Client: add command "complete".

src/Makefile

@@ -345,6 +345,7 @@ CLIENT_LIB_INTFS := \
   client/client_version.mli \
   client/client_node_rpcs.mli \
   client/client_generic_rpcs.mli \
+  client/client_helpers.mli \
   client/client_aliases.mli \
   client/client_keys.mli \
   client/client_protocols.mli \
@@ -354,6 +355,7 @@ CLIENT_LIB_IMPLS := \
   client/client_config.ml \
   client/client_node_rpcs.ml \
   client/client_generic_rpcs.ml \
+  client/client_helpers.ml \
   client/client_aliases.ml \
   client/client_keys.ml \
   client/client_protocols.ml \

src/client/client_helpers.ml

@@ -0,0 +1,35 @@
+(**************************************************************************)
+(*                                                                        *)
+(*    Copyright (c) 2014 - 2016.                                          *)
+(*    Dynamic Ledger Solutions, Inc. <contact@tezos.com>                  *)
+(*                                                                        *)
+(*    All rights reserved. No warranty, explicit or implicit, provided.   *)
+(*                                                                        *)
+(**************************************************************************)
+
+let () =
+  let open Cli_entries in
+  register_group "helpers" "Various helpers"
+
+let unique = ref false
+let unique_arg =
+  "-unique",
+  Arg.Set unique,
+  "Fail when there is more than one possible completion."
+
+let commands () = Cli_entries.[
+    command
+      ~desc: "Lookup for the possible completion of a \
+              given prefix of Base48Check-encoded hash. This actually \
+              works only for blocks and operations."
+      ~args: [unique_arg]
+      (prefixes [ "complete" ] @@ string "prefix" "the prefix of the Base48Check-encoded hash to be completed" @@ stop)
+      (fun prefix () ->
+         Client_node_rpcs.complete prefix >>= fun completions ->
+         match completions with
+         | [] -> Pervasives.exit 3
+         | _ :: _ :: _ when !unique -> Pervasives.exit 3
+         | completions ->
+             List.iter print_endline completions ;
+             Lwt.return_unit)
+]

src/client/client_helpers.mli

@@ -0,0 +1,10 @@
+(**************************************************************************)
+(*                                                                        *)
+(*    Copyright (c) 2014 - 2016.                                          *)
+(*    Dynamic Ledger Solutions, Inc. <contact@tezos.com>                  *)
+(*                                                                        *)
+(*    All rights reserved. No warranty, explicit or implicit, provided.   *)
+(*                                                                        *)
+(**************************************************************************)
+
+val commands: unit -> Cli_entries.command list

src/client/client_node_rpcs.ml

@@ -150,6 +150,8 @@ let inject_operation ?(wait = true) ?force operation =
   call_service0 Services.inject_operation (operation, wait, force)
 let inject_protocol ?(wait = true) ?force protocol =
   call_service0 Services.inject_protocol (protocol, wait, force)
+let complete prefix =
+  call_service1 Services.complete prefix ()
 let describe ?recurse path =
   let prefix, arg = RPC.forge_request Services.describe () recurse in
   get_json (prefix @ path) arg >>=

src/client/client_node_rpcs.mli

@@ -104,6 +104,8 @@ module Protocols : sig
     (Protocol_hash.t * Store.protocol option) list Lwt.t
 end
 
+val complete: string -> string list Lwt.t
+
 val describe: ?recurse:bool -> string list -> RPC.Description.directory_descr Lwt.t
 
 (** Low-level *)

src/client_main.ml

@@ -31,6 +31,7 @@ let main () =
          Client_generic_rpcs.commands @
          Client_keys.commands () @
          Client_protocols.commands () @
+         Client_helpers.commands () @
          Client_version.commands_for_version version in
        Client_config.parse_args ~version
          (Cli_entries.usage commands)

src/node/shell/node_rpc.ml

@@ -434,6 +434,11 @@ let build_rpc_directory node =
     let implementation () =
       RPC.Answer.return Data_encoding.Json.(schema (Error_monad.error_encoding ())) in
     RPC.register0 dir RPC.Error.service implementation in
+  let dir =
+    RPC.register1 dir Services.complete
+      (fun s () ->
+         Base48.decode_partial s >>= fun l ->
+        RPC.Answer.return (List.map Base48.encode l)) in
   let dir =
     RPC.register_describe_directory_service dir Services.describe in
   dir

src/node/shell/node_rpc_services.ml

@@ -583,6 +583,19 @@ let inject_protocol =
        (obj1 (req "injectedProtocol" Protocol_hash.encoding)))
     RPC.Path.(root / "inject_protocol")
 
+let complete =
+  let prefix_arg =
+    let destruct s = Ok s
+    and construct s = s in
+    RPC.Arg.make ~name:"prefix" ~destruct ~construct () in
+  RPC.service
+    ~description: "Try to complete a prefix of a Base48Check-encoded data. \
+                   This RPC is actually able to complete hashes of \
+                   black and hashes of operations."
+    ~input: empty
+    ~output: (list string)
+    RPC.Path.(root / "complete" /: prefix_arg )
+
 let describe =
   RPC.Description.service
     ~description: "RPCs documentation and input/output schema"

src/node/shell/node_rpc_services.mli

@@ -132,5 +132,7 @@ val inject_protocol:
   (unit, unit,
    (Store.protocol * bool * bool option), Protocol_hash.t tzresult) RPC.service
 
+val complete: (unit, unit * string, unit, string list) RPC.service
+
 val describe:
   (unit, unit, bool option, RPC.Description.directory_descr) RPC.service