github.com/sdbaiguanghe/helm@v2.16.7+incompatible/cmd/helm/search/search.go (about) 1 /* 2 Copyright The Helm 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 search provides client-side repository searching. 18 19 This supports building an in-memory search index based on the contents of 20 multiple repositories, and then using string matching or regular expressions 21 to find matches. 22 */ 23 package search 24 25 import ( 26 "errors" 27 "path" 28 "regexp" 29 "sort" 30 "strings" 31 32 "github.com/Masterminds/semver" 33 "k8s.io/helm/pkg/repo" 34 ) 35 36 const ( 37 sep = "\v" 38 // verSep is a separator for version fields in map keys. 39 verSep = "$$" 40 ) 41 42 // Result is a search result. 43 // 44 // Score indicates how close it is to match. The higher the score, the longer 45 // the distance. 46 type Result struct { 47 Name string 48 Score int 49 Chart *repo.ChartVersion 50 } 51 52 // Index is a searchable index of chart information. 53 type Index struct { 54 lines map[string]string 55 charts map[string]*repo.ChartVersion 56 } 57 58 // NewIndex creates a new Index. 59 func NewIndex() *Index { 60 return &Index{lines: map[string]string{}, charts: map[string]*repo.ChartVersion{}} 61 } 62 63 // AddRepo adds a repository index to the search index. 64 func (i *Index) AddRepo(rname string, ind *repo.IndexFile, all bool) { 65 ind.SortEntries() 66 for name, ref := range ind.Entries { 67 if len(ref) == 0 { 68 // Skip chart names that have zero releases. 69 continue 70 } 71 // By convention, an index file is supposed to have the newest at the 72 // 0 slot, so our best bet is to grab the 0 entry and build the index 73 // entry off of that. 74 // Note: Do not use filePath.Join since on Windows it will return \ 75 // which results in a repo name that cannot be understood. 76 fname := path.Join(rname, name) 77 if !all { 78 i.lines[fname] = indstr(rname, ref[0]) 79 i.charts[fname] = ref[0] 80 continue 81 } 82 83 // If 'all' is set, then we go through all of the refs, and add them all 84 // to the index. This will generate a lot of near-duplicate entries. 85 for _, rr := range ref { 86 versionedName := fname + verSep + rr.Version 87 i.lines[versionedName] = indstr(rname, rr) 88 i.charts[versionedName] = rr 89 } 90 } 91 } 92 93 // All returns all charts in the index as if they were search results. 94 // 95 // Each will be given a score of 0. 96 func (i *Index) All() []*Result { 97 res := make([]*Result, len(i.charts)) 98 j := 0 99 for name, ch := range i.charts { 100 parts := strings.Split(name, verSep) 101 res[j] = &Result{ 102 Name: parts[0], 103 Chart: ch, 104 } 105 j++ 106 } 107 return res 108 } 109 110 // Search searches an index for the given term. 111 // 112 // Threshold indicates the maximum score a term may have before being marked 113 // irrelevant. (Low score means higher relevance. Golf, not bowling.) 114 // 115 // If regexp is true, the term is treated as a regular expression. Otherwise, 116 // term is treated as a literal string. 117 func (i *Index) Search(term string, threshold int, regexp bool) ([]*Result, error) { 118 if regexp { 119 return i.SearchRegexp(term, threshold) 120 } 121 return i.SearchLiteral(term, threshold), nil 122 } 123 124 // calcScore calculates a score for a match. 125 func (i *Index) calcScore(index int, matchline string) int { 126 127 // This is currently tied to the fact that sep is a single char. 128 splits := []int{} 129 s := rune(sep[0]) 130 for i, ch := range matchline { 131 if ch == s { 132 splits = append(splits, i) 133 } 134 } 135 136 for i, pos := range splits { 137 if index > pos { 138 continue 139 } 140 return i 141 } 142 return len(splits) 143 } 144 145 // SearchLiteral does a literal string search (no regexp). 146 func (i *Index) SearchLiteral(term string, threshold int) []*Result { 147 term = strings.ToLower(term) 148 buf := []*Result{} 149 for k, v := range i.lines { 150 lk := strings.ToLower(k) 151 lv := strings.ToLower(v) 152 res := strings.Index(lv, term) 153 if score := i.calcScore(res, lv); res != -1 && score < threshold { 154 parts := strings.Split(lk, verSep) // Remove version, if it is there. 155 buf = append(buf, &Result{Name: parts[0], Score: score, Chart: i.charts[k]}) 156 } 157 } 158 return buf 159 } 160 161 // SearchRegexp searches using a regular expression. 162 func (i *Index) SearchRegexp(re string, threshold int) ([]*Result, error) { 163 matcher, err := regexp.Compile(re) 164 if err != nil { 165 return []*Result{}, err 166 } 167 buf := []*Result{} 168 for k, v := range i.lines { 169 ind := matcher.FindStringIndex(v) 170 if len(ind) == 0 { 171 continue 172 } 173 if score := i.calcScore(ind[0], v); ind[0] >= 0 && score < threshold { 174 parts := strings.Split(k, verSep) // Remove version, if it is there. 175 buf = append(buf, &Result{Name: parts[0], Score: score, Chart: i.charts[k]}) 176 } 177 } 178 return buf, nil 179 } 180 181 // Chart returns the ChartVersion for a particular name. 182 func (i *Index) Chart(name string) (*repo.ChartVersion, error) { 183 c, ok := i.charts[name] 184 if !ok { 185 return nil, errors.New("no such chart") 186 } 187 return c, nil 188 } 189 190 // SortScore does an in-place sort of the results. 191 // 192 // Lowest scores are highest on the list. Matching scores are subsorted alphabetically. 193 func SortScore(r []*Result) { 194 sort.Sort(scoreSorter(r)) 195 } 196 197 // scoreSorter sorts results by score, and subsorts by alpha Name. 198 type scoreSorter []*Result 199 200 // Len returns the length of this scoreSorter. 201 func (s scoreSorter) Len() int { return len(s) } 202 203 // Swap performs an in-place swap. 204 func (s scoreSorter) Swap(i, j int) { s[i], s[j] = s[j], s[i] } 205 206 // Less compares a to b, and returns true if a is less than b. 207 func (s scoreSorter) Less(a, b int) bool { 208 first := s[a] 209 second := s[b] 210 211 if first.Score > second.Score { 212 return false 213 } 214 if first.Score < second.Score { 215 return true 216 } 217 if first.Name == second.Name { 218 v1, err := semver.NewVersion(first.Chart.Version) 219 if err != nil { 220 return true 221 } 222 v2, err := semver.NewVersion(second.Chart.Version) 223 if err != nil { 224 return true 225 } 226 // Sort so that the newest chart is higher than the oldest chart. This is 227 // the opposite of what you'd expect in a function called Less. 228 return v1.GreaterThan(v2) 229 } 230 return first.Name < second.Name 231 } 232 233 func indstr(name string, ref *repo.ChartVersion) string { 234 i := ref.Name + sep + name + "/" + ref.Name + sep + 235 ref.Description + sep + strings.Join(ref.Keywords, " ") 236 return i 237 }