server/helpers/decache.ts

   1 // Thanks: https://github.com/dwyl/decache
   2 // We reuse this file to also uncache plugin base path
   3
   4 import { extname } from 'path'
   5
   6 function decachePlugin (pluginPath: string, libraryPath: string) {
   7   const moduleName = find(libraryPath)
   8
   9   if (!moduleName) return
  10
  11   searchCache(moduleName, function (mod) {
  12     delete require.cache[mod.id]
  13   })
  14
  15   removeCachedPath(pluginPath)
  16 }
  17
  18 function decacheModule (name: string) {
  19   const moduleName = find(name)
  20
  21   if (!moduleName) return
  22
  23   searchCache(moduleName, function (mod) {
  24     delete require.cache[mod.id]
  25   })
  26
  27   removeCachedPath(moduleName)
  28 }
  29
  30 // ---------------------------------------------------------------------------
  31
  32 export {
  33   decacheModule,
  34   decachePlugin
  35 }
  36
  37 // ---------------------------------------------------------------------------
  38
  39 function find (moduleName: string) {
  40   try {
  41     return require.resolve(moduleName)
  42   } catch {
  43     return ''
  44   }
  45 }
  46
  47 function searchCache (moduleName: string, callback: (current: NodeModule) => void) {
  48   const resolvedModule = require.resolve(moduleName)
  49   let mod: NodeModule
  50   const visited = {}
  51
  52   if (resolvedModule && ((mod = require.cache[resolvedModule]) !== undefined)) {
  53     // Recursively go over the results
  54     (function run (current) {
  55       visited[current.id] = true
  56
  57       current.children.forEach(function (child) {
  58         if (extname(child.filename) !== '.node' && !visited[child.id]) {
  59           run(child)
  60         }
  61       })
  62
  63       // Call the specified callback providing the
  64       // found module
  65       callback(current)
  66     })(mod)
  67   }
  68 };
  69
  70 function removeCachedPath (pluginPath: string) {
  71   const pathCache = (module.constructor as any)._pathCache as { [ id: string ]: string[] }
  72
  73   Object.keys(pathCache).forEach(function (cacheKey) {
  74     if (cacheKey.includes(pluginPath)) {
  75       delete pathCache[cacheKey]
  76     }
  77   })
  78 }