Signal-iOS/SignalServiceKit/MessageBackup/MessageBackupManagerImpl.swift
2023-12-19 13:29:34 -08:00

289 lines
11 KiB
Swift

//
// Copyright 2023 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
//
import Foundation
import LibSignalClient
public class NotImplementedError: Error {}
public class MessageBackupManagerImpl: MessageBackupManager {
private let chatArchiver: MessageBackupChatArchiver
private let chatItemArchiver: MessageBackupChatItemArchiver
private let dateProvider: DateProvider
private let db: DB
private let recipientArchiver: MessageBackupRecipientArchiver
private let streamProvider: MessageBackupProtoStreamProvider
private let tsAccountManager: TSAccountManager
public init(
chatArchiver: MessageBackupChatArchiver,
chatItemArchiver: MessageBackupChatItemArchiver,
dateProvider: @escaping DateProvider,
db: DB,
recipientArchiver: MessageBackupRecipientArchiver,
streamProvider: MessageBackupProtoStreamProvider,
tsAccountManager: TSAccountManager
) {
self.chatArchiver = chatArchiver
self.chatItemArchiver = chatItemArchiver
self.dateProvider = dateProvider
self.db = db
self.recipientArchiver = recipientArchiver
self.streamProvider = streamProvider
self.tsAccountManager = tsAccountManager
}
public func createBackup() async throws -> URL {
guard FeatureFlags.messageBackupFileAlpha else {
owsFailDebug("Should not be able to use backups!")
throw NotImplementedError()
}
return try await db.awaitableWrite { tx in
// The mother of all write transactions. Eventually we want to use
// a read tx, and use explicit locking to prevent other things from
// happening in the meantime (e.g. message processing) but for now
// hold the single write lock and call it a day.
return try self._createBackup(tx: tx)
}
}
public func importBackup(fileUrl: URL) async throws {
guard FeatureFlags.messageBackupFileAlpha else {
owsFailDebug("Should not be able to use backups!")
throw NotImplementedError()
}
try await db.awaitableWrite { tx in
// This has to open one big write transaction; the alternative is
// to chunk them into separate writes. Nothing else should be happening
// in the app anyway.
do {
try self._importBackup(fileUrl, tx: tx)
} catch let error {
owsFailDebug("Failed! \(error)")
throw error
}
}
}
private func _createBackup(tx: DBWriteTransaction) throws -> URL {
let stream: MessageBackupProtoOutputStream
switch streamProvider.openOutputFileStream() {
case .success(let streamResult):
stream = streamResult
case .unableToOpenFileStream:
throw OWSAssertionError("Unable to open output stream")
}
guard let localIdentifiers = tsAccountManager.localIdentifiers(tx: tx) else {
throw OWSAssertionError("No local identifiers!")
}
let recipientArchivingContext = MessageBackup.RecipientArchivingContext(
localIdentifiers: localIdentifiers
)
try writeHeader(stream: stream, tx: tx)
let recipientArchiveResult = recipientArchiver.archiveRecipients(
stream: stream,
context: recipientArchivingContext,
tx: tx
)
switch recipientArchiveResult {
case .success:
break
case .partialSuccess(let partialFailures):
// TODO: how many failures is too many?
Logger.warn("Failed to serialize \(partialFailures.count) recipients")
case .completeFailure(let error):
throw error
}
let chatArchivingContext = MessageBackup.ChatArchivingContext(
recipientContext: recipientArchivingContext
)
let chatArchiveResult = chatArchiver.archiveChats(
stream: stream,
context: chatArchivingContext,
tx: tx
)
switch chatArchiveResult {
case .success:
break
case .partialSuccess(let partialFailures):
// TODO: how many failures is too many?
Logger.warn("Failed to serialize \(partialFailures.count) chats")
case .completeFailure(let error):
throw error
}
let chatItemArchiveResult = chatItemArchiver.archiveInteractions(
stream: stream,
context: chatArchivingContext,
tx: tx
)
switch chatItemArchiveResult {
case .success:
break
case .partialSuccess(let partialFailures):
// TODO: how many failures is too many?
Logger.warn("Failed to serialize \(partialFailures.count) chat items")
case .completeFailure(let error):
throw error
}
return stream.closeFileStream()
}
private func writeHeader(stream: MessageBackupProtoOutputStream, tx: DBWriteTransaction) throws {
let backupInfo = try BackupProtoBackupInfo.builder(
version: 1,
backupTimeMs: dateProvider().ows_millisecondsSince1970
).build()
switch stream.writeHeader(backupInfo) {
case .success:
break
case .fileIOError(let error), .protoSerializationError(let error):
throw error
}
}
private func _importBackup(_ fileUrl: URL, tx: DBWriteTransaction) throws {
guard let localIdentifiers = tsAccountManager.localIdentifiers(tx: tx) else {
throw OWSAssertionError("No local identifiers!")
}
let stream: MessageBackupProtoInputStream
switch streamProvider.openInputFileStream(fileURL: fileUrl) {
case .success(let streamResult):
stream = streamResult
case .fileNotFound:
throw OWSAssertionError("file not found!")
case .unableToOpenFileStream:
throw OWSAssertionError("unable to open input stream")
}
defer {
stream.closeFileStream()
}
let backupInfo: BackupProtoBackupInfo
var hasMoreFrames = false
switch stream.readHeader() {
case .success(let header, let moreBytesAvailable):
backupInfo = header
hasMoreFrames = moreBytesAvailable
case .invalidByteLengthDelimiter:
throw OWSAssertionError("invalid byte length delimiter on header")
case .protoDeserializationError(let error):
// Fail if we fail to deserialize the header.
throw error
}
Logger.info("Reading backup with version: \(backupInfo.version) backed up at \(backupInfo.backupTimeMs)")
let recipientContext = MessageBackup.RecipientRestoringContext(localIdentifiers: localIdentifiers)
let chatContext = MessageBackup.ChatRestoringContext(
recipientContext: recipientContext
)
while hasMoreFrames {
let frame: BackupProtoFrame
switch stream.readFrame() {
case let .success(_frame, moreBytesAvailable):
frame = _frame
hasMoreFrames = moreBytesAvailable
case .invalidByteLengthDelimiter:
throw OWSAssertionError("invalid byte length delimiter on header")
case .protoDeserializationError(let error):
// TODO: should we fail the whole thing if we fail to deserialize one frame?
throw error
}
if let recipient = frame.recipient {
let recipientResult = recipientArchiver.restore(
recipient,
context: recipientContext,
tx: tx
)
switch recipientResult {
case .success:
continue
case .partialRestore(let id, let errors):
try processRestoreFrameErrors(id: id, errors: errors, context: chatContext)
case .failure(let id, let errors):
try processRestoreFrameErrors(id: id, errors: errors, context: chatContext)
}
} else if let chat = frame.chat {
let chatResult = chatArchiver.restore(
chat,
context: chatContext,
tx: tx
)
switch chatResult {
case .success:
continue
case .partialRestore(let id, let errors):
try processRestoreFrameErrors(id: id, errors: errors, context: chatContext)
case .failure(let id, let errors):
try processRestoreFrameErrors(id: id, errors: errors, context: chatContext)
}
} else if let chatItem = frame.chatItem {
let chatItemResult = chatItemArchiver.restore(
chatItem,
context: chatContext,
tx: tx
)
switch chatItemResult {
case .success:
continue
case .partialRestore(let id, let errors):
try processRestoreFrameErrors(id: id, errors: errors, context: chatContext)
case .failure(let id, let errors):
try processRestoreFrameErrors(id: id, errors: errors, context: chatContext)
}
}
}
return stream.closeFileStream()
}
private func processRestoreFrameErrors<IdType>(
id: IdType,
errors: [MessageBackup.RestoringFrameError],
context: MessageBackup.ChatRestoringContext
) throws {
try errors.forEach { error in
// TODO: we shouldn't throw on every error, especially
// those from successWithWarnings cases.
switch error {
case .databaseInsertionFailed(let dbError):
throw dbError
case .invalidProtoData:
throw OWSAssertionError("Invalid proto data for id: \(id)")
case .identifierNotFound(let referencedId):
// TODO: aggregate these errors; at the end we should be able to say
// some set of IDs were referenced but not found or failed to process.
switch referencedId {
case .chat(let chatId):
throw OWSAssertionError("Did not find chat id: \(chatId) referenced from: \(id)")
case .recipient(let recipientId):
throw OWSAssertionError("Did not find recipient id: \(recipientId) referenced from: \(id)")
}
case .referencedDatabaseObjectNotFound(let referencedId):
switch referencedId {
case .thread(let threadUniqueId):
throw OWSAssertionError("Did not find thread: \(threadUniqueId) referenced from: \(id)")
case .groupThread(let groupId):
throw OWSAssertionError("Did not find thread with group id: \(groupId) referenced from: \(id)")
}
case .unknownFrameType:
throw OWSAssertionError("Found unrecognized frame type with id: \(id)")
case .unimplemented:
// Ignore unimplemented errors.
break
}
}
}
}