| 1 | import { type FSWatcher, readFileSync } from 'node:fs' |
| 2 | |
| 3 | import type { ChargingStation } from './ChargingStation.js' |
| 4 | import { getIdTagsFile } from './Helpers.js' |
| 5 | import { FileType, IdTagDistribution } from '../types/index.js' |
| 6 | import { |
| 7 | handleFileException, |
| 8 | isNotEmptyString, |
| 9 | logPrefix, |
| 10 | logger, |
| 11 | secureRandom, |
| 12 | watchJsonFile |
| 13 | } from '../utils/index.js' |
| 14 | |
| 15 | interface IdTagsCacheValueType { |
| 16 | idTags: string[] |
| 17 | idTagsFileWatcher: FSWatcher | undefined |
| 18 | } |
| 19 | |
| 20 | export class IdTagsCache { |
| 21 | private static instance: IdTagsCache | null = null |
| 22 | private readonly idTagsCaches: Map<string, IdTagsCacheValueType> |
| 23 | private readonly idTagsCachesAddressableIndexes: Map<string, number> |
| 24 | |
| 25 | private constructor () { |
| 26 | this.idTagsCaches = new Map<string, IdTagsCacheValueType>() |
| 27 | this.idTagsCachesAddressableIndexes = new Map<string, number>() |
| 28 | } |
| 29 | |
| 30 | public static getInstance (): IdTagsCache { |
| 31 | if (IdTagsCache.instance === null) { |
| 32 | IdTagsCache.instance = new IdTagsCache() |
| 33 | } |
| 34 | return IdTagsCache.instance |
| 35 | } |
| 36 | |
| 37 | /** |
| 38 | * Gets one idtag from the cache given the distribution |
| 39 | * Must be called after checking the cache is not an empty array |
| 40 | * |
| 41 | * @param distribution - |
| 42 | * @param chargingStation - |
| 43 | * @param connectorId - |
| 44 | * @returns |
| 45 | */ |
| 46 | public getIdTag ( |
| 47 | distribution: IdTagDistribution, |
| 48 | chargingStation: ChargingStation, |
| 49 | connectorId: number |
| 50 | ): string { |
| 51 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 52 | const hashId = chargingStation.stationInfo!.hashId |
| 53 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 54 | const idTagsFile = getIdTagsFile(chargingStation.stationInfo!)! |
| 55 | switch (distribution) { |
| 56 | case IdTagDistribution.RANDOM: |
| 57 | return this.getRandomIdTag(hashId, idTagsFile) |
| 58 | case IdTagDistribution.ROUND_ROBIN: |
| 59 | return this.getRoundRobinIdTag(hashId, idTagsFile) |
| 60 | case IdTagDistribution.CONNECTOR_AFFINITY: |
| 61 | return this.getConnectorAffinityIdTag(chargingStation, connectorId) |
| 62 | default: |
| 63 | return this.getRoundRobinIdTag(hashId, idTagsFile) |
| 64 | } |
| 65 | } |
| 66 | |
| 67 | /** |
| 68 | * Gets all idtags from the cache |
| 69 | * Must be called after checking the cache is not an empty array |
| 70 | * |
| 71 | * @param file - |
| 72 | * @returns |
| 73 | */ |
| 74 | public getIdTags (file: string): string[] | undefined { |
| 75 | if (!this.hasIdTagsCache(file)) { |
| 76 | this.setIdTagsCache(file, this.getIdTagsFromFile(file)) |
| 77 | } |
| 78 | return this.getIdTagsCache(file) |
| 79 | } |
| 80 | |
| 81 | public deleteIdTags (file: string): boolean { |
| 82 | return this.deleteIdTagsCache(file) && this.deleteIdTagsCacheIndexes(file) |
| 83 | } |
| 84 | |
| 85 | private getRandomIdTag (hashId: string, file: string): string { |
| 86 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 87 | const idTags = this.getIdTags(file)! |
| 88 | const addressableKey = this.getIdTagsCacheIndexesAddressableKey(file, hashId) |
| 89 | this.idTagsCachesAddressableIndexes.set( |
| 90 | addressableKey, |
| 91 | Math.floor(secureRandom() * idTags.length) |
| 92 | ) |
| 93 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 94 | return idTags[this.idTagsCachesAddressableIndexes.get(addressableKey)!] |
| 95 | } |
| 96 | |
| 97 | private getRoundRobinIdTag (hashId: string, file: string): string { |
| 98 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 99 | const idTags = this.getIdTags(file)! |
| 100 | const addressableKey = this.getIdTagsCacheIndexesAddressableKey(file, hashId) |
| 101 | const idTagIndex = this.idTagsCachesAddressableIndexes.get(addressableKey) ?? 0 |
| 102 | const idTag = idTags[idTagIndex] |
| 103 | this.idTagsCachesAddressableIndexes.set( |
| 104 | addressableKey, |
| 105 | idTagIndex === idTags.length - 1 ? 0 : idTagIndex + 1 |
| 106 | ) |
| 107 | return idTag |
| 108 | } |
| 109 | |
| 110 | private getConnectorAffinityIdTag (chargingStation: ChargingStation, connectorId: number): string { |
| 111 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 112 | const file = getIdTagsFile(chargingStation.stationInfo!)! |
| 113 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 114 | const idTags = this.getIdTags(file)! |
| 115 | const addressableKey = this.getIdTagsCacheIndexesAddressableKey( |
| 116 | file, |
| 117 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 118 | chargingStation.stationInfo!.hashId |
| 119 | ) |
| 120 | this.idTagsCachesAddressableIndexes.set( |
| 121 | addressableKey, |
| 122 | (chargingStation.index - 1 + (connectorId - 1)) % idTags.length |
| 123 | ) |
| 124 | // eslint-disable-next-line @typescript-eslint/no-non-null-assertion |
| 125 | return idTags[this.idTagsCachesAddressableIndexes.get(addressableKey)!] |
| 126 | } |
| 127 | |
| 128 | private hasIdTagsCache (file: string): boolean { |
| 129 | return this.idTagsCaches.has(file) |
| 130 | } |
| 131 | |
| 132 | private setIdTagsCache (file: string, idTags: string[]): Map<string, IdTagsCacheValueType> { |
| 133 | return this.idTagsCaches.set(file, { |
| 134 | idTags, |
| 135 | idTagsFileWatcher: watchJsonFile( |
| 136 | file, |
| 137 | FileType.Authorization, |
| 138 | this.logPrefix(file), |
| 139 | undefined, |
| 140 | (event, filename) => { |
| 141 | if (isNotEmptyString(filename) && event === 'change') { |
| 142 | try { |
| 143 | logger.debug( |
| 144 | `${this.logPrefix(file)} ${FileType.Authorization} file have changed, reload` |
| 145 | ) |
| 146 | this.deleteIdTagsCache(file) |
| 147 | this.deleteIdTagsCacheIndexes(file) |
| 148 | } catch (error) { |
| 149 | handleFileException( |
| 150 | file, |
| 151 | FileType.Authorization, |
| 152 | error as NodeJS.ErrnoException, |
| 153 | this.logPrefix(file), |
| 154 | { |
| 155 | throwError: false |
| 156 | } |
| 157 | ) |
| 158 | } |
| 159 | } |
| 160 | } |
| 161 | ) |
| 162 | }) |
| 163 | } |
| 164 | |
| 165 | private getIdTagsCache (file: string): string[] | undefined { |
| 166 | return this.idTagsCaches.get(file)?.idTags |
| 167 | } |
| 168 | |
| 169 | private deleteIdTagsCache (file: string): boolean { |
| 170 | this.idTagsCaches.get(file)?.idTagsFileWatcher?.close() |
| 171 | return this.idTagsCaches.delete(file) |
| 172 | } |
| 173 | |
| 174 | private deleteIdTagsCacheIndexes (file: string): boolean { |
| 175 | const deleted: boolean[] = [] |
| 176 | for (const [key] of this.idTagsCachesAddressableIndexes) { |
| 177 | if (key.startsWith(file)) { |
| 178 | deleted.push(this.idTagsCachesAddressableIndexes.delete(key)) |
| 179 | } |
| 180 | } |
| 181 | return !deleted.some((value) => !value) |
| 182 | } |
| 183 | |
| 184 | private getIdTagsCacheIndexesAddressableKey (prefix: string, uid: string): string { |
| 185 | return `${prefix}${uid}` |
| 186 | } |
| 187 | |
| 188 | private getIdTagsFromFile (file: string): string[] { |
| 189 | if (isNotEmptyString(file)) { |
| 190 | try { |
| 191 | return JSON.parse(readFileSync(file, 'utf8')) as string[] |
| 192 | } catch (error) { |
| 193 | handleFileException( |
| 194 | file, |
| 195 | FileType.Authorization, |
| 196 | error as NodeJS.ErrnoException, |
| 197 | this.logPrefix(file) |
| 198 | ) |
| 199 | } |
| 200 | } |
| 201 | return [] |
| 202 | } |
| 203 | |
| 204 | private readonly logPrefix = (file: string): string => { |
| 205 | return logPrefix(` Id tags cache for id tags file '${file}' |`) |
| 206 | } |
| 207 | } |