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Posted to commits@couchdb.apache.org by da...@apache.org on 2019/05/20 18:03:52 UTC
[couchdb] 05/05: Implement get_missing_revs
This is an automated email from the ASF dual-hosted git repository.
davisp pushed a commit to branch prototype/rfc-001-revision-metadata-model
in repository https://gitbox.apache.org/repos/asf/couchdb.git
commit bb3ed4cca8b8280745f6315dfc43aa4fe34b04ff
Author: Paul J. Davis <pa...@gmail.com>
AuthorDate: Mon May 20 13:01:42 2019 -0500
Implement get_missing_revs
---
src/chttpd/src/chttpd_db.erl | 4 +-
src/fabric/src/fabric2_db.erl | 82 +++++++++++++++++++++++++++++-
src/fabric/test/fabric2_doc_crud_tests.erl | 51 ++++++++++++++++++-
3 files changed, 133 insertions(+), 4 deletions(-)
diff --git a/src/chttpd/src/chttpd_db.erl b/src/chttpd/src/chttpd_db.erl
index c0c7ad3..27c1a8a 100644
--- a/src/chttpd/src/chttpd_db.erl
+++ b/src/chttpd/src/chttpd_db.erl
@@ -674,7 +674,7 @@ db_req(#httpd{path_parts=[_,OP]}=Req, _Db) when ?IS_ALL_DOCS(OP) ->
db_req(#httpd{method='POST',path_parts=[_,<<"_missing_revs">>]}=Req, Db) ->
chttpd:validate_ctype(Req, "application/json"),
{JsonDocIdRevs} = chttpd:json_body_obj(Req),
- case fabric:get_missing_revs(Db, JsonDocIdRevs) of
+ case fabric2_db:get_missing_revs(Db, JsonDocIdRevs) of
{error, Reason} ->
chttpd:send_error(Req, Reason);
{ok, Results} ->
@@ -691,7 +691,7 @@ db_req(#httpd{path_parts=[_,<<"_missing_revs">>]}=Req, _Db) ->
db_req(#httpd{method='POST',path_parts=[_,<<"_revs_diff">>]}=Req, Db) ->
chttpd:validate_ctype(Req, "application/json"),
{JsonDocIdRevs} = chttpd:json_body_obj(Req),
- case fabric:get_missing_revs(Db, JsonDocIdRevs) of
+ case fabric2_db:get_missing_revs(Db, JsonDocIdRevs) of
{error, Reason} ->
chttpd:send_error(Req, Reason);
{ok, Results} ->
diff --git a/src/fabric/src/fabric2_db.erl b/src/fabric/src/fabric2_db.erl
index 68de40c..a9c17c9 100644
--- a/src/fabric/src/fabric2_db.erl
+++ b/src/fabric/src/fabric2_db.erl
@@ -73,7 +73,7 @@
%% get_doc_info/2,
%% get_full_doc_info/2,
%% get_full_doc_infos/2,
- %% get_missing_revs/2,
+ get_missing_revs/2,
%% get_design_doc/2,
%% get_design_docs/1,
%% get_design_doc_count/1,
@@ -461,6 +461,38 @@ open_doc_revs(Db, DocId, Revs, Options) ->
end).
+get_missing_revs(Db, IdRevs) ->
+ AllRevInfos = fabric2_fdb:transactional(Db, fun(TxDb) ->
+ lists:foldl(fun({Id, _Revs}, Acc) ->
+ case maps:is_key(Id, Acc) of
+ true ->
+ Acc;
+ false ->
+ RevInfos = fabric2_fdb:get_all_revs(TxDb, Id),
+ Acc#{Id => RevInfos}
+ end
+ end, #{}, IdRevs)
+ end),
+ AllMissing = lists:flatmap(fun({Id, Revs}) ->
+ #{Id := RevInfos} = AllRevInfos,
+ Missing = try
+ lists:foldl(fun(RevInfo, RevAcc) ->
+ if RevAcc /= [] -> ok; true ->
+ throw(all_found)
+ end,
+ filter_found_revs(RevInfo, RevAcc)
+ end, Revs, RevInfos)
+ catch throw:all_found ->
+ []
+ end,
+ if Missing == [] -> []; true ->
+ PossibleAncestors = find_possible_ancestors(RevInfos, Missing),
+ [{Id, Missing, PossibleAncestors}]
+ end
+ end, IdRevs),
+ {ok, AllMissing}.
+
+
update_doc(Db, Doc) ->
update_doc(Db, Doc, []).
@@ -700,6 +732,54 @@ apply_open_doc_opts(Doc, Revs, Options) ->
end.
+filter_found_revs(RevInfo, Revs) ->
+ #{
+ rev_id := {Pos, Rev},
+ rev_path := RevPath
+ } = RevInfo,
+ FullRevPath = [Rev | RevPath],
+ lists:flatmap(fun({FindPos, FindRev} = RevIdToFind) ->
+ if FindPos > Pos -> [RevIdToFind]; true ->
+ % Add 1 because lists:nth is 1 based
+ Idx = Pos - FindPos + 1,
+ case Idx > length(FullRevPath) of
+ true ->
+ [RevIdToFind];
+ false ->
+ case lists:nth(Idx, FullRevPath) == FindRev of
+ true -> [];
+ false -> [RevIdToFind]
+ end
+ end
+ end
+ end, Revs).
+
+
+find_possible_ancestors(RevInfos, MissingRevs) ->
+ % Find any revinfos that are possible ancestors
+ % of the missing revs. A possible ancestor is
+ % any rev that has a start position less than
+ % any missing revision. Stated alternatively,
+ % find any revinfo that could theoretically
+ % extended to be one or more of the missing
+ % revisions.
+ %
+ % Since we are looking at any missing revision
+ % we can just compare against the maximum missing
+ % start position.
+ MaxMissingPos = case MissingRevs of
+ [] -> 0;
+ [_ | _] -> lists:max([Start || {Start, _Rev} <- MissingRevs])
+ end,
+ lists:flatmap(fun(RevInfo) ->
+ #{rev_id := {RevPos, _} = RevId} = RevInfo,
+ case RevPos < MaxMissingPos of
+ true -> [RevId];
+ false -> []
+ end
+ end, RevInfos).
+
+
update_doc_int(#{} = Db, #doc{} = Doc, Options) ->
IsLocal = case Doc#doc.id of
<<?LOCAL_DOC_PREFIX, _/binary>> -> true;
diff --git a/src/fabric/test/fabric2_doc_crud_tests.erl b/src/fabric/test/fabric2_doc_crud_tests.erl
index 86dbcc8..17e8c36 100644
--- a/src/fabric/test/fabric2_doc_crud_tests.erl
+++ b/src/fabric/test/fabric2_doc_crud_tests.erl
@@ -52,6 +52,7 @@ doc_crud_test_() ->
fun open_doc_revs_basic/1,
fun open_doc_revs_all/1,
fun open_doc_revs_latest/1,
+ fun get_missing_revs_basic/1,
fun open_missing_local_doc/1,
fun create_local_doc_basic/1,
fun update_local_doc_basic/1,
@@ -347,7 +348,7 @@ delete_doc_basic({Db, _}) ->
},
{ok, {Pos2, Rev2}} = fabric2_db:update_doc(Db, Doc2),
Doc3 = Doc2#doc{revs = {Pos2, [Rev2, Rev1]}},
- ?assertEqual({ok, Doc3}, fabric2_db:open_doc(Db, Doc2#doc.id)).
+ ?assertEqual({ok, Doc3}, fabric2_db:open_doc(Db, Doc2#doc.id, [deleted])).
delete_changes_winner({Db, _}) ->
@@ -566,6 +567,54 @@ open_doc_revs_latest({Db, _}) ->
?assert(lists:member({ok, Doc2}, Docs)).
+get_missing_revs_basic({Db, _}) ->
+ [Rev1, Rev2, Rev3] = lists:sort([
+ fabric2_util:uuid(),
+ fabric2_util:uuid(),
+ fabric2_util:uuid()
+ ]),
+ DocId = fabric2_util:uuid(),
+ Doc1 = #doc{
+ id = DocId,
+ revs = {2, [Rev3, Rev1]},
+ body = {[{<<"foo">>, <<"bar">>}]}
+ },
+ {ok, {2, _}} = fabric2_db:update_doc(Db, Doc1, [replicated_changes]),
+ Doc2 = Doc1#doc{
+ revs = {2, [Rev2, Rev1]},
+ body = {[{<<"bar">>, <<"foo">>}]}
+ },
+ {ok, {2, _}} = fabric2_db:update_doc(Db, Doc2, [replicated_changes]),
+
+ % Check that we can find all revisions
+ AllRevs = [{1, Rev1}, {2, Rev2}, {2, Rev3}],
+ ?assertEqual(
+ {ok, []},
+ fabric2_db:get_missing_revs(Db, [{DocId, AllRevs}])
+ ),
+
+ % Check that a missing revision is found with no possible ancestors
+ MissingRev = {2, fabric2_util:uuid()},
+ ?assertEqual(
+ {ok, [{DocId, [MissingRev], []}]},
+ fabric2_db:get_missing_revs(Db, [{DocId, [MissingRev]}])
+ ),
+
+ % Check that only a missing rev is returned
+ ?assertEqual(
+ {ok, [{DocId, [MissingRev], []}]},
+ fabric2_db:get_missing_revs(Db, [{DocId, [MissingRev | AllRevs]}])
+ ),
+
+ % Check that we can find possible ancestors
+ MissingWithAncestors = {4, fabric2_util:uuid()},
+ PossibleAncestors = [{2, Rev2}, {2, Rev3}],
+ ?assertEqual(
+ {ok, [{DocId, [MissingWithAncestors], PossibleAncestors}]},
+ fabric2_db:get_missing_revs(Db, [{DocId, [MissingWithAncestors]}])
+ ).
+
+
open_missing_local_doc({Db, _}) ->
?assertEqual(
{not_found, missing},