fix: rework optionnal depency

@vates/fuse-vhd/index.js

@@ -1,12 +1,8 @@
 'use strict'
 
 const LRU = require('lru-cache')
-const Fuse = require('fuse-native')
 const { VhdSynthetic } = require('vhd-lib')
 const { Disposable, fromCallback } = require('promise-toolbox')
-const { createLogger } = require('@xen-orchestra/log')
-
-const { warn } = createLogger('vates:fuse-vhd')
 
 // build a s stat object from https://github.com/fuse-friends/fuse-native/blob/master/test/fixtures/stat.js
 const stat = st => ({
@@ -20,6 +16,7 @@ const stat = st => ({
 })
 
 exports.mount = Disposable.factory(async function* mount(handler, diskPath, mountDir) {
+  const Fuse = require('fuse-native')
   const vhd = yield VhdSynthetic.fromVhdChain(handler, diskPath)
 
   const cache = new LRU({
@@ -57,9 +54,7 @@ exports.mount = Disposable.factory(async function* mount(handler, diskPath, moun
     },
     read(path, fd, buf, len, pos, cb) {
       if (path === '/vhd0') {
-        return vhd
+        return vhd.readRawData(pos, len, cache, buf).then(cb)
-          .readRawData(pos, len, cache, buf)
-          .then(cb)
       }
       throw new Error(`read file ${path} not exists`)
     },
@@ -67,5 +62,5 @@ exports.mount = Disposable.factory(async function* mount(handler, diskPath, moun
   return new Disposable(
     () => fromCallback(() => fuse.unmount()),
     fromCallback(() => fuse.mount())
-    )
+  )
 })

@vates/fuse-vhd/package.json

@@ -19,11 +19,13 @@
   },
   "dependencies": {
     "@xen-orchestra/log": "^0.3.0",
-    "fuse-native": "^2.2.6",
     "lru-cache": "^7.14.0",
     "promise-toolbox": "^0.21.0",
     "vhd-lib": "^4.0.1"
   },
+  "optionalDependencies": {
+    "fuse-native": "^2.2.6"
+  },
   "scripts": {
     "postversion": "npm publish --access public"
   }

@xen-orchestra/backups/RemoteAdapter.js

@@ -28,10 +28,8 @@ const { isMetadataFile } = require('./_backupType.js')
 const { isValidXva } = require('./_isValidXva.js')
 const { listPartitions, LVM_PARTITION_TYPE } = require('./_listPartitions.js')
 const { lvs, pvs } = require('./_lvm.js')
-// @todo : this import is marked extraneous , sould be fixed when lib is published
-const { mount } = require('@vates/fuse-vhd')
 const { asyncEach } = require('@vates/async-each')
-
+const { mount } = require('@vates/fuse-vhd')
 const DIR_XO_CONFIG_BACKUPS = 'xo-config-backups'
 exports.DIR_XO_CONFIG_BACKUPS = DIR_XO_CONFIG_BACKUPS
 
@@ -76,14 +74,16 @@ const debounceResourceFactory = factory =>
   }
 
 class RemoteAdapter {
-  constructor(handler, { debounceResource = res => res, dirMode, vhdDirectoryCompression, useGetDiskLegacy=false } = {}) {
+  constructor(
+    handler,
+    { debounceResource = res => res, dirMode, vhdDirectoryCompression, useGetDiskLegacy = false } = {}
+  ) {
     this._debounceResource = debounceResource
     this._dirMode = dirMode
     this._handler = handler
     this._vhdDirectoryCompression = vhdDirectoryCompression
     this._readCacheListVmBackups = synchronized.withKey()(this._readCacheListVmBackups)
     this._useGetDiskLegacy = useGetDiskLegacy
-
   }
 
   get handler() {
@@ -324,9 +324,7 @@ class RemoteAdapter {
     return this.#useVhdDirectory()
   }
 
-
   async *#getDiskLegacy(diskId) {
-
     const RE_VHDI = /^vhdi(\d+)$/
     const handler = this._handler
 
@@ -358,15 +356,25 @@ class RemoteAdapter {
   }
 
   async *getDisk(diskId) {
-    if(this._useGetDiskLegacy){
+    if (this._useGetDiskLegacy) {
-      yield * this.#getDiskLegacy(diskId)
+      yield* this.#getDiskLegacy(diskId)
       return
     }
     const handler = this._handler
     // this is a disposable
     const mountDir = yield getTmpDir()
-    // this is also a disposable
+
-    yield mount(handler, diskId, mountDir)
+    try {
+      // this is also a disposable
+      yield mount(handler, diskId, mountDir)
+    } catch (error) {
+      // fallback in case of missing dependency
+      if (error.code === 'MODULE_NOT_FOUND') {
+        yield* this.#getDiskLegacy(diskId)
+      } else {
+        throw error
+      }
+    }
     // this will yield disk path to caller
     yield `${mountDir}/vhd0`
   }