Add optional `fields` to change feed selectors
When using selectors with `include_docs=true` can specify an optional fields
array in the POST request JSON body.
Each element in the array can be a json field (or even a key path
specified as field1.field2...). Resulting documents will contain only the
specified document fields.
For example:
```
http://.../d1/_changes?filter=_selector&include_docs=true
{
"selector": {"z" : {"$gte" : 1} }, "fields": ["field1", "field2"]
}
```
Will first select only document with "z" value >= 1, then will return only field1 and field2 in documents.
```{ "field1": "field1value", "field2": "field2value"}```
(This is a companion pr. Main pr is in couch repo)
Jira: COUCHDB-2988
diff --git a/src/fabric_rpc.erl b/src/fabric_rpc.erl
index afe7490..3a21d83 100644
--- a/src/fabric_rpc.erl
+++ b/src/fabric_rpc.erl
@@ -352,20 +352,27 @@
{id, Id},
{changes, Results},
{deleted, Del} |
- if IncludeDocs -> [doc_member(Db, DocInfo, Opts)]; true -> [] end
+ if IncludeDocs -> [doc_member(Db, DocInfo, Opts, Filter)]; true -> [] end
]}
end,
ok = rexi:stream2(ChangesRow),
{ok, Acc#cacc{seq = Seq, pending = Pending-1}}.
-doc_member(Shard, DocInfo, Opts) ->
+doc_member(Shard, DocInfo, Opts, Filter) ->
case couch_db:open_doc(Shard, DocInfo, [deleted | Opts]) of
{ok, Doc} ->
- {doc, couch_doc:to_json_obj(Doc, Opts)};
+ {doc, maybe_filtered_json_doc(Doc, Opts, Filter)};
Error ->
Error
end.
+maybe_filtered_json_doc(Doc, Opts, {selector, _Style, {_Selector, Fields}})
+ when Fields =/= nil ->
+ mango_fields:extract(couch_doc:to_json_obj(Doc, Opts), Fields);
+maybe_filtered_json_doc(Doc, Opts, _Filter) ->
+ couch_doc:to_json_obj(Doc, Opts).
+
+
possible_ancestors(_FullInfo, []) ->
[];
possible_ancestors(FullInfo, MissingRevs) ->
@@ -546,4 +553,19 @@
?assertError(duplicate_epoch, is_owner(foo, 1, [{foo, 1}, {bar, 1}])),
?assertError(epoch_order, is_owner(foo, 1, [{foo, 100}, {bar, 200}])).
+maybe_filtered_json_doc_no_filter_test() ->
+ Body = {[{<<"a">>, 1}]},
+ Doc = #doc{id = <<"1">>, revs = {1, [<<"r1">>]}, body = Body},
+ {JDocProps} = maybe_filtered_json_doc(Doc, [], x),
+ ExpectedProps = [{<<"_id">>, <<"1">>}, {<<"_rev">>, <<"1-r1">>}, {<<"a">>, 1}],
+ ?assertEqual(lists:keysort(1, JDocProps), ExpectedProps).
+
+maybe_filtered_json_doc_with_filter_test() ->
+ Body = {[{<<"a">>, 1}]},
+ Doc = #doc{id = <<"1">>, revs = {1, [<<"r1">>]}, body = Body},
+ Fields = [<<"a">>, <<"nonexistent">>],
+ Filter = {selector, main_only, {some_selector, Fields}},
+ {JDocProps} = maybe_filtered_json_doc(Doc, [], Filter),
+ ?assertEqual(JDocProps, [{<<"a">>, 1}]).
+
-endif.
