmt v.script_name;
+    Pbrt.Pp.pp_record_field ~first:false "tag_value" (Pbrt.Pp.pp_option Pbrt.Pp.pp_string) fmt v.tag_value;
+    Pbrt.Pp.pp_record_field ~first:false "arg_value" (Pbrt.Pp.pp_option Pbrt.Pp.pp_string) fmt v.arg_value;
+    Pbrt.Pp.pp_record_field ~first:false "reply" (Pbrt.Pp.pp_option pp_status) fmt v.reply;
+  in
+  Pbrt.Pp.pp_brk pp_i fmt ()
+
+let rec pp_commit fmt (v:commit) = 
+  let pp_i fmt () =
+    Pbrt.Pp.pp_record_field ~first:true "session_id" Pbrt.Pp.pp_string fmt v.session_id;
+    Pbrt.Pp.pp_record_field ~first:false "named_active" (Pbrt.Pp.pp_option Pbrt.Pp.pp_string) fmt v.named_active;
+    Pbrt.Pp.pp_record_field ~first:false "named_proposed" (Pbrt.Pp.pp_option Pbrt.Pp.pp_string) fmt v.named_proposed;
+    Pbrt.Pp.pp_record_field ~first:false "dry_run" Pbrt.Pp.pp_bool fmt v.dry_run;
+    Pbrt.Pp.pp_record_field ~first:false "atomic" Pbrt.Pp.pp_bool fmt v.atomic;
+    Pbrt.Pp.pp_record_field ~first:false "background" Pbrt.Pp.pp_bool fmt v.background;
+    Pbrt.Pp.pp_record_field ~first:false "init" (Pbrt.Pp.pp_option pp_status) fmt v.init;
+    Pbrt.Pp.pp_record_field ~first:false "calls" (Pbrt.Pp.pp_list pp_call) fmt v.calls;
+  in
+  Pbrt.Pp.pp_brk pp_i fmt ()
+
+[@@@ocaml.warning "-27-30-39"]
+
+(** {2 Protobuf Encoding} *)
+
+let rec encode_pb_status (v:status) encoder = 
+  Pbrt.Encoder.bool v.success encoder;
+  Pbrt.Encoder.key 1 Pbrt.Varint encoder; 
+  Pbrt.Encoder.string v.out encoder;
+  Pbrt.Encoder.key 2 Pbrt.Bytes encoder; 
+  ()
+
+let rec encode_pb_call (v:call) encoder = 
+  Pbrt.Encoder.string v.script_name encoder;
+  Pbrt.Encoder.key 1 Pbrt.Bytes encoder; 
+  begin match v.tag_value with
+  | Some x -> 
+    Pbrt.Encoder.string x encoder;
+    Pbrt.Encoder.key 2 Pbrt.Bytes encoder; 
+  | None -> ();
+  end;
+  begin match v.arg_value with
+  | Some x -> 
+    Pbrt.Encoder.string x encoder;
+    Pbrt.Encoder.key 3 Pbrt.Bytes encoder; 
+  | None -> ();
+  end;
+  begin match v.reply with
+  | Some x -> 
+    Pbrt.Encoder.nested encode_pb_status x encoder;
+    Pbrt.Encoder.key 4 Pbrt.Bytes encoder; 
+  | None -> ();
+  end;
+  ()
+
+let rec encode_pb_commit (v:commit) encoder = 
+  Pbrt.Encoder.string v.session_id encoder;
+  Pbrt.Encoder.key 1 Pbrt.Bytes encoder; 
+  begin match v.named_active with
+  | Some x -> 
+    Pbrt.Encoder.string x encoder;
+    Pbrt.Encoder.key 2 Pbrt.Bytes encoder; 
+  | None -> ();
+  end;
+  begin match v.named_proposed with
+  | Some x -> 
+    Pbrt.Encoder.string x encoder;
+    Pbrt.Encoder.key 3 Pbrt.Bytes encoder; 
+  | None -> ();
+  end;
+  Pbrt.Encoder.bool v.dry_run encoder;
+  Pbrt.Encoder.key 4 Pbrt.Varint encoder; 
+  Pbrt.Encoder.bool v.atomic encoder;
+  Pbrt.Encoder.key 5 Pbrt.Varint encoder; 
+  Pbrt.Encoder.bool v.background encoder;
+  Pbrt.Encoder.key 6 Pbrt.Varint encoder; 
+  begin match v.init with
+  | Some x -> 
+    Pbrt.Encoder.nested encode_pb_status x encoder;
+    Pbrt.Encoder.key 7 Pbrt.Bytes encoder; 
+  | None -> ();
+  end;
+  Pbrt.List_util.rev_iter_with (fun x encoder -> 
+    Pbrt.Encoder.nested encode_pb_call x encoder;
+    Pbrt.Encoder.key 8 Pbrt.Bytes encoder; 
+  ) v.calls encoder;
+  ()
+
+[@@@ocaml.warning "-27-30-39"]
+
+(** {2 Protobuf Decoding} *)
+
+let rec decode_pb_status d =
+  let v = default_status_mutable () in
+  let continue__= ref true in
+  let out_is_set = ref false in
+  let success_is_set = ref false in
+  while !continue__ do
+    match Pbrt.Decoder.key d with
+    | None -> (
+    ); continue__ := false
+    | Some (1, Pbrt.Varint) -> begin
+      v.success <- Pbrt.Decoder.bool d; success_is_set := true;
+    end
+    | Some (1, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(status), field(1)" pk
+    | Some (2, Pbrt.Bytes) -> begin
+      v.out <- Pbrt.Decoder.string d; out_is_set := true;
+    end
+    | Some (2, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(status), field(2)" pk
+    | Some (_, payload_kind) -> Pbrt.Decoder.skip d payload_kind
+  done;
+  begin if not !out_is_set then Pbrt.Decoder.missing_field "out" end;
+  begin if not !success_is_set then Pbrt.Decoder.missing_field "success" end;
+  ({
+    success = v.success;
+    out = v.out;
+  } : status)
+
+let rec decode_pb_call d =
+  let v = default_call_mutable () in
+  let continue__= ref true in
+  let script_name_is_set = ref false in
+  while !continue__ do
+    match Pbrt.Decoder.key d with
+    | None -> (
+    ); continue__ := false
+    | Some (1, Pbrt.Bytes) -> begin
+      v.script_name <- Pbrt.Decoder.string d; script_name_is_set := true;
+    end
+    | Some (1, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(call), field(1)" pk
+    | Some (2, Pbrt.Bytes) -> begin
+      v.tag_value <- Some (Pbrt.Decoder.string d);
+    end
+    | Some (2, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(call), field(2)" pk
+    | Some (3, Pbrt.Bytes) -> begin
+      v.arg_value <- Some (Pbrt.Decoder.string d);
+    end
+    | Some (3, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(call), field(3)" pk
+    | Some (4, Pbrt.Bytes) -> begin
+      v.reply <- Some (decode_pb_status (Pbrt.Decoder.nested d));
+    end
+    | Some (4, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(call), field(4)" pk
+    | Some (_, payload_kind) -> Pbrt.Decoder.skip d payload_kind
+  done;
+  begin if not !script_name_is_set then Pbrt.Decoder.missing_field "script_name" end;
+  ({
+    script_name = v.script_name;
+    tag_value = v.tag_value;
+    arg_value = v.arg_value;
+    reply = v.reply;
+  } : call)
+
+let rec decode_pb_commit d =
+  let v = default_commit_mutable () in
+  let continue__= ref true in
+  let background_is_set = ref false in
+  let atomic_is_set = ref false in
+  let dry_run_is_set = ref false in
+  let session_id_is_set = ref false in
+  while !continue__ do
+    match Pbrt.Decoder.key d with
+    | None -> (
+      v.calls <- List.rev v.calls;
+    ); continue__ := false
+    | Some (1, Pbrt.Bytes) -> begin
+      v.session_id <- Pbrt.Decoder.string d; session_id_is_set := true;
+    end
+    | Some (1, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(commit), field(1)" pk
+    | Some (2, Pbrt.Bytes) -> begin
+      v.named_active <- Some (Pbrt.Decoder.string d);
+    end
+    | Some (2, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(commit), field(2)" pk
+    | Some (3, Pbrt.Bytes) -> begin
+      v.named_proposed <- Some (Pbrt.Decoder.string d);
+    end
+    | Some (3, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(commit), field(3)" pk
+    | Some (4, Pbrt.Varint) -> begin
+      v.dry_run <- Pbrt.Decoder.bool d; dry_run_is_set := true;
+    end
+    | Some (4, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(commit), field(4)" pk
+    | Some (5, Pbrt.Varint) -> begin
+      v.atomic <- Pbrt.Decoder.bool d; atomic_is_set := true;
+    end
+    | Some (5, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(commit), field(5)" pk
+    | Some (6, Pbrt.Varint) -> begin
+      v.background <- Pbrt.Decoder.bool d; background_is_set := true;
+    end
+    | Some (6, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(commit), field(6)" pk
+    | Some (7, Pbrt.Bytes) -> begin
+      v.init <- Some (decode_pb_status (Pbrt.Decoder.nested d));
+    end
+    | Some (7, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(commit), field(7)" pk
+    | Some (8, Pbrt.Bytes) -> begin
+      v.calls <- (decode_pb_call (Pbrt.Decoder.nested d)) :: v.calls;
+    end
+    | Some (8, pk) -> 
+      Pbrt.Decoder.unexpected_payload "Message(commit), field(8)" pk
+    | Some (_, payload_kind) -> Pbrt.Decoder.skip d payload_kind
+  done;
+  begin if not !background_is_set then Pbrt.Decoder.missing_field "background" end;
+  begin if not !atomic_is_set then Pbrt.Decoder.missing_field "atomic" end;
+  begin if not !dry_run_is_set then Pbrt.Decoder.missing_field "dry_run" end;
+  begin if not !session_id_is_set then Pbrt.Decoder.missing_field "session_id" end;
+  ({
+    session_id = v.session_id;
+    named_active = v.named_active;
+    named_proposed = v.named_proposed;
+    dry_run = v.dry_run;
+    atomic = v.atomic;
+    background = v.background;
+    init = v.init;
+    calls = v.calls;
+  } : commit)
diff --git a/src/vycall_pbt.mli b/src/vycall_pbt.mli
new file mode 100644
index 0000000..5c8bd20
--- /dev/null
+++ b/src/vycall_pbt.mli
@@ -0,0 +1,99 @@
+
+(** Code for vycall.proto *)
+
+(* generated from "data/vycall.proto", do not edit *)
+
+
+
+(** {2 Types} *)
+
+type status = {
+  success : bool;
+  out : string;
+}
+
+type call = {
+  script_name : string;
+  tag_value : string option;
+  arg_value : string option;
+  reply : status option;
+}
+
+type commit = {
+  session_id : string;
+  named_active : string option;
+  named_proposed : string option;
+  dry_run : bool;
+  atomic : bool;
+  background : bool;
+  init : status option;
+  calls : call list;
+}
+
+
+(** {2 Basic values} *)
+
+val default_status : 
+  ?success:bool ->
+  ?out:string ->
+  unit ->
+  status
+(** [default_status ()] is the default value for type [status] *)
+
+val default_call : 
+  ?script_name:string ->
+  ?tag_value:string option ->
+  ?arg_value:string option ->
+  ?reply:status option ->
+  unit ->
+  call
+(** [default_call ()] is the default value for type [call] *)
+
+val default_commit : 
+  ?session_id:string ->
+  ?named_active:string option ->
+  ?named_proposed:string option ->
+  ?dry_run:bool ->
+  ?atomic:bool ->
+  ?background:bool ->
+  ?init:status option ->
+  ?calls:call list ->
+  unit ->
+  commit
+(** [default_commit ()] is the default value for type [commit] *)
+
+
+(** {2 Formatters} *)
+
+val pp_status : Format.formatter -> status -> unit 
+(** [pp_status v] formats v *)
+
+val pp_call : Format.formatter -> call -> unit 
+(** [pp_call v] formats v *)
+
+val pp_commit : Format.formatter -> commit -> unit 
+(** [pp_commit v] formats v *)
+
+
+(** {2 Protobuf Encoding} *)
+
+val encode_pb_status : status -> Pbrt.Encoder.t -> unit
+(** [encode_pb_status v encoder] encodes [v] with the given [encoder] *)
+
+val encode_pb_call : call -> Pbrt.Encoder.t -> unit
+(** [encode_pb_call v encoder] encodes [v] with the given [encoder] *)
+
+val encode_pb_commit : commit -> Pbrt.Encoder.t -> unit
+(** [encode_pb_commit v encoder] encodes [v] with the given [encoder] *)
+
+
+(** {2 Protobuf Decoding} *)
+
+val decode_pb_status : Pbrt.Decoder.t -> status
+(** [decode_pb_status decoder] decodes a [status] binary value from [decoder] *)
+
+val decode_pb_call : Pbrt.Decoder.t -> call
+(** [decode_pb_call decoder] decodes a [call] binary value from [decoder] *)
+
+val decode_pb_commit : Pbrt.Decoder.t -> commit
+(** [decode_pb_commit decoder] decodes a [commit] binary value from [decoder] *)
diff --git a/src/vyconf_config.ml b/src/vyconf_config.ml
index bef607f..5fbd716 100644
--- a/src/vyconf_config.ml
+++ b/src/vyconf_config.ml
@@ -6,9 +6,12 @@ type t = {
     program_dir: string;
     config_dir: string;
     reftree_dir: string;
+    session_dir: string;
     primary_config: string;
     fallback_config: string;
     reference_tree: string;
+    running_cache: string;
+    session_cache: string;
     socket: string;
     pid_file: string;
     log_file: string option;
@@ -24,9 +27,12 @@ let empty_config = {
     program_dir = "";
     config_dir = "";
     reftree_dir = "";
+    session_dir = "";
     primary_config = "";
     fallback_config = "";
     reference_tree = "";
+    running_cache = "";
+    session_cache = "";
     socket = "";
     pid_file = "";
     log_file = None;
@@ -63,10 +69,13 @@ let load filename =
             let conf = {conf with data_dir = mandatory_field conf_toml "appliance" "data_dir"} in
             let conf = {conf with config_dir = mandatory_field conf_toml "appliance" "config_dir"} in
             let conf = {conf with reftree_dir = mandatory_field conf_toml "appliance" "reftree_dir"} in
+            let conf = {conf with session_dir = mandatory_field conf_toml "appliance" "session_dir"} in
             let conf = {conf with program_dir = mandatory_field conf_toml "appliance" "program_dir"} in
             let conf = {conf with primary_config = mandatory_field conf_toml "appliance" "primary_config"} in
             let conf = {conf with fallback_config = mandatory_field conf_toml "appliance" "fallback_config"} in
             let conf = {conf with reference_tree = mandatory_field conf_toml "appliance" "reference_tree"} in
+            let conf = {conf with running_cache = mandatory_field conf_toml "appliance" "running_cache"} in
+            let conf = {conf with session_cache = mandatory_field conf_toml "appliance" "session_cache"} in
             (* Optional fields *)
             let conf = {conf with pid_file = optional_field defaults.pid_file conf_toml "vyconf" "pid_file"} in
             let conf = {conf with socket = optional_field defaults.socket conf_toml "vyconf" "socket"} in
diff --git a/src/vyconf_config.mli b/src/vyconf_config.mli
index dad574c..9b6b283 100644
--- a/src/vyconf_config.mli
+++ b/src/vyconf_config.mli
@@ -4,9 +4,12 @@ type t = {
     program_dir: string;
     config_dir: string;
     reftree_dir: string;
+    session_dir: string;
     primary_config: string;
     fallback_config: string;
     reference_tree: string;
+    running_cache: string;
+    session_cache: string;
     socket: string;
     pid_file: string;
     log_file: string option;