doc

@xen-orchestra/fs/src/abstract.js

@@ -91,6 +91,7 @@ export default class RemoteHandlerAbstract {
     const sharedLimit = limitConcurrency(options.maxParallelOperations ?? DEFAULT_MAX_PARALLEL_OPERATIONS)
     this.closeFile = sharedLimit(this.closeFile)
     this.copy = sharedLimit(this.copy)
+    this.exists = sharedLimit(this.exists)
     this.getInfo = sharedLimit(this.getInfo)
     this.getSize = sharedLimit(this.getSize)
     this.list = sharedLimit(this.list)
@@ -314,6 +315,14 @@ export default class RemoteHandlerAbstract {
     await this._rmtree(normalizePath(dir))
   }
 
+  async _exists(file){
+    throw new Error('not implemented')
+  }
+  async exists(file){
+    return this._exists(normalizePath(file))
+
+  }
+
   // Asks the handler to sync the state of the effective remote with its'
   // metadata
   //

@xen-orchestra/fs/src/local.js

@@ -198,4 +198,9 @@ export default class LocalHandler extends RemoteHandlerAbstract {
   _writeFile(file, data, { flags }) {
     return this._addSyncStackTrace(fs.writeFile, this._getFilePath(file), data, { flag: flags })
   }
+
+  async _exists(file){
+    const exists = await  fs.pathExists(this._getFilePath(file))
+    return exists
+  }
 }

@xen-orchestra/fs/src/s3.js

@@ -537,4 +537,17 @@ export default class S3Handler extends RemoteHandlerAbstract {
   useVhdDirectory() {
     return true
   }
+
+  async _exists(file){
+    try{
+      await this._s3.send(new HeadObjectCommand(this._createParams(file)))
+      return true
+    }catch(error){
+      // normalize this error code
+      if (error.name === 'NoSuchKey') {
+        return false
+      }
+      throw error
+    }
+  }
 }

CHANGELOG.unreleased.md

@@ -30,7 +30,8 @@
 > Keep this list alphabetically ordered to avoid merge conflicts
 
 <!--packages-start-->
-
+- vhd-lib minor
+- vhd-cli major
 - @xen-orchestra/backups-cli major
 - @xen-orchestra/log minor
 - xo-cli patch

packages/vhd-cli/.USAGE.md

@@ -0,0 +1,44 @@
+```
+> vhd-cli
+Usage:
+
+    vhd-cli check <path>
+
+      Detects issues with VHD. path is relative to the remote url
+
+      Options:
+        --remote <url>  the remote url, / if not specified
+        --bat           check if the blocks listed in the bat are present on the file system (vhddirectory only)
+        --blocks        read all the blocks of the vhd
+        --chain         instantiate a vhd with all its parent and check it
+
+    vhd-cli compare <sourceRemoteUrl> <source VHD> <destionationRemoteUrl> <destination>
+
+      Check if two VHD contains the same data
+
+
+    vhd-cli copy <sourceRemoteUrl> <source VHD> <destionationRemoteUrl> <destination> --directory
+
+      Copy a Vhd.
+
+      Options:
+        --directory : the destination vhd will be created as a vhd directory
+
+    vhd-cli info <path>
+
+      Read informations of a VHD, path is relative to /
+
+    vhd-cli merge <child VHD> <parent VHD>
+
+      Merge child in parent, paths are relatives to /
+
+    vhd-cli raw <path>
+
+      extract the raw content of a VHD, path is relative to /
+
+    vhd-cli repl
+
+      create a REPL environnement in the local folder
+
+
+```

packages/vhd-cli/commands/check.js

@@ -1,30 +1,51 @@
 'use strict'
 
-const { VhdFile, checkVhdChain } = require('vhd-lib')
+const { openVhd, VhdSynthetic } = require('vhd-lib')
 const getopts = require('getopts')
 const { getSyncedHandler } = require('@xen-orchestra/fs')
-const { resolve } = require('path')
 const { Disposable } = require('promise-toolbox')
 
-const checkVhd = (handler, path) => new VhdFile(handler, path).readHeaderAndFooter()
-
 module.exports = async function check(rawArgs) {
-  const { chain, _: args } = getopts(rawArgs, {
-    boolean: ['chain'],
+
+  if (args.length < 2 || args.some(_ => _ === '-h' || _ === '--help')) {
+    return `Usage: ${this.command} <path> [--remote <remoteURL>] [--chain] [--bat] [--blocks] `
+  }
+  const { chain, bat, blocks, remote, _: args } = getopts(rawArgs, {
+    boolean: ['chain', 'bat', 'blocks'],
     default: {
       chain: false,
+      bat: false,
+      blocks: false
     },
   })
 
-  const check = chain ? checkVhdChain : checkVhd
-  await Disposable.use(getSyncedHandler({ url: 'file:///' }), async handler => {
-    for (const vhd of args) {
-      try {
-        await check(handler, resolve(vhd))
-        console.log('ok:', vhd)
-      } catch (error) {
-        console.error('nok:', vhd, error)
+  const vhdPath = args[0]
+
+  await Disposable.factory( async function * open(remote, vhdPath) {
+    const handler = yield getSyncedHandler({url : remote ?? 'file:///'})
+    const vhd = chain? yield VhdSynthetic.fromVhdChain(handler, vhdPath) : yield openVhd(handler, vhdPath)
+
+    await vhd.readBlockAllocationTable()
+    if(bat){
+      const nBlocks = vhd.header.maxTableEntries
+      let nbErrors = 0
+      for (let blockId = 0; blockId < nBlocks; ++blockId) {
+        if(!vhd.containsBlock(blockId)){
+         continue
+        }
+        const ok = await vhd.checkBlock(blockId)
+        if(!ok){
+          console.warn(`block ${blockId} is invalid`)
+          nbErrors ++
+        }
       }
+      console.log('BAT check done ', nbErrors === 0  ? 'OK':  `${nbErrors} block(s) faileds`)
     }
-  })
+    if(blocks){
+      for await(const _ of vhd.blocks()){
+
+      }
+      console.log('Blocks check done')
+    }
+  })(remote, vhdPath)
 }

packages/vhd-lib/Vhd/VhdAbstract.js

@@ -394,4 +394,14 @@ exports.VhdAbstract = class VhdAbstract {
     assert.strictEqual(copied, length, 'invalid length')
     return copied
   }
+
+  _checkBlock() {
+    throw new Error('not implemented')
+  }
+
+  // check if a block is ok without reading it
+  // there still can be error when reading the block later (if it's deleted, if right are incorrects,...)
+  async checkBlock(blockId) {
+    return this._checkBlock(blockId)
+  }
 }

packages/vhd-lib/Vhd/VhdDirectory.js

@@ -317,4 +317,9 @@ exports.VhdDirectory = class VhdDirectory extends VhdAbstract {
     })
     this.#compressor = getCompressor(chunkFilters[0])
   }
+
+  async _checkBlock(blockId){
+    const path = this._getFullBlockPath(blockId)
+    return this._handler.exists(path)
+  }
 }

packages/vhd-lib/Vhd/VhdFile.js

@@ -466,4 +466,8 @@ exports.VhdFile = class VhdFile extends VhdAbstract {
   async getSize() {
     return await this._handler.getSize(this._path)
   }
+
+  _checkBlock(blockId){
+    return true
+  }
 }

packages/vhd-lib/Vhd/VhdSynthetic.js

@@ -113,6 +113,10 @@ const VhdSynthetic = class VhdSynthetic extends VhdAbstract {
     return vhd?._getFullBlockPath(blockId)
   }
 
+  _checkBlock(blockId) {
+    const vhd = this.#getVhdWithBlock(blockId)
+    return vhd?._checkBlock(blockId) ?? false
+  }
   // return true if all the vhds ar an instance of cls
   checkVhdsClass(cls) {
     return this.#vhds.every(vhd => vhd instanceof cls)