github.com/m3db/m3@v1.5.0/src/m3ninx/search/query/regexp.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 query
    22  
    23  import (
    24  	"bytes"
    25  	"strings"
    26  
    27  	"github.com/m3db/m3/src/m3ninx/generated/proto/querypb"
    28  	"github.com/m3db/m3/src/m3ninx/index"
    29  	"github.com/m3db/m3/src/m3ninx/search"
    30  	"github.com/m3db/m3/src/m3ninx/search/searcher"
    31  )
    32  
    33  // RegexpQuery finds documents which match the given regular expression.
    34  type RegexpQuery struct {
    35  	str      string
    36  	field    []byte
    37  	regexp   []byte
    38  	compiled index.CompiledRegex
    39  }
    40  
    41  // NewRegexpQuery constructs a new query for the given regular expression.
    42  func NewRegexpQuery(field, regexp []byte) (search.Query, error) {
    43  	compiled, err := index.CompileRegex(regexp)
    44  	if err != nil {
    45  		return nil, err
    46  	}
    47  
    48  	q := &RegexpQuery{
    49  		field:    field,
    50  		regexp:   regexp,
    51  		compiled: compiled,
    52  	}
    53  	// NB(r): Calculate string value up front so
    54  	// not allocated every time String() is called to determine
    55  	// the cache key.
    56  	q.str = q.string()
    57  	return q, nil
    58  }
    59  
    60  // MustCreateRegexpQuery is like NewRegexpQuery but panics if the query cannot be created.
    61  func MustCreateRegexpQuery(field, regexp []byte) search.Query {
    62  	q, err := NewRegexpQuery(field, regexp)
    63  	if err != nil {
    64  		panic(err)
    65  	}
    66  	return q
    67  }
    68  
    69  // Searcher returns a searcher over the provided readers.
    70  func (q *RegexpQuery) Searcher() (search.Searcher, error) {
    71  	return searcher.NewRegexpSearcher(q.field, q.compiled), nil
    72  }
    73  
    74  // Equal reports whether q is equivalent to o.
    75  func (q *RegexpQuery) Equal(o search.Query) bool {
    76  	o, ok := singular(o)
    77  	if !ok {
    78  		return false
    79  	}
    80  
    81  	inner, ok := o.(*RegexpQuery)
    82  	if !ok {
    83  		return false
    84  	}
    85  
    86  	return bytes.Equal(q.field, inner.field) && bytes.Equal(q.regexp, inner.regexp)
    87  }
    88  
    89  // ToProto returns the Protobuf query struct corresponding to the regexp query.
    90  func (q *RegexpQuery) ToProto() *querypb.Query {
    91  	regexp := querypb.RegexpQuery{
    92  		Field:  q.field,
    93  		Regexp: q.regexp,
    94  	}
    95  
    96  	return &querypb.Query{
    97  		Query: &querypb.Query_Regexp{Regexp: &regexp},
    98  	}
    99  }
   100  
   101  func (q *RegexpQuery) String() string {
   102  	return q.str
   103  }
   104  
   105  func (q *RegexpQuery) string() string {
   106  	var str strings.Builder
   107  	str.WriteString("regexp(")
   108  	str.Write(q.field)
   109  	str.WriteRune(',')
   110  	str.Write(q.regexp)
   111  	str.WriteRune(')')
   112  	return str.String()
   113  }