github.com/m3db/m3@v1.5.0/src/query/graphite/storage/converter.go (about)

     1  // Copyright (c) 2019 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 storage
    22  
    23  import (
    24  	"github.com/m3db/m3/src/query/graphite/graphite"
    25  	"github.com/m3db/m3/src/query/models"
    26  )
    27  
    28  const (
    29  	wildcard = "*"
    30  )
    31  
    32  func convertMetricPartToMatcher(
    33  	count int,
    34  	metric string,
    35  ) (models.Matcher, error) {
    36  	var matchType models.MatchType
    37  	if metric == wildcard {
    38  		if count == 0 {
    39  			// Match field does not actually match all values
    40  			// for the first metric selector in practice.
    41  			// Need to special case this and just use a regexp match all
    42  			// on this first value.
    43  			// This is ok since there usually a very small amount of distinct
    44  			// values in the first dot separator.
    45  			return models.Matcher{
    46  				Type:  models.MatchRegexp,
    47  				Name:  graphite.TagName(count),
    48  				Value: []byte(".*"),
    49  			}, nil
    50  		}
    51  		return models.Matcher{
    52  			Type: models.MatchField,
    53  			Name: graphite.TagName(count),
    54  		}, nil
    55  	}
    56  
    57  	value, isRegex, err := graphite.GlobToRegexPattern(metric)
    58  	if err != nil {
    59  		return models.Matcher{}, err
    60  	}
    61  
    62  	if isRegex {
    63  		matchType = models.MatchRegexp
    64  	} else {
    65  		matchType = models.MatchEqual
    66  	}
    67  
    68  	return models.Matcher{
    69  		Type:  matchType,
    70  		Name:  graphite.TagName(count),
    71  		Value: value,
    72  	}, nil
    73  }
    74  
    75  func matcherTerminator(count int) models.Matcher {
    76  	return models.Matcher{
    77  		Type: models.MatchNotField,
    78  		Name: graphite.TagName(count),
    79  	}
    80  }