Make get_security and get_revs_limit calls consistent

There are two fixes:

1) In `fabric2_fdb:get_config/1`, Db was matched before and after
`ensure_current/1`. Only the db prefix path was used, which doesn't normally
change, but it's worth fixing it anyway.

2) We used a cached version of the security document outside the transaction.
Now we force it go through a transaction to call `fabric2_fdb:get_config/1`
which call `ensure_current/1`. When done, we also update the cached Db handle.
Do the same thing for revs_limit even thought it is not as critical as
security.

3 files changed, 45 insertions, 23 deletions

diff --git a/src/fabric/src/fabric2_db.erl b/src/fabric/src/fabric2_db.erl
index 853b5021a..8927ce365 100644
--- a/src/fabric/src/fabric2_db.erl
+++ b/src/fabric/src/fabric2_db.erl
@@ -346,12 +346,18 @@ get_pid(#{}) ->
     nil.
 
 
-get_revs_limit(#{revs_limit := RevsLimit}) ->
-    RevsLimit.
+get_revs_limit(#{} = Db) ->
+    RevsLimitBin = fabric2_fdb:transactional(Db, fun(TxDb) ->
+        fabric2_fdb:get_config(TxDb, <<"revs_limit">>)
+    end),
+    ?bin2uint(RevsLimitBin).
 
 
-get_security(#{security_doc := SecurityDoc}) ->
-    SecurityDoc.
+get_security(#{} = Db) ->
+    SecBin = fabric2_fdb:transactional(Db, fun(TxDb) ->
+        fabric2_fdb:get_config(TxDb, <<"security_doc">>)
+    end),
+    ?JSON_DECODE(SecBin).
 
 
 get_update_seq(#{} = Db) ->
diff --git a/src/fabric/src/fabric2_fdb.erl b/src/fabric/src/fabric2_fdb.erl
index 391122ee3..ccfeb3c06 100644
--- a/src/fabric/src/fabric2_fdb.erl
+++ b/src/fabric/src/fabric2_fdb.erl
@@ -28,6 +28,7 @@
 
     get_info/1,
     get_config/1,
+    get_config/2,
     set_config/3,
 
     get_stat/2,
@@ -338,7 +339,7 @@ get_config(#{} = Db) ->
     #{
         tx := Tx,
         db_prefix := DbPrefix
-    } = Db = ensure_current(Db),
+    } = ensure_current(Db),
 
     {Start, End} = erlfdb_tuple:range({?DB_CONFIG}, DbPrefix),
     Future = erlfdb:get_range(Tx, Start, End),
@@ -349,6 +350,19 @@ get_config(#{} = Db) ->
     end, erlfdb:wait(Future)).
 
 
+get_config(#{} = Db, ConfigKey) ->
+    #{
+        tx := Tx,
+        db_prefix := DbPrefix
+    } = ensure_current(Db),
+
+    Key = erlfdb_tuple:pack({?DB_CONFIG, ConfigKey}, DbPrefix),
+    case erlfdb:wait(erlfdb:get(Tx, Key)) of
+        % config values are expected to be set so we blow if not_found
+        Val when Val =/= not_found -> Val
+    end.
+
+
 set_config(#{} = Db, ConfigKey, ConfigVal) ->
     #{
         tx := Tx,
diff --git a/src/fabric/test/fabric2_db_security_tests.erl b/src/fabric/test/fabric2_db_security_tests.erl
index 979601167..b4df3b4dd 100644
--- a/src/fabric/test/fabric2_db_security_tests.erl
+++ b/src/fabric/test/fabric2_db_security_tests.erl
@@ -47,6 +47,7 @@ security_test_() ->
 setup() ->
     Ctx = test_util:start_couch([fabric]),
     DbName = ?tempdb(),
+    PubDbName = ?tempdb(),
     {ok, Db1} = fabric2_db:create(DbName, [{user_ctx, ?ADMIN_USER}]),
     SecProps = {[
         {<<"admins">>, {[
@@ -60,40 +61,42 @@ setup() ->
     ]},
     ok = fabric2_db:set_security(Db1, SecProps),
     {ok, Db2} = fabric2_db:open(DbName, []),
-    {Db2, Ctx}.
+    {ok, PubDb} = fabric2_db:create(PubDbName, []),
+    {Db2, PubDb, Ctx}.
 
 
-cleanup({Db, Ctx}) ->
+cleanup({Db, PubDb, Ctx}) ->
     ok = fabric2_db:delete(fabric2_db:name(Db), []),
+    ok = fabric2_db:delete(fabric2_db:name(PubDb), []),
     test_util:stop_couch(Ctx).
 
 
-is_admin_name({Db, _}) ->
+is_admin_name({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"admin_name1">>},
     ?assertEqual(true, fabric2_db:is_admin(Db#{user_ctx := UserCtx})).
 
 
-is_not_admin_name({Db, _}) ->
+is_not_admin_name({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"member1">>},
     ?assertEqual(false, fabric2_db:is_admin(Db#{user_ctx := UserCtx})).
 
 
-is_admin_role({Db, _}) ->
+is_admin_role({Db, _, _}) ->
     UserCtx = #user_ctx{roles = [<<"admin_role1">>]},
     ?assertEqual(true, fabric2_db:is_admin(Db#{user_ctx := UserCtx})).
 
 
-is_not_admin_role({Db, _}) ->
+is_not_admin_role({Db, _, _}) ->
     UserCtx = #user_ctx{roles = [<<"member_role1">>]},
     ?assertEqual(false, fabric2_db:is_admin(Db#{user_ctx := UserCtx})).
 
 
-check_is_admin({Db, _}) ->
+check_is_admin({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"admin_name1">>},
     ?assertEqual(ok, fabric2_db:check_is_admin(Db#{user_ctx := UserCtx})).
 
 
-check_is_not_admin({Db, _}) ->
+check_is_not_admin({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"member_name1">>},
     ?assertThrow(
         {unauthorized, <<"You are not a db or server admin.">>},
@@ -105,12 +108,12 @@ check_is_not_admin({Db, _}) ->
     ).
 
 
-check_is_member_name({Db, _}) ->
+check_is_member_name({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"member_name1">>},
     ?assertEqual(ok, fabric2_db:check_is_member(Db#{user_ctx := UserCtx})).
 
 
-check_is_not_member_name({Db, _}) ->
+check_is_not_member_name({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"foo">>},
     ?assertThrow(
         {unauthorized, <<"You are not authorized", _/binary>>},
@@ -122,12 +125,12 @@ check_is_not_member_name({Db, _}) ->
     ).
 
 
-check_is_member_role({Db, _}) ->
+check_is_member_role({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"foo">>, roles = [<<"member_role1">>]},
     ?assertEqual(ok, fabric2_db:check_is_member(Db#{user_ctx := UserCtx})).
 
 
-check_is_not_member_role({Db, _}) ->
+check_is_not_member_role({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"foo">>, roles = [<<"bar">>]},
     ?assertThrow(
         {forbidden, <<"You are not allowed to access", _/binary>>},
@@ -135,25 +138,24 @@ check_is_not_member_role({Db, _}) ->
     ).
 
 
-check_admin_is_member({Db, _}) ->
+check_admin_is_member({Db, _, _}) ->
     UserCtx = #user_ctx{name = <<"admin_name1">>},
     ?assertEqual(ok, fabric2_db:check_is_member(Db#{user_ctx := UserCtx})).
 
 
-check_is_member_of_public_db({Db, _}) ->
-    PublicDb = Db#{security_doc := {[]}},
+check_is_member_of_public_db({_, PubDb, _}) ->
     UserCtx = #user_ctx{name = <<"foo">>, roles = [<<"bar">>]},
     ?assertEqual(
         ok,
-        fabric2_db:check_is_member(PublicDb#{user_ctx := #user_ctx{}})
+        fabric2_db:check_is_member(PubDb#{user_ctx := #user_ctx{}})
     ),
     ?assertEqual(
         ok,
-        fabric2_db:check_is_member(PublicDb#{user_ctx := UserCtx})
+        fabric2_db:check_is_member(PubDb#{user_ctx := UserCtx})
     ).
 
 
-check_set_user_ctx({Db0, _}) ->
+check_set_user_ctx({Db0, _, _}) ->
     DbName = fabric2_db:name(Db0),
     UserCtx = #user_ctx{name = <<"foo">>, roles = [<<"bar">>]},
     {ok, Db1} = fabric2_db:open(DbName, [{user_ctx, UserCtx}]),