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 87441f8023dd4f9fc28243621e1e4cc9a625e7f3 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 374199f..0cd9d65 100644 --- a/src/couch/src/couch_bt_engine.erl +++ b/src/couch/src/couch_bt_engine.erl @@ -324,7 +324,15 @@ 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 2f581bd..70e4c32 100644 --- a/src/couch/src/couch_db.erl +++ b/src/couch/src/couch_db.erl @@ -943,7 +943,7 @@ 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 @@ -951,16 +951,6 @@ 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 459a5e6..2e6bf29 100644 --- a/src/couch/src/couch_db_updater.erl +++ b/src/couch/src/couch_db_updater.erl @@ -526,7 +526,17 @@ 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]>.
