This is an automated email from the ASF dual-hosted git repository. davisp pushed a commit to branch COUCHDB-3287-pluggable-storage-engines in repository https://gitbox.apache.org/repos/asf/couchdb.git
commit 6375cd41afed07818ff77713fcab7f7e72e5040c Author: Paul J. Davis <[email protected]> AuthorDate: Wed Feb 8 07:25:37 2017 -0600 Ensure deterministic revisions for attachments This re-fixes a corner case when recreating a document with an attachment in a single multipart request. Since we don't detect that we need a new revision until after the document has been serialized we need to be able to deserialize the body so that we can generate the same revisions regardless of the contents of the database. If we don't do this then we end up including information from the position of the attachment on disk in the revision calculation which can introduce branches in the revision tree. I've left this as a separate commit from the pluggable storage engine work so that its called out clearly for us to revisit. COUCHDB-3255 --- src/couch/src/couch_bt_engine.erl | 10 +++++++++- src/couch/src/couch_db.erl | 12 +----------- src/couch/src/couch_db_updater.erl | 12 +++++++++++- 3 files changed, 21 insertions(+), 13 deletions(-) diff --git a/src/couch/src/couch_bt_engine.erl b/src/couch/src/couch_bt_engine.erl index e7178d1..0680ffd 100644 --- a/src/couch/src/couch_bt_engine.erl +++ b/src/couch/src/couch_bt_engine.erl @@ -325,7 +325,15 @@ serialize_doc(#st{} = St, #doc{} = Doc) -> SummaryBin = ?term_to_bin({Body, Atts}), Md5 = couch_crypto:hash(md5, SummaryBin), Data = couch_file:assemble_file_chunk(SummaryBin, Md5), - Doc#doc{body = Data}. + % TODO: This is a terrible hack to get around the issues + % in COUCHDB-3255. We'll need to come back and figure + % out a better approach to handling the case when we + % need to generate a new revision id after the doc + % has been serialized. + Doc#doc{ + body = Data, + meta = [{comp_body, Body} | Doc#doc.meta] + }. write_doc_body(St, #doc{} = Doc) -> diff --git a/src/couch/src/couch_db.erl b/src/couch/src/couch_db.erl index 95a14a1..5018d25 100644 --- a/src/couch/src/couch_db.erl +++ b/src/couch/src/couch_db.erl @@ -942,7 +942,7 @@ prep_and_validate_replicated_updates(Db, [Bucket|RestBuckets], [OldInfo|RestOldI -new_revid(#doc{body=Body0, revs={OldStart,OldRevs}, atts=Atts, deleted=Deleted}) -> +new_revid(#doc{body=Body, revs={OldStart,OldRevs}, atts=Atts, deleted=Deleted}) -> DigestedAtts = lists:foldl(fun(Att, Acc) -> [N, T, M] = couch_att:fetch([name, type, md5], Att), case M == <<>> of @@ -950,16 +950,6 @@ new_revid(#doc{body=Body0, revs={OldStart,OldRevs}, atts=Atts, deleted=Deleted}) false -> [{N, T, M} | Acc] end end, [], Atts), - Body = case Body0 of - {summary, [_Len, _Md5, BodyAtts], _SizeInfo, _AttsFd} -> - {CompBody, _CompAtts} = binary_to_term(BodyAtts), - couch_compress:decompress(CompBody); - {summary, [_Len, BodyAtts], _SizeInfo, _AttsFd} -> - {CompBody, _CompAtts} = binary_to_term(BodyAtts), - couch_compress:decompress(CompBody); - Else -> - Else - end, case DigestedAtts of Atts2 when length(Atts) =/= length(Atts2) -> % We must have old style non-md5 attachments diff --git a/src/couch/src/couch_db_updater.erl b/src/couch/src/couch_db_updater.erl index dbf3a6e..dd5b4e7 100644 --- a/src/couch/src/couch_db_updater.erl +++ b/src/couch/src/couch_db_updater.erl @@ -525,7 +525,17 @@ merge_rev_tree(OldInfo, NewDoc, Client, Limit, false) % Update the new doc based on revisions in OldInfo #doc_info{revs=[WinningRev | _]} = couch_doc:to_doc_info(OldInfo), #rev_info{rev={OldPos, OldRev}} = WinningRev, - NewRevId = couch_db:new_revid(NewDoc#doc{revs={OldPos, [OldRev]}}), + Body = case couch_util:get_value(comp_body, NewDoc#doc.meta) of + CompBody when is_binary(CompBody) -> + couch_compress:decompress(CompBody); + _ -> + NewDoc#doc.body + end, + RevIdDoc = NewDoc#doc{ + revs = {OldPos, [OldRev]}, + body = Body + }, + NewRevId = couch_db:new_revid(RevIdDoc), NewDoc2 = NewDoc#doc{revs={OldPos + 1, [NewRevId, OldRev]}}, % Merge our modified new doc into the tree -- To stop receiving notification emails like this one, please contact "[email protected]" <[email protected]>.
