Some corrections for delta integration in xo-web.

- List delta backups in subfolders.
- Fix unhandled exception. (ENOENT)
- ...

src/api/vbd.coffee

@@ -26,11 +26,8 @@ exports.delete = delete_
 
 disconnect = $coroutine ({vbd}) ->
   xapi = @getXAPI vbd
-
+  yield xapi.disconnectVBD(vbd._xapiRef)
-  # TODO: check if VBD is attached before
+  return
-  yield xapi.call 'VBD.unplug_force', vbd._xapiRef
-
-  return true
 
 disconnect.params = {
   id: { type: 'string' }
@@ -46,11 +43,8 @@ exports.disconnect = disconnect
 
 connect = $coroutine ({vbd}) ->
   xapi = @getXAPI vbd
-
+  yield xapi.connectVBD(vbd._xapiRef)
-  # TODO: check if VBD is attached before
+  return
-  yield xapi.call 'VBD.plug', vbd._xapiRef
-
-  return true
 
 connect.params = {
   id: { type: 'string' }

src/xapi.js

@@ -1026,7 +1026,7 @@ export default class Xapi extends XapiBase {
 
     let host
     let snapshotRef
-    if (isVmRunning(vm)) {
+    if (isVmRunning(vm) && !onlyMetadata) {
       host = vm.$resident_on
       snapshotRef = await this._snapshotVm(vm)
     } else {
@@ -1514,9 +1514,21 @@ export default class Xapi extends XapiBase {
     )
   }
 
+  async connectVBD (vbdId) {
+    await this.call('VBD.plug', vbdId)
+  }
+
+  async disconnectVBD (vbdId) {
+    // TODO: check if VBD is attached before
+    await this.call('VBD.unplug_force', vbdId)
+  }
+
   async destroyVbdsFromVm (vmId) {
     await Promise.all(
-      mapToArray(this.getObject(vmId).$VBDs, vbd => this.call('VBD.destroy', vbd.$ref))
+      mapToArray(this.getObject(vmId).$VBDs, async vbd => {
+        await this.disconnectVBD(vbd.$ref).catch(noop)
+        return this.call('VBD.destroy', vbd.$ref)
+      })
     )
   }
 

src/xo.js

@@ -766,14 +766,35 @@ export default class Xo extends EventEmitter {
     return this._listRemote(remote)
   }
 
+  async _listRemoteBackups (remote) {
+    const path = remote.path
+
+    // List backups. (Except delta backups)
+    const xvaFilter = file => endsWith(file, '.xva')
+
+    const files = await fs.readdir(path)
+    const backups = filter(files, xvaFilter)
+
+    // List delta backups.
+    const deltaDirs = filter(files, file => startsWith(file, 'vm_delta_'))
+
+    for (const deltaDir of deltaDirs) {
+      const files = await fs.readdir(`${path}/${deltaDir}`)
+      const deltaBackups = filter(files, xvaFilter)
+
+      Array.prototype.push.apply(backups, mapToArray(deltaBackups, deltaBackup => `${deltaDir}/${deltaBackup}`))
+    }
+
+    return backups
+  }
+
   async _listRemote (remote) {
     const fsRemotes = {
       nfs: true,
       local: true
     }
     if (remote.type in fsRemotes) {
-      const files = await fs.readdir(remote.path)
+      return this._listRemoteBackups(remote)
-      return filter(files, file => endsWith(file, '.xva'))
     }
     throw new Error('Unhandled remote type')
   }
@@ -827,24 +848,32 @@ export default class Xo extends EventEmitter {
     }
   }
 
-  async importVmBackup (remoteId, file, sr) {
+  async _openAndwaitReadableFile (path, errorMessage) {
-    const remote = await this.getRemote(remoteId)
-    const path = `${remote.path}/${file}`
     const stream = fs.createReadStream(path)
 
     try {
       await eventToPromise(stream, 'readable')
     } catch (error) {
       if (error.code === 'ENOENT') {
-        throw new Error('VM to import not found in this remote')
+        throw new Error(errorMessage)
       }
       throw error
     }
 
-    const xapi = this.getXAPI(sr)
     const stats = await fs.stat(path)
 
-    await xapi.importVm(stream, stats.size, { srId: sr._xapiId })
+    return [ stream, stats.size ]
+  }
+
+  async importVmBackup (remoteId, file, sr) {
+    const remote = await this.getRemote(remoteId)
+    const path = `${remote.path}/${file}`
+    const [ stream, length ] = await this._openAndwaitReadableFile(
+      path, 'VM to import not found in this remote')
+
+    const xapi = this.getXAPI(sr)
+
+    await xapi.importVm(stream, length, { srId: sr._xapiId })
   }
 
   // -----------------------------------------------------------------
@@ -900,39 +929,42 @@ export default class Xo extends EventEmitter {
 
     // Count delta backups.
     const nDelta = this._countDeltaVdiBackups(backups)
-    const isFull = (nDelta + 1 >= depth || !backups.length)
 
     // Make snapshot.
     const date = safeDateFormat(new Date())
-    const base = find(vdi.$snapshots, { name_label: 'BASE_VDI_SNAPSHOT' })
+    const base = find(vdi.$snapshots, { name_label: 'XO_DELTA_BASE_VDI_SNAPSHOT' })
-    const currentSnapshot = await xapi.snapshotVdi(vdi.$id, 'BASE_VDI_SNAPSHOT')
+    const currentSnapshot = await xapi.snapshotVdi(vdi.$id, 'XO_DELTA_BASE_VDI_SNAPSHOT')
+
+    // It is strange to have no base but a full backup !
+    // A full is necessary if it not exists backups or
+    // the number of delta backups is sufficient.
+    const isFull = (nDelta + 1 >= depth || !backups.length || !base)
 
     // Export full or delta backup.
     const vdiFilename = `${date}_${isFull ? 'full' : 'delta'}.vhd`
     const backupFullPath = `${path}/${vdiFilename}`
-    const sourceStream = await xapi.exportVdi(currentSnapshot.$id, {
-      baseId: isFull ? undefined : base.$id,
-      format: Xapi.VDI_FORMAT_VHD
-    })
 
     try {
-      await eventToPromise(
+      const sourceStream = await xapi.exportVdi(currentSnapshot.$id, {
-        sourceStream.pipe(
+        baseId: isFull ? undefined : base.$id,
-          fs.createWriteStream(backupFullPath, { flags: 'wx' })
+        format: Xapi.VDI_FORMAT_VHD
-        ),
+      })
-        'finish'
+
-      )
+      const targetStream = fs.createWriteStream(backupFullPath, { flags: 'wx' })
+      sourceStream.on('error', () => targetStream.emit('error'))
+      await eventToPromise(sourceStream.pipe(targetStream), 'finish')
     } catch (e) {
       // Remove backup. (corrupt)
+      await xapi.deleteVdi(currentSnapshot.$id)
       fs.unlink(backupFullPath).catch(noop)
       throw e
     }
 
-    // Remove last snapshot from last retention or previous snapshot.
     if (base) {
       await xapi.deleteVdi(base.$id)
     }
 
+    // Remove last snapshot from last retention or previous snapshot.
     backups.push(vdiFilename)
     await this._removeOldVdiBackups(backups, path, depth)
 
@@ -941,11 +973,11 @@ export default class Xo extends EventEmitter {
   }
 
   async _importVdiBackupContent (xapi, file, vdiId) {
-    const stream = fs.createReadStream(file)
+    const [ stream, length ] = await this._openAndwaitReadableFile(
-    const stats = await fs.stat(file)
+      file, 'VDI to import not found in this remote')
 
     await xapi.importVdiContent(vdiId, stream, {
-      length: stats.size,
+      length,
       format: Xapi.VDI_FORMAT_VHD
     })
   }
@@ -983,9 +1015,9 @@ export default class Xo extends EventEmitter {
 
   // -----------------------------------------------------------------
 
-  async _listDeltaVmBackups (path, tag, name_label) {
+  async _listDeltaVmBackups (path) {
     const files = await fs.readdir(path)
-    return await sortBy(filter(files, (fileName) => /^\d+T\d+Z\.(?:xva|json)$/.test(fileName)))
+    return await sortBy(filter(files, (fileName) => /^\d+T\d+Z_.*\.(?:xva|json)$/.test(fileName)))
   }
 
   // FIXME: Avoid bad files creation. (For example, exception during backup)
@@ -993,15 +1025,14 @@ export default class Xo extends EventEmitter {
   // The files are all vhd.
   async rollingDeltaVmBackup ({vm, remoteId, tag, depth}) {
     const remote = await this.getRemote(remoteId)
-    const directory = `vm_${tag}_${vm.uuid}`
+    const directory = `vm_delta_${tag}_${vm.uuid}`
     const path = `${remote.path}/${directory}`
 
     await fs.ensureDir(path)
 
     const info = {
       vbds: [],
-      vdis: {},
+      vdis: {}
-      name_label: vm.name_label
     }
 
     const promises = []
@@ -1040,11 +1071,12 @@ export default class Xo extends EventEmitter {
 
     await Promise.all(promises)
 
-    const backups = await this._listDeltaVmBackups(path, tag, vm.name_label)
+    const backups = await this._listDeltaVmBackups(path)
     const date = safeDateFormat(new Date())
+    const backupFormat = `${date}_${vm.name_label}`
 
-    const xvaPath = `${path}/${date}.xva`
+    const xvaPath = `${path}/${backupFormat}.xva`
-    const infoPath = `${path}/${date}.json`
+    const infoPath = `${path}/${backupFormat}.json`
 
     try {
       await Promise.all([
@@ -1060,14 +1092,13 @@ export default class Xo extends EventEmitter {
     await this._removeOldBackups(backups, path, backups.length - (depth - 1) * 2)
 
     // Returns relative path.
-    return `${directory}/${date}`
+    return `${directory}/${backupFormat}`
   }
 
   async _importVmMetadata (xapi, file) {
-    const stream = fs.createReadStream(file)
+    const [ stream, length ] = await this._openAndwaitReadableFile(
-    const stats = await fs.stat(file)
+      file, 'VM metadata to import not found in this remote')
-
+    return await xapi.importVm(stream, length, { onlyMetadata: true })
-    return await xapi.importVm(stream, stats.size, { onlyMetadata: true })
   }
 
   async _importDeltaVdiBackupFromVm (xapi, vmId, remoteId, directory, vdiInfo) {