Fix/backup restore (#7)

* Fix - deps

* (fix) Handle backup and restore correctly

rebar.lock

@@ -1,5 +1,9 @@
 {"1.1.0",
-[{<<"sext">>,{pkg,<<"sext">>,<<"1.6.0">>},0}]}.
+[{<<"erlfdb">>,
+  {git,"https://github.com/leonardb/couchdb-erlfdb.git",
+       {ref,"6a84378bd8637b58150c95b1905fd7257618f8dd"}},
+  0},
+ {<<"sext">>,{pkg,<<"sext">>,<<"1.6.0">>},0}]}.
 [
 {pkg_hash,[
  {<<"sext">>, <<"E5466AC5A9622AB1A6BCA4311913515082BB0F6A6799C73400906C0CD141AD5D">>}]}

src/mnesia_fdb.erl

@@ -151,6 +151,7 @@ register() ->
     register(default_alias()).
 
 register(Alias) ->
+    ?dbg("~p : register(~p)", [self(), Alias]),
     Module = ?MODULE,
     case mnesia:add_backend_type(Alias, Module) of
         {atomic, ok} ->
@@ -175,8 +176,8 @@ show_table(Tab) ->
 show_table(Alias, Tab) ->
     show_table(Alias, Tab, 100).
 
-show_table(_Alias, Tab, Limit) ->
-    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab),
+show_table(_Alias, Tab0, Limit) ->
+    #st{db = Db, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab0),
     DPfx = ?DATA_PREFIX(Type),
     StartKey = sext:prefix({TableId, DPfx, ?FDB_WC}),
     i_show_table(Db, TableId, StartKey, Limit).
@@ -295,6 +296,8 @@ check_definition_entry(_Tab, _Id, {type, T} = P) when T==set; T==ordered_set; T=
          [self(), _Tab, _Id, {type, T}, pp_stack()]),
     P;
 check_definition_entry(Tab, Id, {type, T}) ->
+    ?dbg("~p: check_definition_entry(~p, ~p, ~p);~n Trace: ~s~n",
+         [self(), Tab, Id, {type, T}, pp_stack()]),
     mnesia:abort({combine_error, Tab, [Id, {type, T}]});
 check_definition_entry(_Tab, _Id, {user_properties, UPs} = P) ->
     FdbOpts = proplists:get_value(fdb_opts, UPs, []),
@@ -317,9 +320,13 @@ check_definition_entry(_Tab, _Id, P) ->
     P.
 
 create_table(_Alias, Tab, Props) ->
+    ?dbg("~p :: create_table(~p, ~p, ~p)", [self(), _Alias, Tab, Props]),
     mnesia_fdb_manager:create(Tab, Props).
 
+load_table(_Alias, Tab, restore, Props) ->
+    mnesia_fdb_manager:create(Tab, Props);
 load_table(_Alias, Tab, _LoadReason, _Opts) ->
+    ?dbg("~p :: load_table(~p, ~p, ~p, ~p)", [self(), _Alias, Tab, _LoadReason, _Opts]),
     case mnesia_fdb_manager:st(Tab) of
         #st{} ->
             %% Table is loaded
@@ -329,6 +336,7 @@ load_table(_Alias, Tab, _LoadReason, _Opts) ->
     end.
 
 close_table(_Alias, _Tab) ->
+    ?dbg("~p: close_table(~p, ~p)~n", [self(), _Alias, _Tab]),
     ok.
 
 -ifndef(MNESIA_FDB_NO_DBG).
@@ -366,16 +374,25 @@ sync_close_table(Alias, Tab) ->
 delete_table(Alias, Tab) ->
     ?dbg("~p: delete_table(~p, ~p);~n Trace: ~s~n",
          [self(), Alias, Tab, pp_stack()]),
-    ok = mnesia_fdb_manager:delete(Tab).
+    case mnesia_fdb_manager:load_if_exists(Tab) of
+        ok ->
+            mnesia_fdb_manager:delete(Tab);
+        {error, not_found} ->
+            ok
+    end.
 
 info(_Alias, _Tab, memory) ->
+    ?dbg("~p: info(~p, ~p, ~p)~n", [self(), _Alias, _Tab, memory]),
     0;
 info(_Alias, _Tab, size) ->
+    ?dbg("~p: info(~p, ~p, ~p)~n", [self(), _Alias, _Tab, size]),
     0;
 info(_Alias, _Tab, _Item) ->
+    ?dbg("~p: info(~p, ~p, ~p)~n", [self(), _Alias, _Tab, _Item]),
     undefined.
 
 write_info(_Alias, _Tab, _Key, _Value) ->
+    ?dbg("~p: write_info(~p, ~p, ~p, ~p)~n", [self(), _Alias, _Tab, _Key, _Value]),
     ok.
 
 %% table sync calls
@@ -416,6 +433,7 @@ write_info(_Alias, _Tab, _Key, _Value) ->
 %%
 
 sender_init(Alias, Tab, _RemoteStorage, _Pid) ->
+    ?dbg("~p: sender_init(~p, ~p, ~p, ~p)~n", [self(), Alias, Tab, _RemoteStorage, _Pid]),
     %% Need to send a message to the receiver. It will be handled in
     %% receiver_first_message/4 below. There could be a volley of messages...
     {standard,
@@ -439,6 +457,7 @@ receive_data(Data, Alias, Tab, _Sender, State) ->
     {more, State}.
 
 receive_done(_Alias, _Tab, _Sender, _State) ->
+    ?dbg("~p : receiver_done(~p, ~p, ~p, ~p)", [self(), _Alias, _Tab, _Sender, _State]),
     ok.
 
 %% End of table synch protocol
@@ -460,13 +479,14 @@ delete(Alias, Tab, Key) ->
 
 %% Not relevant for an ordered_set
 fixtable(_Alias, _Tab, _Bool) ->
-    ?dbg("~p : fixtable(~p, ~p, ~p)", [self(),_Alias, _Tab, _Bool]),
+    ?dbg("~p : fixtable(~p, ~p, ~p)", [self(), _Alias, _Tab, _Bool]),
     ok.
 
 %% To save storage space, we avoid storing the key twice. The key
 %% in the record is replaced with []. It has to be put back in lookup/3.
-insert(_Alias, Tab, Obj) ->
-    #st{tab = Tab} = St = mnesia_fdb_manager:st(Tab),
+insert(_Alias, Tab0, Obj) ->
+    ?dbg("~p : insert(~p, ~p, ~p)", [self(),_Alias, Tab0, Obj]),
+    #st{tab = Tab} = St = mnesia_fdb_manager:st(Tab0),
     %% St = call(Alias, Tab, get_st),
     Pos = keypos(Tab),
     Key = element(Pos, Obj),
@@ -475,12 +495,12 @@ insert(_Alias, Tab, Obj) ->
 
 %% Since the key is replaced with [] in the record, we have to put it back
 %% into the found record.
-lookup(Alias, Tab, Key) ->
-    ?dbg("~p : lookup(~p, ~p, ~p)", [self(), Alias, Tab, Key]),
-    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab),
+lookup(Alias, Tab0, Key) ->
+    ?dbg("~p : lookup(~p, ~p, ~p)", [self(), Alias, Tab0, Key]),
+    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab0),
     case Type of
         bag ->
-            lookup_bag(Db, TableId, Key, keypos(Tab));
+            lookup_bag(Db, TableId, Key, keypos(Tab0));
         _ ->
             EncKey = sext:encode({TableId, ?DATA_PREFIX(Type), Key}),
             case erlfdb:get(Db, EncKey) of
@@ -506,12 +526,12 @@ lookup_bag(Db, TableId, Key, KeyPos) ->
              end || {EKey, EVal} <- Rows]
     end.
 
-match_delete(Alias, Tab, Pat) when is_atom(Pat) ->
-    ?dbg("~p : match_delete(~p, ~p, ~p)", [self(), Alias, Tab, Pat]),
+match_delete(Alias, Tab0, Pat) when is_atom(Pat) ->
+    ?dbg("~p : match_delete(~p, ~p, ~p)", [self(), Alias, Tab0, Pat]),
     %%do_match_delete(Alias, Tab, ?FDB_START),
     case is_wild(Pat) of
         true ->
-            #st{db = Db, table_id = TableId} = mnesia_fdb_manager:st(Tab),
+            #st{db = Db, table_id = TableId} = mnesia_fdb_manager:st(Tab0),
             %% @TODO need to verify if the 'parts' of large values are also removed
             Prefixes = [{TableId},
                         {TableId, ?FDB_WC},
@@ -524,10 +544,10 @@ match_delete(Alias, Tab, Pat) when is_atom(Pat) ->
             ?dbg("is_wild failed on Pat ~p", [Pat]),
             error(badarg)
     end;
-match_delete(_Alias, Tab, Pat) when is_tuple(Pat) ->
-    KP = keypos(Tab),
+match_delete(_Alias, Tab0, Pat) when is_tuple(Pat) ->
+    KP = keypos(Tab0),
     Key = element(KP, Pat),
-    #st{db = Db, table_id = TableId} = St = mnesia_fdb_manager:st(Tab),
+    #st{db = Db, table_id = TableId} = St = mnesia_fdb_manager:st(Tab0),
     case is_wild(Key) of
         true ->
             %% @TODO need to verify if the 'parts' of large values are also removed
@@ -542,9 +562,9 @@ match_delete(_Alias, Tab, Pat) when is_tuple(Pat) ->
     end,
     ok.
 
-first(Alias, Tab) ->
-    ?dbg("~p : first(~p, ~p)", [self(), Alias, Tab]),
-    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab),
+first(Alias, Tab0) ->
+    ?dbg("~p : first(~p, ~p)", [self(), Alias, Tab0]),
+    #st{db = Db, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab0),
     StartKey = sext:prefix({TableId, ?DATA_PREFIX(Type), ?FDB_WC}),
     EndKey = erlfdb_key:strinc(StartKey),
     case erlfdb:get_range(Db, StartKey, EndKey, [{limit,1}]) of
@@ -554,9 +574,9 @@ first(Alias, Tab) ->
             mnesia_fdb_lib:decode_key(EncKey, TableId)
     end.
 
-next(Alias, Tab, Key) ->
-    ?dbg("~p : next(~p, ~p, ~p)", [self(), Alias, Tab, Key]),
-    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab),
+next(Alias, Tab0, Key) ->
+    ?dbg("~p : next(~p, ~p, ~p)", [self(), Alias, Tab0, Key]),
+    #st{db = Db, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab0),
     SKey = sext:encode({TableId, ?DATA_PREFIX(Type), Key}),
     EKey = erlfdb_key:strinc(sext:prefix({TableId, ?DATA_PREFIX(Type), ?FDB_WC})),
     case erlfdb:get_range(Db, SKey, EKey, [{limit, 2}]) of
@@ -575,9 +595,9 @@ next(Alias, Tab, Key) ->
             hd(lists:delete(Key, [Key0, Key1]))
     end.
 
-prev(Alias, Tab, Key) ->
-    ?dbg("~p : prev(~p, ~p, ~p)", [self(), Alias, Tab, Key]),
-    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab),
+prev(Alias, Tab0, Key) ->
+    ?dbg("~p : prev(~p, ~p, ~p)", [self(), Alias, Tab0, Key]),
+    #st{db = Db, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab0),
     SKey = sext:prefix({TableId, ?DATA_PREFIX(Type), ?FDB_WC}),
     EKey = erlfdb_key:strinc(sext:prefix({TableId, ?DATA_PREFIX(Type), Key})),
     case erlfdb:get_range(Db, SKey, EKey, [{reverse, true}, {limit, 2}]) of
@@ -596,9 +616,9 @@ prev(Alias, Tab, Key) ->
             hd(lists:delete(Key, [Key0, Key1]))
     end.
 
-last(Alias, Tab) ->
-    ?dbg("~p : last(~p, ~p)", [self(), Alias, Tab]),
-    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab),
+last(Alias, Tab0) ->
+    ?dbg("~p : last(~p, ~p)", [self(), Alias, Tab0]),
+    #st{db = Db, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab0),
     SKey = sext:prefix({TableId, ?DATA_PREFIX(Type), ?FDB_WC}),
     EKey = erlfdb_key:strinc(SKey),
     case erlfdb:get_range(Db, SKey, EKey, [{reverse, true}, {limit, 1}]) of
@@ -632,9 +652,9 @@ select(Alias, Tab, Ms) ->
             '$end_of_table'
     end.
 
-select(Alias, Tab, Ms, Limit) when is_integer(Limit) ->
-    #st{db = Db, table_id = TableId, tab = Tab, type = Type} = mnesia_fdb_manager:st(Tab),
-    ?dbg("~p : select(~p, ~p, ~p, ~p) mnesia_activity: ~p", [self(),Alias, Tab, Ms, Limit, get(mnesia_activity_state)]),
+select(Alias, Tab0, Ms, Limit) when is_integer(Limit) ->
+    ?dbg("~p : select(~p, ~p, ~p, ~p)", [self(),Alias, Tab0, Ms, Limit]),
+    #st{db = Db, table_id = TableId, tab = Tab, type = Type} = mnesia_fdb_manager:st(Tab0),
     do_select(Db, TableId, Tab, Type, Ms, Limit).
 
 slot(_A, _B, _C) ->
@@ -648,7 +668,7 @@ update_counter(Alias, Tab, Key, Incr) when is_integer(Incr) ->
 
 %% server-side part
 do_update_counter(_Key, _Incr, #st{type = bag}) ->
-    mnesia:abort(counter_not_supported_for_bag);
+    mnesia:abort(badarg);
 do_update_counter(Key, Incr, #st{db = Db, table_id = TableId}) when is_integer(Incr) ->
     %% Atomic counter increment
     %% Mnesia counters are dirty only, and cannot go below zero
@@ -716,11 +736,13 @@ validate_record(_Alias, _Tab, RecName, Arity, Type, _Obj) ->
 %% Extensions for files that are permanent. Needs to be cleaned up
 %% e.g. at deleting the schema.
 real_suffixes() ->
+    ?dbg("~p : real_suffixes()", [self()]),
     [].
 
 %% Extensions for temporary files. Can be cleaned up when mnesia
 %% cleans up other temporary files.
 tmp_suffixes() ->
+    ?dbg("~p : tmp_suffixes()", [self()]),
     [].
 
 
@@ -893,11 +915,6 @@ extract_vars(T) when is_atom(T) ->
 extract_vars(_) ->
     [].
 
-any_in_body(Vars, BodyVars) ->
-    lists:any(fun({_,Vs}) ->
-                      intersection(Vs, BodyVars) =/= []
-              end, Vars).
-
 intersection(A,B) when is_list(A), is_list(B) ->
     A -- (A -- B).
 
@@ -1059,8 +1076,8 @@ decode_val(Db, <<"mfdb_ref", Key/binary>>) ->
 decode_val(_Db, CodedVal) ->
     binary_to_term(CodedVal).
 
-fold(_Alias, Tab, Fun, Acc, MS, N) ->
-    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab),
+fold(_Alias, Tab0, Fun, Acc, MS, N) ->
+    #st{db = Db, tab = Tab, table_id = TableId, type = Type} = mnesia_fdb_manager:st(Tab0),
     do_fold(Db, TableId, Tab, Type, Fun, Acc, MS, N).
 
 %% can be run on the server side.