1 files changed, 70 insertions, 26 deletions

diff --git a/src/fabric/src/fabric2_fdb.erl b/src/fabric/src/fabric2_fdb.erl
index 8bc87926d..403b5bb53 100644
--- a/src/fabric/src/fabric2_fdb.erl
+++ b/src/fabric/src/fabric2_fdb.erl
@@ -89,6 +89,14 @@
     user_acc
 }).
 
+-record(info_future, {
+    tx,
+    db_prefix,
+    changes_future,
+    meta_future,
+    retries = 0
+}).
+
 
 transactional(Fun) ->
     do_transaction(Fun, undefined).
@@ -386,36 +394,37 @@ get_info_future(Tx, DbPrefix) ->
     StatsPrefix = erlfdb_tuple:pack({?DB_STATS}, DbPrefix),
     MetaFuture = erlfdb:get_range_startswith(Tx, StatsPrefix),
 
-    {DbPrefix, ChangesFuture, MetaFuture}.
+    % Save the tx object only if it's read-only as we might retry to get the
+    % future again after the tx was reset
+    SaveTx = case erlfdb:get_writes_allowed(Tx) of
+        true -> undefined;
+        false -> Tx
+    end,
 
+    #info_future{
+        tx = SaveTx,
+        db_prefix = DbPrefix,
+        changes_future = ChangesFuture,
+        meta_future = MetaFuture
+    }.
 
-get_info_wait({DbPrefix, ChangesFuture, MetaFuture}) ->
-    RawSeq = case erlfdb:wait(ChangesFuture) of
-        [] ->
-            vs_to_seq(fabric2_util:seq_zero_vs());
-        [{SeqKey, _}] ->
-            {?DB_CHANGES, SeqVS} = erlfdb_tuple:unpack(SeqKey, DbPrefix),
-            vs_to_seq(SeqVS)
-    end,
-    CProp = {update_seq, RawSeq},
 
-    MProps = lists:foldl(fun({K, V}, Acc) ->
-        case erlfdb_tuple:unpack(K, DbPrefix) of
-            {?DB_STATS, <<"doc_count">>} ->
-                [{doc_count, ?bin2uint(V)} | Acc];
-            {?DB_STATS, <<"doc_del_count">>} ->
-                [{doc_del_count, ?bin2uint(V)} | Acc];
-            {?DB_STATS, <<"sizes">>, Name} ->
-                Val = ?bin2uint(V),
-                {_, {Sizes}} = lists:keyfind(sizes, 1, Acc),
-                NewSizes = lists:keystore(Name, 1, Sizes, {Name, Val}),
-                lists:keystore(sizes, 1, Acc, {sizes, {NewSizes}});
-            {?DB_STATS, _} ->
-                Acc
-        end
-    end, [{sizes, {[]}}], erlfdb:wait(MetaFuture)),
+get_info_wait(#info_future{tx = Tx, retries = Retries} = Future)
+        when Tx =:= undefined orelse Retries >= 2 ->
+    get_info_wait_int(Future);
 
-    [CProp | MProps].
+get_info_wait(#info_future{tx = Tx, retries = Retries} = Future) ->
+    try
+        get_info_wait_int(Future)
+    catch
+        error:{erlfdb_error, ?TRANSACTION_CANCELLED} ->
+            Future1 = get_info_future(Tx, Future#info_future.db_prefix),
+            get_info_wait(Future1#info_future{retries = Retries + 1});
+        error:{erlfdb_error, ?TRANSACTION_TOO_OLD} ->
+            ok = erlfdb:reset(Tx),
+            Future1 = get_info_future(Tx, Future#info_future.db_prefix),
+            get_info_wait(Future1#info_future{retries = Retries + 1})
+    end.
 
 
 load_config(#{} = Db) ->
@@ -1759,6 +1768,41 @@ with_span(Operation, ExtraTags, Fun) ->
     end.
 
 
+get_info_wait_int(#info_future{} = InfoFuture) ->
+    #info_future{
+        db_prefix = DbPrefix,
+        changes_future = ChangesFuture,
+        meta_future = MetaFuture
+    } = InfoFuture,
+
+    RawSeq = case erlfdb:wait(ChangesFuture) of
+        [] ->
+            vs_to_seq(fabric2_util:seq_zero_vs());
+        [{SeqKey, _}] ->
+            {?DB_CHANGES, SeqVS} = erlfdb_tuple:unpack(SeqKey, DbPrefix),
+            vs_to_seq(SeqVS)
+    end,
+    CProp = {update_seq, RawSeq},
+
+    MProps = lists:foldl(fun({K, V}, Acc) ->
+        case erlfdb_tuple:unpack(K, DbPrefix) of
+            {?DB_STATS, <<"doc_count">>} ->
+                [{doc_count, ?bin2uint(V)} | Acc];
+            {?DB_STATS, <<"doc_del_count">>} ->
+                [{doc_del_count, ?bin2uint(V)} | Acc];
+            {?DB_STATS, <<"sizes">>, Name} ->
+                Val = ?bin2uint(V),
+                {_, {Sizes}} = lists:keyfind(sizes, 1, Acc),
+                NewSizes = lists:keystore(Name, 1, Sizes, {Name, Val}),
+                lists:keystore(sizes, 1, Acc, {sizes, {NewSizes}});
+            {?DB_STATS, _} ->
+                Acc
+        end
+    end, [{sizes, {[]}}], erlfdb:wait(MetaFuture)),
+
+    [CProp | MProps].
+
+
 -ifdef(TEST).
 -include_lib("eunit/include/eunit.hrl").