fix: ability to create deleted file/directory again (#216)

* fix: ability to create deleted file/directory again

* fix: rebased

* fix: correct calculation of an epoch

* refactor: moved `deleteFeedData` to content-items

* fix: test data

src/account/mnemonic.ts

@@ -41,5 +41,5 @@ export async function uploadEncryptedMnemonic(
   assertUsername(username)
   assertBase64UrlData(encryptedMnemonic)
 
-  return writeFeedDataRaw(connection, username, stringToBytes(encryptedMnemonic), wallet.privateKey)
+  return writeFeedDataRaw(connection, username, stringToBytes(encryptedMnemonic), wallet)
 }

src/content-items/handler.ts

@@ -7,11 +7,12 @@ import { getRawDirectoryMetadataBytes } from '../directory/adapter'
 import { DIRECTORY_TOKEN, FILE_TOKEN } from '../file/handler'
 import { assertRawDirectoryMetadata, combine, splitPath } from '../directory/utils'
 import { RawDirectoryMetadata } from '../pod/types'
-import { assertItemIsNotExists, getRawMetadata } from './utils'
+import { deleteFeedData, getPathInfo, getRawMetadata } from './utils'
 import { RawMetadataWithEpoch } from './types'
 import { prepareEthAddress } from '../utils/wallet'
 import { PodPasswordBytes } from '../utils/encryption'
 import { DataUploadOptions } from '../file/types'
+import { getNextEpoch } from '../feed/lookup/utils'
 
 export const DEFAULT_UPLOAD_OPTIONS: DataUploadOptions = {
   blockSize: 1000000,
@@ -49,7 +50,6 @@ export async function addEntryToDirectory(
   const address = prepareEthAddress(wallet.address)
   const itemText = isFile ? 'File' : 'Directory'
   const fullPath = combine(...splitPath(parentPath), entryPath)
-  await assertItemIsNotExists(itemText, connection.bee, fullPath, address, downloadOptions)
 
   let parentData: RawDirectoryMetadata | undefined
   let metadataWithEpoch: RawMetadataWithEpoch | undefined
@@ -65,7 +65,7 @@ export async function addEntryToDirectory(
   parentData.fileOrDirNames = parentData.fileOrDirNames ?? []
 
   if (parentData.fileOrDirNames.includes(itemToAdd)) {
-    throw new Error(`${itemText} already listed in the parent directory list`)
+    throw new Error(`${itemText} "${fullPath}" already listed in the parent directory list`)
   }
 
   parentData.fileOrDirNames.push(itemToAdd)
@@ -75,12 +75,50 @@ export async function addEntryToDirectory(
     connection,
     parentPath,
     getRawDirectoryMetadataBytes(parentData),
-    wallet.privateKey,
+    wallet,
     podPassword,
-    metadataWithEpoch.epoch.getNextEpoch(getUnixTimestamp()),
+    getNextEpoch(metadataWithEpoch.epoch),
   )
 }
 
+/**
+ * Uploads magic word data on the next epoch's level
+ *
+ * Magic word should be uploaded if data is not found (in case of data pruning) or not deleted
+ */
+export async function deleteItem(
+  connection: Connection,
+  itemMetaPath: string,
+  wallet: utils.HDNode,
+  podPassword: PodPasswordBytes,
+): Promise<void> {
+  let pathInfo
+  try {
+    pathInfo = await getPathInfo(
+      connection.bee,
+      itemMetaPath,
+      prepareEthAddress(wallet.address),
+      connection.options?.requestOptions,
+    )
+    // eslint-disable-next-line no-empty
+  } catch (e) {}
+
+  // if the item already deleted - do nothing
+  if (pathInfo?.isDeleted) {
+    return
+  }
+
+  let metaPathEpoch
+
+  // if information is stored under the path, calculate the next level of epoch
+  if (pathInfo) {
+    pathInfo.lookupAnswer.epoch.level = pathInfo.lookupAnswer.epoch.getNextLevel(pathInfo.lookupAnswer.epoch.time)
+    metaPathEpoch = pathInfo.lookupAnswer.epoch
+  }
+
+  await deleteFeedData(connection, itemMetaPath, wallet, podPassword, metaPathEpoch)
+}
+
 /**
  * Removes file or directory from the parent directory
  *
@@ -111,17 +149,23 @@ export async function removeEntryFromDirectory(
   const parentData = metadataWithEpoch.metadata
   assertRawDirectoryMetadata(parentData)
   const itemToRemove = (isFile ? FILE_TOKEN : DIRECTORY_TOKEN) + entryPath
+  const fileOrDirNames = parentData.fileOrDirNames || []
 
-  if (parentData.fileOrDirNames) {
-    parentData.fileOrDirNames = parentData.fileOrDirNames.filter(name => name !== itemToRemove)
+  const fullPath = combine(parentPath, entryPath)
+
+  if (!fileOrDirNames.includes(itemToRemove)) {
+    throw new Error(`Item "${fullPath}" not found in the list of items`)
   }
 
+  parentData.fileOrDirNames = fileOrDirNames.filter(name => name !== itemToRemove)
+  await deleteItem(connection, fullPath, wallet, podPassword)
+
   return writeFeedData(
     connection,
     parentPath,
     getRawDirectoryMetadataBytes(parentData),
-    wallet.privateKey,
+    wallet,
     podPassword,
-    metadataWithEpoch.epoch.getNextEpoch(getUnixTimestamp()),
+    getNextEpoch(metadataWithEpoch.epoch),
   )
 }

src/content-items/types.ts

@@ -2,6 +2,17 @@ import { Epoch } from '../feed/lookup/epoch'
 import { RawDirectoryMetadata, RawFileMetadata } from '../pod/types'
 import { RequestOptions } from '@ethersphere/bee-js'
 import { CacheInfo } from '../cache/types'
+import { LookupAnswer } from '../feed/types'
+
+/**
+ * Information with the deletion status of the path
+ */
+export interface PathInformation {
+  // if the data under the path is the deletion magic word
+  isDeleted: boolean
+  // data `LookupAnswer`
+  lookupAnswer: LookupAnswer
+}
 
 /**
  * Download data options

src/content-items/utils.ts

@@ -1,11 +1,16 @@
 import { Bee, Reference, RequestOptions } from '@ethersphere/bee-js'
 import { EthAddress } from '@ethersphere/bee-js/dist/types/utils/eth'
 import { RawDirectoryMetadata, RawFileMetadata } from '../pod/types'
-import { getFeedData } from '../feed/api'
+import { DELETE_FEED_MAGIC_WORD, getFeedData, writeFeedData } from '../feed/api'
 import { isRawDirectoryMetadata, isRawFileMetadata } from '../directory/utils'
-import { DirectoryItem, FileItem, RawMetadataWithEpoch } from './types'
+import { DirectoryItem, FileItem, PathInformation, RawMetadataWithEpoch } from './types'
 import { decryptJson, PodPasswordBytes } from '../utils/encryption'
 import CryptoJS from 'crypto-js'
+import { isObject } from '../utils/type'
+import { Connection } from '../connection/connection'
+import { utils, Wallet } from 'ethers'
+import { Epoch } from '../feed/lookup/epoch'
+import { stringToBytes } from '../utils/bytes'
 
 /**
  * Get raw metadata by path
@@ -56,9 +61,7 @@ export async function isItemExists(
   requestOptions: RequestOptions | undefined,
 ): Promise<boolean> {
   try {
-    await getFeedData(bee, fullPath, address, requestOptions)
-
-    return true
+    return (await getFeedData(bee, fullPath, address, requestOptions)).data.text() === DELETE_FEED_MAGIC_WORD
   } catch (e) {
     return false
   }
@@ -118,3 +121,67 @@ export function rawFileMetadataToFileItem(item: RawFileMetadata): FileItem {
     reference,
   }
 }
+
+/**
+ * Gets `PathInformation` under the path
+ */
+export async function getPathInfo(
+  bee: Bee,
+  path: string,
+  address: EthAddress,
+  requestOptions?: RequestOptions,
+): Promise<PathInformation> {
+  const lookupAnswer = await getFeedData(bee, path, address, requestOptions)
+
+  return {
+    isDeleted: lookupAnswer.data.text() === DELETE_FEED_MAGIC_WORD,
+    lookupAnswer,
+  }
+}
+
+/**
+ * Asserts that metadata marked as deleted with the magic word
+ */
+export function assertItemDeleted(value: PathInformation, path: string): asserts value is PathInformation {
+  const data = value as PathInformation
+
+  if (!(isObject(data) && data.isDeleted)) {
+    throw new Error(`Item under the path "${path}" is not deleted`)
+  }
+}
+
+/**
+ * Gets `PathInformation` for creation and uploading metadata purposes
+ *
+ * In case metadata is available for uploading under the path, the method will return `PathInformation`.
+ * In other case it will return `undefined`.
+ */
+export async function getCreationPathInfo(
+  bee: Bee,
+  fullPath: string,
+  address: EthAddress,
+  requestOptions?: RequestOptions,
+): Promise<PathInformation | undefined> {
+  // check that if directory uploaded - than it should be marked as deleted
+  let pathInfo
+  try {
+    pathInfo = await getPathInfo(bee, fullPath, address, requestOptions)
+    assertItemDeleted(pathInfo, fullPath)
+    // eslint-disable-next-line no-empty
+  } catch (e) {}
+
+  return pathInfo
+}
+
+/**
+ * Deletes feed data for `topic` using owner's `wallet`
+ */
+export async function deleteFeedData(
+  connection: Connection,
+  topic: string,
+  wallet: utils.HDNode | Wallet,
+  podPassword: PodPasswordBytes,
+  epoch?: Epoch,
+): Promise<Reference> {
+  return writeFeedData(connection, topic, stringToBytes(DELETE_FEED_MAGIC_WORD), wallet, podPassword, epoch)
+}

src/directory/handler.ts

@@ -1,6 +1,6 @@
 import { writeFeedData } from '../feed/api'
 import { EthAddress } from '@ethersphere/bee-js/dist/types/utils/eth'
-import { Bee, PrivateKeyBytes, Reference, RequestOptions } from '@ethersphere/bee-js'
+import { Bee, Reference, RequestOptions } from '@ethersphere/bee-js'
 import {
   assertDirectoryName,
   assertPartsLength,
@@ -17,11 +17,18 @@ import { createRawDirectoryMetadata, META_VERSION } from '../pod/utils'
 import { Connection } from '../connection/connection'
 import { utils } from 'ethers'
 import { addEntryToDirectory, DEFAULT_UPLOAD_OPTIONS } from '../content-items/handler'
-import { rawDirectoryMetadataToDirectoryItem, rawFileMetadataToFileItem, getRawMetadata } from '../content-items/utils'
+import {
+  rawDirectoryMetadataToDirectoryItem,
+  rawFileMetadataToFileItem,
+  getRawMetadata,
+  getCreationPathInfo,
+} from '../content-items/utils'
 import { PodPasswordBytes } from '../utils/encryption'
-import { preparePrivateKey } from '../utils/wallet'
 import { DataUploadOptions } from '../file/types'
 import { DirectoryItem } from '../content-items/types'
+import { prepareEthAddress } from '../utils/wallet'
+import { Epoch } from '../feed/lookup/epoch'
+import { getNextEpoch } from '../feed/lookup/utils'
 
 /**
  * Options for uploading a directory
@@ -107,34 +114,36 @@ export async function readDirectory(
  * @param path parent path
  * @param name name of the directory
  * @param podPassword bytes for data encryption from pod metadata
- * @param privateKey private key for uploading data to the network
+ * @param wallet feed owner's wallet
+ * @param epoch epoch where directory info should be uploaded
  */
 async function createDirectoryInfo(
   connection: Connection,
   path: string,
   name: string,
   podPassword: PodPasswordBytes,
-  privateKey: PrivateKeyBytes,
+  wallet: utils.HDNode,
+  epoch?: Epoch,
 ): Promise<Reference> {
   const now = getUnixTimestamp()
   const metadata = createRawDirectoryMetadata(META_VERSION, path, name, now, now, now)
 
-  return writeFeedData(connection, combine(...splitPath(path), name), metadata, privateKey, podPassword)
+  return writeFeedData(connection, combine(...splitPath(path), name), metadata, wallet, podPassword, epoch)
 }
 
 /**
  * Creates root directory for the pod that tied to the private key
  *
  * @param connection Bee connection
  * @param podPassword bytes for data encryption
- * @param privateKey private key for uploading data to the network
+ * @param wallet feed owner's wallet
  */
 export async function createRootDirectory(
   connection: Connection,
   podPassword: PodPasswordBytes,
-  privateKey: PrivateKeyBytes,
+  wallet: utils.HDNode,
 ): Promise<Reference> {
-  return createDirectoryInfo(connection, '', '/', podPassword, privateKey)
+  return createDirectoryInfo(connection, '', '/', podPassword, wallet)
 }
 
 /**
@@ -158,8 +167,20 @@ export async function createDirectory(
   const name = parts[parts.length - 1]
   assertDirectoryName(name)
 
-  const privateKey = preparePrivateKey(podWallet.privateKey)
   const parentPath = getPathFromParts(parts, 1)
+  const pathInfo = await getCreationPathInfo(
+    connection.bee,
+    fullPath,
+    prepareEthAddress(podWallet.address),
+    connection.options?.requestOptions,
+  )
   await addEntryToDirectory(connection, podWallet, podPassword, parentPath, name, false, downloadOptions)
-  await createDirectoryInfo(connection, parentPath, name, podPassword, privateKey)
+  await createDirectoryInfo(
+    connection,
+    parentPath,
+    name,
+    podPassword,
+    podWallet,
+    getNextEpoch(pathInfo?.lookupAnswer.epoch),
+  )
 }