diff options
author | Adam Kocoloski <adam@cloudant.com> | 2010-10-19 17:17:08 -0400 |
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committer | Adam Kocoloski <adam@cloudant.com> | 2010-10-19 17:17:08 -0400 |
commit | ed231d0fd1cf7647cc7a154de81e85cd584bc8b5 (patch) | |
tree | da3c49e4ef1fa06f122ee27c9d2cf3b1a100f92c /apps/fabric | |
parent | 1fc998d21aeb437064324b560f1ac84887e37d6f (diff) |
use new read repair and ancestry checks in fabric:open_doc/3
Diffstat (limited to 'apps/fabric')
-rw-r--r-- | apps/fabric/src/fabric_doc_open.erl | 101 |
1 files changed, 70 insertions, 31 deletions
diff --git a/apps/fabric/src/fabric_doc_open.erl b/apps/fabric/src/fabric_doc_open.erl index 1530515d..9131c94b 100644 --- a/apps/fabric/src/fabric_doc_open.erl +++ b/apps/fabric/src/fabric_doc_open.erl @@ -27,54 +27,93 @@ go(DbName, Id, Options) -> R = couch_util:get_value(r, Options, couch_config:get("cluster","r","2")), Acc0 = {length(Workers), list_to_integer(R), []}, case fabric_util:recv(Workers, #shard.ref, fun handle_message/3, Acc0) of - {ok, {ok, #doc{deleted=true}}} when SuppressDeletedDoc -> - {not_found, deleted}; - {ok, Else} -> - Else; + {ok, Reply} -> + format_reply(Reply, SuppressDeletedDoc); + {error, needs_repair, Reply} -> + spawn(fabric, open_revs, [DbName, Id, all, Options]), + format_reply(Reply, SuppressDeletedDoc); + {error, needs_repair} -> + % we couldn't determine the correct reply, so we'll run a sync repair + {ok, Results} = fabric:open_revs(DbName, Id, all, Options), + case lists:partition(fun({ok, #doc{deleted=Del}}) -> Del end, Results) of + {[], []} -> + {not_found, missing}; + {_DeletedDocs, []} when SuppressDeletedDoc -> + {not_found, deleted}; + {DeletedDocs, []} -> + lists:last(lists:sort(DeletedDocs)); + {_, LiveDocs} -> + lists:last(lists:sort(LiveDocs)) + end; Error -> Error end. +format_reply({ok, #doc{deleted=true}}, true) -> + {not_found, deleted}; +format_reply(Else, _) -> + Else. + handle_message({rexi_DOWN, _, _, _}, _Worker, Acc0) -> skip_message(Acc0); handle_message({rexi_EXIT, _Reason}, _Worker, Acc0) -> skip_message(Acc0); handle_message(Reply, _Worker, {WaitingCount, R, Replies}) -> - case merge_read_reply(make_key(Reply), Reply, Replies) of - {_, KeyCount} when KeyCount =:= R -> - {stop, Reply}; - {NewReplies, KeyCount} when KeyCount < R -> + NewReplies = orddict:update_counter(Reply, 1, Replies), + Reduced = fabric_util:remove_ancestors(NewReplies, []), + case lists:dropwhile(fun({_, Count}) -> Count < R end, Reduced) of + [{QuorumReply, _} | _] -> + if length(NewReplies) =:= 1 -> + {stop, QuorumReply}; + true -> + % we had some disagreement amongst the workers, so repair is useful + {error, needs_repair, QuorumReply} + end; + [] -> if WaitingCount =:= 1 -> - % last message arrived, but still no quorum - repair_read_quorum_failure(NewReplies); + {error, needs_repair}; true -> {ok, {WaitingCount-1, R, NewReplies}} end end. -skip_message({1, _R, Replies}) -> - repair_read_quorum_failure(Replies); +skip_message({1, _R, _Replies}) -> + {error, needs_repair}; skip_message({WaitingCount, R, Replies}) -> {ok, {WaitingCount-1, R, Replies}}. -merge_read_reply(Key, Reply, Replies) -> - case lists:keyfind(Key, 1, Replies) of - false -> - {[{Key, Reply, 1} | Replies], 1}; - {Key, _, N} -> - {lists:keyreplace(Key, 1, Replies, {Key, Reply, N+1}), N+1} - end. -make_key({ok, #doc{id=Id, revs=Revs}}) -> - {Id, Revs}; -make_key(Else) -> - Else. +open_doc_test() -> + Foo1 = {ok, #doc{revs = {1,[<<"foo">>]}}}, + Foo2 = {ok, #doc{revs = {2,[<<"foo2">>,<<"foo">>]}}}, + Bar1 = {ok, #doc{revs = {1,[<<"bar">>]}}}, + Baz1 = {ok, #doc{revs = {1,[<<"baz">>]}}}, + NF = {not_found, missing}, + State0 = {3, 2, []}, + State1 = {2, 2, [{Foo1,1}]}, + State2 = {1, 2, [{Bar1,1}, {Foo1,1}]}, + ?assertEqual({ok, State1}, handle_message(Foo1, nil, State0)), -repair_read_quorum_failure(Replies) -> - case [Doc || {_Key, {ok, Doc}, _Count} <- Replies] of - [] -> - {stop, {not_found, missing}}; - [Doc|_] -> - % TODO merge docs to find the winner as determined by replication - {stop, {ok, Doc}} - end.
\ No newline at end of file + % normal case - quorum reached, no disagreement + ?assertEqual({stop, Foo1}, handle_message(Foo1, nil, State1)), + + % 2nd worker disagrees, voting continues + ?assertEqual({ok, State2}, handle_message(Bar1, nil, State1)), + + % 3rd worker resolves voting, but repair is needed + ?assertEqual({error, needs_repair, Foo1}, handle_message(Foo1, nil, State2)), + + % 2nd worker comes up with descendant of Foo1, voting resolved, run repair + ?assertEqual({error, needs_repair, Foo2}, handle_message(Foo2, nil, State1)), + + % not_found is considered to be an ancestor of everybody + ?assertEqual({error, needs_repair, Foo1}, handle_message(NF, nil, State1)), + + % 3 distinct edit branches result in quorum failure + ?assertEqual({error, needs_repair}, handle_message(Baz1, nil, State2)), + + % bad node concludes voting w/o success, run sync repair to get the result + ?assertEqual( + {error, needs_repair}, + handle_message({rexi_DOWN, 1, 2, 3}, nil, State2) + ). |