| % Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| % use this file except in compliance with the License. You may obtain a copy of |
| % the License at |
| % |
| % http://www.apache.org/licenses/LICENSE-2.0 |
| % |
| % Unless required by applicable law or agreed to in writing, software |
| % distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| % WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| % License for the specific language governing permissions and limitations under |
| % the License. |
| |
| -module(mango_idx_special). |
| |
| -export([ |
| validate/1, |
| add/2, |
| remove/2, |
| from_ddoc/1, |
| to_json/1, |
| columns/1, |
| is_usable/3, |
| start_key/1, |
| end_key/1 |
| ]). |
| |
| -include_lib("couch/include/couch_db.hrl"). |
| -include("mango.hrl"). |
| |
| validate(_) -> |
| erlang:exit(invalid_call). |
| |
| add(_, _) -> |
| erlang:exit(invalid_call). |
| |
| remove(_, _) -> |
| erlang:exit(invalid_call). |
| |
| from_ddoc(_) -> |
| erlang:exit(invalid_call). |
| |
| to_json(#idx{def = all_docs}) -> |
| {[ |
| {ddoc, null}, |
| {name, <<"_all_docs">>}, |
| {type, <<"special">>}, |
| {def, |
| {[ |
| {<<"fields">>, [ |
| {[ |
| {<<"_id">>, <<"asc">>} |
| ]} |
| ]} |
| ]}} |
| ]}. |
| |
| columns(#idx{def = all_docs}) -> |
| [<<"_id">>]. |
| |
| is_usable(#idx{def = all_docs}, _Selector, []) -> |
| {true, #{reason => []}}; |
| is_usable(#idx{def = all_docs} = Idx, Selector, SortFields) -> |
| Fields = mango_idx_view:indexable_fields(Selector), |
| SelectorHasRequiredFields = lists:member(<<"_id">>, Fields), |
| CanUseSort = can_use_sort(Idx, SortFields, Selector), |
| Reason = |
| [field_mismatch || not SelectorHasRequiredFields] ++ |
| [sort_order_mismatch || not CanUseSort], |
| Details = #{reason => Reason}, |
| {SelectorHasRequiredFields and CanUseSort, Details}. |
| |
| start_key([{'$gt', Key, _, _}]) -> |
| case mango_json:special(Key) of |
| true -> |
| ?MIN_STR; |
| false -> |
| Key |
| end; |
| start_key([{'$gte', Key, _, _}]) -> |
| false = mango_json:special(Key), |
| Key; |
| start_key([{'$eq', Key, '$eq', Key}]) -> |
| false = mango_json:special(Key), |
| Key. |
| |
| end_key([{_, _, '$lt', Key}]) -> |
| case mango_json:special(Key) of |
| true -> |
| ?MAX_STR; |
| false -> |
| Key |
| end; |
| end_key([{_, _, '$lte', Key}]) -> |
| false = mango_json:special(Key), |
| Key; |
| end_key([{'$eq', Key, '$eq', Key}]) -> |
| false = mango_json:special(Key), |
| Key. |
| |
| can_use_sort(_Idx, [], _Selector) -> |
| true; |
| can_use_sort(Idx, SortFields, _Selector) -> |
| Cols = columns(Idx), |
| lists:prefix(SortFields, Cols). |
| |
| -ifdef(TEST). |
| -include_lib("couch/include/couch_eunit.hrl"). |
| |
| usable(Index, undefined, Fields) -> |
| is_usable(Index, undefined, Fields); |
| usable(Index, Selector, Fields) -> |
| is_usable(Index, test_util:as_selector(Selector), Fields). |
| |
| is_usable_test() -> |
| Usable = {true, #{reason => []}}, |
| FieldMismatch = {false, #{reason => [field_mismatch]}}, |
| SortOrderMismatch = {false, #{reason => [sort_order_mismatch]}}, |
| |
| Index = #idx{def = all_docs}, |
| ?assertEqual(FieldMismatch, usable(Index, #{}, [<<"_id">>])), |
| ?assertEqual(SortOrderMismatch, usable(Index, #{<<"_id">> => 11}, [<<"field3">>])), |
| ?assertEqual(Usable, usable(Index, #{}, [])). |
| -endif. |