github.com/XiaoMi/Gaea@v1.2.5/stats/kebab_case_converter.go (about)

     1  /*
     2  Copyright 2018 The Vitess Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package stats
    18  
    19  import (
    20  	"regexp"
    21  	"strings"
    22  	"sync"
    23  )
    24  
    25  // toKebabCase produces a monitoring compliant name from the
    26  // original. It converts CamelCase to camel-case,
    27  // and CAMEL_CASE to camel-case. For numbers, it
    28  // converts 0.5 to v0_5.
    29  func toKebabCase(name string) (hyphenated string) {
    30  	memoizer.Lock()
    31  	defer memoizer.Unlock()
    32  	if hyphenated = memoizer.memo[name]; hyphenated != "" {
    33  		return hyphenated
    34  	}
    35  	hyphenated = name
    36  	for _, converter := range kebabConverters {
    37  		hyphenated = converter.re.ReplaceAllString(hyphenated, converter.repl)
    38  	}
    39  	hyphenated = strings.ToLower(hyphenated)
    40  	memoizer.memo[name] = hyphenated
    41  	return
    42  }
    43  
    44  var kebabConverters = []struct {
    45  	re   *regexp.Regexp
    46  	repl string
    47  }{
    48  	// example: LC -> L-C (e.g. CamelCase -> Camel-Case).
    49  	{regexp.MustCompile("([a-z])([A-Z])"), "$1-$2"},
    50  	// example: CCa -> C-Ca (e.g. CCamel -> C-Camel).
    51  	{regexp.MustCompile("([A-Z])([A-Z][a-z])"), "$1-$2"},
    52  	{regexp.MustCompile("_"), "-"},
    53  	{regexp.MustCompile("\\."), "_"},
    54  }
    55  
    56  var memoizer = memoizerType{
    57  	memo: make(map[string]string),
    58  }
    59  
    60  type memoizerType struct {
    61  	sync.Mutex
    62  	memo map[string]string
    63  }