github.com/m3db/m3@v1.5.0/src/m3ninx/search/searcher/disjunction.go (about)

     1  // Copyright (c) 2018 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package searcher
    22  
    23  import (
    24  	"github.com/m3db/m3/src/m3ninx/index"
    25  	"github.com/m3db/m3/src/m3ninx/postings"
    26  	"github.com/m3db/m3/src/m3ninx/postings/roaring"
    27  	"github.com/m3db/m3/src/m3ninx/search"
    28  )
    29  
    30  type disjunctionSearcher struct {
    31  	searchers search.Searchers
    32  }
    33  
    34  // NewDisjunctionSearcher returns a new Searcher which matches documents which are matched
    35  // by any of the given Searchers.
    36  func NewDisjunctionSearcher(searchers search.Searchers) (search.Searcher, error) {
    37  	if len(searchers) == 0 {
    38  		return nil, errEmptySearchers
    39  	}
    40  
    41  	return &disjunctionSearcher{
    42  		searchers: searchers,
    43  	}, nil
    44  }
    45  
    46  func (s *disjunctionSearcher) Search(r index.Reader) (postings.List, error) {
    47  	lists := make([]postings.List, 0, len(s.searchers))
    48  	for _, sr := range s.searchers {
    49  		curr, err := sr.Search(r)
    50  		if err != nil {
    51  			return nil, err
    52  		}
    53  		lists = append(lists, curr)
    54  	}
    55  
    56  	return roaring.Union(lists)
    57  }