github.com/1aal/kubeblocks@v0.0.0-20231107070852-e1c03e598921/pkg/unstructured/lexer.go (about)

     1  /*
     2  Copyright (C) 2022-2023 ApeCloud Co., Ltd
     3  
     4  This file is part of KubeBlocks project
     5  
     6  This program is free software: you can redistribute it and/or modify
     7  it under the terms of the GNU Affero General Public License as published by
     8  the Free Software Foundation, either version 3 of the License, or
     9  (at your option) any later version.
    10  
    11  This program is distributed in the hope that it will be useful
    12  but WITHOUT ANY WARRANTY; without even the implied warranty of
    13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    14  GNU Affero General Public License for more details.
    15  
    16  You should have received a copy of the GNU Affero General Public License
    17  along with this program.  If not, see <http://www.gnu.org/licenses/>.
    18  */
    19  
    20  package unstructured
    21  
    22  import (
    23  	"bufio"
    24  	"reflect"
    25  	"sort"
    26  	"strings"
    27  )
    28  
    29  type Item struct {
    30  	LineNo   int
    31  	Comments []string
    32  	Values   []string
    33  }
    34  
    35  type Lexer struct {
    36  	lines []string
    37  	dict  map[string][]Item
    38  
    39  	isUpdated bool
    40  }
    41  
    42  const trimChars = " \r\n\t"
    43  
    44  func (i *Item) addToken(str string) {
    45  	if i.Values == nil {
    46  		i.Values = make([]string, 0)
    47  	}
    48  	i.Values = append(i.Values, str)
    49  }
    50  
    51  func (l *Lexer) getItem(key string) []Item {
    52  	return l.dict[key]
    53  }
    54  
    55  func (l *Lexer) parseParameter(paramLine string, paramID int) (Item, error) {
    56  	paramItem := Item{LineNo: paramID}
    57  	itemWrap := fsm{
    58  		param:           &paramItem,
    59  		splitCharacters: trimChars,
    60  	}
    61  	return paramItem, itemWrap.parse(paramLine)
    62  }
    63  
    64  func (l *Lexer) appendConfigLine(parameterLine string) {
    65  	l.lines = append(l.lines, parameterLine)
    66  }
    67  
    68  func (l *Lexer) appendValidParameter(param Item, fromNo int) {
    69  	newItem := param
    70  	key := newItem.Values[0]
    71  	l.addParameterComments(&newItem, fromNo+1, param.LineNo)
    72  	if _, ok := l.dict[key]; !ok {
    73  		l.dict[key] = make([]Item, 0)
    74  	}
    75  	l.dict[key] = append(l.dict[key], newItem)
    76  	l.isUpdated = true
    77  }
    78  
    79  func (l *Lexer) addParameterComments(param *Item, start, end int) {
    80  	if start+1 >= end {
    81  		return
    82  	}
    83  	param.Comments = l.lines[start:end]
    84  }
    85  
    86  func (l *Lexer) Load(str string) error {
    87  	var err error
    88  
    89  	param := Item{LineNo: -1}
    90  	scanner := bufio.NewScanner(strings.NewReader(str))
    91  	l.dict = make(map[string][]Item)
    92  	for scanner.Scan() {
    93  		parameterLine := strings.Trim(scanner.Text(), trimChars)
    94  		lineNo := len(l.lines)
    95  		l.appendConfigLine(parameterLine)
    96  		if parameterLine == "" || parameterLine[0] == '#' {
    97  			continue
    98  		}
    99  		lastScanNo := param.LineNo
   100  		if param, err = l.parseParameter(parameterLine, lineNo); err != nil {
   101  			return err
   102  		}
   103  		l.appendValidParameter(param, lastScanNo)
   104  	}
   105  
   106  	l.isUpdated = false
   107  	return nil
   108  }
   109  
   110  func (l *Lexer) removeParameter(it *Item) {
   111  	v, ok := l.dict[it.Values[0]]
   112  	if !ok {
   113  		return
   114  	}
   115  
   116  	index := -1
   117  	for i := range v {
   118  		if reflect.DeepEqual(&v[i], it) {
   119  			index = i
   120  			break
   121  		}
   122  	}
   123  
   124  	if index >= 0 {
   125  		l.dict[it.Values[0]] = append(v[:index], v[index+1:]...)
   126  	}
   127  	l.isUpdated = true
   128  }
   129  
   130  func (l *Lexer) sortParameters() []Item {
   131  	items := make([]Item, 0)
   132  	for _, v := range l.dict {
   133  		items = append(items, v...)
   134  	}
   135  	sort.SliceStable(items, func(i, j int) bool {
   136  		no1 := items[i].LineNo
   137  		no2 := items[j].LineNo
   138  		if no1 == no2 {
   139  			return strings.Compare(items[i].Values[0], items[j].Values[0]) < 0
   140  		}
   141  		return no1 < no2
   142  	})
   143  	return items
   144  }
   145  
   146  func (l *Lexer) empty() bool {
   147  	return len(l.dict) == 0
   148  }
   149  
   150  func (l *Lexer) getAllParams() map[string][]Item {
   151  	return l.dict
   152  }
   153  
   154  func (l *Lexer) toString() string {
   155  	return strings.Join(l.lines, "\n")
   156  }