Ensure valid seq is returned in changes feed When nodes go down whilst continuous replications are running sequences with incomplete ranges are returned, which creates havoc if they get into chekpoints. This patch makes a final call to is_progress_possible and errors out if an invalid sequence would be returned.
BugzID: 17240 BugzID: 16415 Project: http://git-wip-us.apache.org/repos/asf/couchdb-fabric/repo Commit: http://git-wip-us.apache.org/repos/asf/couchdb-fabric/commit/8e72cf76 Tree: http://git-wip-us.apache.org/repos/asf/couchdb-fabric/tree/8e72cf76 Diff: http://git-wip-us.apache.org/repos/asf/couchdb-fabric/diff/8e72cf76 Branch: refs/heads/import Commit: 8e72cf7617d4dee3cb676d612c509fc20d463f7d Parents: 0158038 Author: Bob Dionne <b...@cloudant.com> Authored: Wed Feb 20 12:51:35 2013 -0500 Committer: Bob Dionne <b...@cloudant.com> Committed: Thu Feb 21 06:12:49 2013 -0500 ---------------------------------------------------------------------- src/fabric_view.erl | 3 ++- src/fabric_view_changes.erl | 30 ++++++++++++++++++++++++------ 2 files changed, 26 insertions(+), 7 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/couchdb-fabric/blob/8e72cf76/src/fabric_view.erl ---------------------------------------------------------------------- diff --git a/src/fabric_view.erl b/src/fabric_view.erl index 63ab3f4..d769f9c 100644 --- a/src/fabric_view.erl +++ b/src/fabric_view.erl @@ -31,7 +31,8 @@ remove_down_shards(Collector, BadNode) -> {ok, Collector#collector{counters = NewCounters}}; error -> Reason = {nodedown, <<"progress not possible">>}, - Callback({error, Reason}, Acc) + Callback({error, Reason}, Acc), + {stop, Collector} end. %% @doc looks for a fully covered keyrange in the list of counters http://git-wip-us.apache.org/repos/asf/couchdb-fabric/blob/8e72cf76/src/fabric_view_changes.erl ---------------------------------------------------------------------- diff --git a/src/fabric_view_changes.erl b/src/fabric_view_changes.erl index 8843562..817bbf7 100644 --- a/src/fabric_view_changes.erl +++ b/src/fabric_view_changes.erl @@ -183,16 +183,26 @@ handle_message(#change{key=Seq} = Row0, {Worker, From}, St) -> _ -> S1 = fabric_dict:store(Worker, Seq, S0), S2 = fabric_view:remove_overlapping_shards(Worker, S1), - Row = Row0#change{key = pack_seqs(S2)}, - {Go, Acc} = Callback(changes_row(Row, IncludeDocs), AccIn), - gen_server:reply(From, Go), - {Go, St#collector{counters=S2, limit=Limit-1, user_acc=Acc}} + case fabric_view:is_progress_possible(S2) of + true -> + Row = Row0#change{key = pack_seqs(S2)}, + {Go, Acc} = Callback(changes_row(Row, IncludeDocs), AccIn), + gen_server:reply(From, Go), + {Go, St#collector{counters=S2, limit=Limit-1, user_acc=Acc}}; + false -> + Reason = {range_not_covered, <<"progress not possible">>}, + Callback({error, Reason}, AccIn), + gen_server:reply(From, stop), + {stop, St#collector{counters=S2}} + end end; handle_message({complete, EndSeq}, Worker, State) -> #collector{ + callback = Callback, counters = S0, - total_rows = Completed % override + total_rows = Completed, % override + user_acc = Acc } = State, case fabric_dict:lookup_element(Worker, S0) of undefined -> @@ -204,7 +214,15 @@ handle_message({complete, EndSeq}, Worker, State) -> NewState = State#collector{counters=S2, total_rows=Completed+1}, case fabric_dict:size(S2) =:= (Completed+1) of true -> - {stop, NewState}; + % final check ranges are covered + case fabric_view:is_progress_possible(S2) of + true -> + {stop, NewState}; + false -> + Reason = {range_not_covered, <<"progress not possible">>}, + Callback({error, Reason}, Acc), + {stop, NewState} + end; false -> {ok, NewState} end
