Node: adds version to data directory

src/node/main/node_config_file.ml

@@ -257,7 +257,7 @@ let read fp =
     return default_config
 
 let write fp cfg =
-  Lwt_utils.create_dir ~perm:0o700 (Filename.dirname fp) >>= fun () ->
+  Node_data_version.ensure_data_dir (Filename.dirname fp) >>=? fun () ->
   Data_encoding_ezjsonm.write_file fp
     (Data_encoding.Json.construct encoding cfg)
 
@@ -284,6 +284,8 @@ let update
     ?rpc_tls
     ?log_output
     cfg =
+  let data_dir = Utils.unopt ~default:cfg.data_dir data_dir in
+  Node_data_version.ensure_data_dir data_dir >>=? fun () ->
   let peer_table_size =
     map_option peer_table_size ~f:(fun i -> i, i / 4 * 3) in
   let unopt_list ~default = function
@@ -343,8 +345,7 @@ let update
     output = Utils.unopt ~default:cfg.log.output log_output ;
   }
   in
-  { data_dir = Utils.unopt ~default:cfg.data_dir data_dir ;
-    net ; rpc ; log }
+  return { data_dir ; net ; rpc ; log }
 
 let resolve_addr ?default_port ?(passive = false) peer =
   let addr, port = Utils.parse_addr_port peer in

src/node/main/node_config_file.mli

@@ -67,7 +67,7 @@ val update:
   ?cors_headers:string list ->
   ?rpc_tls:tls ->
   ?log_output:Logging.Output.t ->
-  t -> t
+  t -> t tzresult Lwt.t
 
 val to_string: t -> string
 val read: string -> t tzresult Lwt.t

src/node/main/node_data_version.ml

@@ -0,0 +1,94 @@
+(**************************************************************************)
+(*                                                                        *)
+(*    Copyright (c) 2014 - 2016.                                          *)
+(*    Dynamic Ledger Solutions, Inc. <contact@tezos.com>                  *)
+(*                                                                        *)
+(*    All rights reserved. No warranty, explicit or implicit, provided.   *)
+(*                                                                        *)
+(**************************************************************************)
+
+open Error_monad
+
+type t = string
+
+let data_version = "0.0.1"
+
+let version_encoding = Data_encoding.(obj1 (req "version" string))
+
+let version_file_name = "version.json"
+
+let pp ppf version = Format.pp_print_string ppf version
+
+type error += Invalid_data_dir_version of t * t
+type error += No_data_dir_version_file of string
+type error += Could_not_read_data_dir_version of string
+
+let () =
+  register_error_kind
+    `Permanent
+    ~id: "invalidDataDirVersion"
+    ~title: "Invalid data directory version"
+    ~description: "The data directory version was not the one that was expected"
+    Data_encoding.(obj2
+                    (req "expectedVersion" string)
+                    (req "actualVersion" string))
+    (function
+      | Invalid_data_dir_version (expected, actual) ->
+          Some (expected, actual)
+      | _ -> None)
+    (fun (expected, actual) -> Invalid_data_dir_version (expected, actual)) ;
+  register_error_kind
+    `Permanent
+    ~id: "couldNotReadDataDirVersion"
+    ~title: "Could not read data directory version file"
+    ~description: "Data directory version file was invalid."
+    Data_encoding.(obj1 (req "versionPath" string))
+    ~pp:(fun ppf path ->
+        Format.fprintf ppf
+          "Tried to read version file at '%s', \
+          \ but the file could not be parsed."
+          path)
+    (function Could_not_read_data_dir_version path -> Some path | _ -> None)
+    (fun path -> Could_not_read_data_dir_version path);
+  register_error_kind
+    `Permanent
+    ~id: "noDataDirVersionFile"
+    ~title: "Data directory version file did not exist"
+    ~description: "Data directory version file did not exist"
+    Data_encoding.(obj1 (req "versionPath" string))
+    ~pp:(fun ppf path ->
+        Format.fprintf ppf
+          "Expected to find data directory version file at '%s', \
+           \ but the file did not exist."
+          path)
+    (function No_data_dir_version_file path -> Some path | _ -> None)
+    (fun path -> No_data_dir_version_file path)
+
+let version_file data_dir =
+  (Filename.concat data_dir version_file_name)
+
+let check_data_dir_version data_dir =
+  let version_file = version_file data_dir in
+  fail_unless (Sys.file_exists version_file)
+    (No_data_dir_version_file version_file) >>=? fun () ->
+  Data_encoding_ezjsonm.read_file version_file
+  |> trace (Could_not_read_data_dir_version version_file) >>=? fun json ->
+  begin
+    try return (Data_encoding.Json.destruct version_encoding json)
+    with _ -> fail (Could_not_read_data_dir_version version_file)
+  end >>=? fun version ->
+  fail_unless
+    (String.equal data_version version)
+    (Invalid_data_dir_version (data_version, version)) >>=? fun () ->
+  return ()
+
+let ensure_data_dir data_dir =
+  if Sys.file_exists data_dir &&
+     (Array.length (Sys.readdir data_dir)) > 0
+  then
+    check_data_dir_version data_dir
+  else
+    Lwt_utils.create_dir ~perm:0o700 data_dir >>= fun () ->
+    Data_encoding_ezjsonm.write_file
+      (version_file data_dir)
+      (Data_encoding.Json.construct version_encoding data_version)

src/node/main/node_data_version.mli

@@ -0,0 +1,21 @@
+(**************************************************************************)
+(*                                                                        *)
+(*    Copyright (c) 2014 - 2016.                                          *)
+(*    Dynamic Ledger Solutions, Inc. <contact@tezos.com>                  *)
+(*                                                                        *)
+(*    All rights reserved. No warranty, explicit or implicit, provided.   *)
+(*                                                                        *)
+(**************************************************************************)
+
+type t
+
+type error += Invalid_data_dir_version of t * t
+type error += Could_not_read_data_dir_version of string
+
+val data_version : t
+
+val pp : Format.formatter -> t -> unit
+
+val version_encoding : t Data_encoding.encoding
+
+val ensure_data_dir : string -> unit tzresult Lwt.t

src/node/main/node_identity_command.ml

@@ -67,7 +67,7 @@ module Term = struct
             Node_config_file.read config_file >>=? fun cfg ->
             return { cfg with data_dir }
       end >>=? fun cfg ->
-      let cfg = Node_config_file.update ?expected_pow cfg in
+      Node_config_file.update ?expected_pow cfg >>=? fun cfg ->
       match subcommand with
       | Show -> show cfg
       | Generate -> generate cfg

src/node/main/node_identity_file.ml

@@ -81,6 +81,6 @@ let write file identity =
   if Sys.file_exists file then
     fail (Existent_identity_file file)
   else
-    Lwt_utils.create_dir ~perm:0o700 (Filename.dirname file) >>= fun () ->
+    Node_data_version.ensure_data_dir (Filename.dirname file) >>=? fun () ->
     Data_encoding_ezjsonm.write_file file
       (Data_encoding.Json.construct P2p.Identity.encoding identity)

src/node/main/node_run_command.ml

@@ -185,7 +185,7 @@ let init_signal () =
   ignore (Lwt_unix.on_signal Sys.sigterm handler : Lwt_unix.signal_handler_id)
 
 let run ?verbosity ?sandbox (config : Node_config_file.t) =
-  Lwt_utils.create_dir config.data_dir >>= fun () ->
+  Node_data_version.ensure_data_dir config.data_dir >>=? fun () ->
   Lwt_utils.Lock_file.create
     ~unlink_on_exit:true (lock_file config.data_dir) >>=? fun () ->
   init_signal () ;

src/node/main/node_shared_arg.ml

@@ -267,7 +267,6 @@ let read_and_patch_config_file ?(ignore_bootstrap_peers=false) args =
       peers
     end else
       cfg.net.bootstrap_peers @ peers in
-  return @@
   Node_config_file.update
     ?data_dir ?min_connections ?expected_connections ?max_connections
     ?max_download_speed ?max_upload_speed ?binary_chunks_size