Remove support for building dynamic patches on Android. (#31359)

packages/flutter_tools/lib/src/android/gradle.dart

@@ -4,12 +4,9 @@
 
 import 'dart:async';
 
-import 'package:archive/archive.dart';
-import 'package:bsdiff/bsdiff.dart';
 import 'package:meta/meta.dart';
 
 import '../android/android_sdk.dart';
-import '../application_package.dart';
 import '../artifacts.dart';
 import '../base/common.dart';
 import '../base/file_system.dart';
@@ -20,7 +17,6 @@ import '../base/process.dart';
 import '../base/utils.dart';
 import '../build_info.dart';
 import '../cache.dart';
-import '../convert.dart';
 import '../flutter_manifest.dart';
 import '../globals.dart';
 import '../project.dart';
@@ -425,8 +421,6 @@ Future<void> _buildGradleProjectV2(
   command.add('-Ptrack-widget-creation=${buildInfo.trackWidgetCreation}');
   if (buildInfo.compilationTraceFilePath != null)
     command.add('-Pcompilation-trace-file=${buildInfo.compilationTraceFilePath}');
-  if (buildInfo.createPatch)
-    command.add('-Ppatch=true');
   if (buildInfo.extraFrontEndOptions != null)
     command.add('-Pextra-front-end-options=${buildInfo.extraFrontEndOptions}');
   if (buildInfo.extraGenSnapshotOptions != null)
@@ -497,105 +491,6 @@ Future<void> _buildGradleProjectV2(
     }
     printStatus('Built ${fs.path.relative(apkFile.path)}$appSize.');
 
-    if (buildInfo.createBaseline) {
-      // Save baseline apk for generating dynamic patches in later builds.
-      final AndroidApk package = AndroidApk.fromApk(apkFile);
-      final Directory baselineDir = fs.directory(buildInfo.baselineDir);
-      final File baselineApkFile = baselineDir.childFile('${package.versionCode}.apk');
-      baselineApkFile.parent.createSync(recursive: true);
-      apkFile.copySync(baselineApkFile.path);
-      printStatus('Saved baseline package ${baselineApkFile.path}.');
-    }
-
-    if (buildInfo.createPatch) {
-      final AndroidApk package = AndroidApk.fromApk(apkFile);
-      final Directory baselineDir = fs.directory(buildInfo.baselineDir);
-      final File baselineApkFile = baselineDir.childFile('${package.versionCode}.apk');
-      if (!baselineApkFile.existsSync())
-        throwToolExit('Error: Could not find baseline package ${baselineApkFile.path}.');
-
-      printStatus('Found baseline package ${baselineApkFile.path}.');
-      printStatus('Creating dynamic patch...');
-      final Archive newApk = ZipDecoder().decodeBytes(apkFile.readAsBytesSync());
-      final Archive oldApk = ZipDecoder().decodeBytes(baselineApkFile.readAsBytesSync());
-
-      final Archive update = Archive();
-      for (ArchiveFile newFile in newApk) {
-        if (!newFile.isFile)
-          continue;
-
-        // Ignore changes to signature manifests.
-        if (newFile.name.startsWith('META-INF/'))
-          continue;
-
-        final ArchiveFile oldFile = oldApk.findFile(newFile.name);
-        if (oldFile != null && oldFile.crc32 == newFile.crc32)
-          continue;
-
-        // Only allow certain changes.
-        if (!newFile.name.startsWith('assets/') &&
-            !(buildInfo.usesAot && newFile.name.endsWith('.so')))
-          throwToolExit("Error: Dynamic patching doesn't support changes to ${newFile.name}.");
-
-        final String name = newFile.name;
-        if (name.contains('_snapshot_') || name.endsWith('.so')) {
-          final List<int> diff = bsdiff(oldFile.content, newFile.content);
-          final int ratio = 100 * diff.length ~/ newFile.content.length;
-          printStatus('Deflated $name by ${ratio == 0 ? 99 : 100 - ratio}%');
-          update.addFile(ArchiveFile(name + '.bzdiff40', diff.length, diff));
-        } else {
-          update.addFile(ArchiveFile(name, newFile.content.length, newFile.content));
-        }
-      }
-
-      File updateFile;
-      if (buildInfo.patchNumber != null) {
-        updateFile = fs.directory(buildInfo.patchDir)
-            .childFile('${package.versionCode}-${buildInfo.patchNumber}.zip');
-      } else {
-        updateFile = fs.directory(buildInfo.patchDir)
-            .childFile('${package.versionCode}.zip');
-      }
-
-      if (update.files.isEmpty) {
-        printStatus('No changes detected, creating rollback patch.');
-      }
-
-      final List<String> checksumFiles = <String>[
-        'assets/isolate_snapshot_data',
-        'assets/isolate_snapshot_instr',
-        'assets/flutter_assets/isolate_snapshot_data',
-      ];
-
-      int baselineChecksum = 0;
-      for (String fn in checksumFiles) {
-        final ArchiveFile oldFile = oldApk.findFile(fn);
-        if (oldFile != null)
-          baselineChecksum = getCrc32(oldFile.content, baselineChecksum);
-      }
-      if (baselineChecksum == 0)
-        throwToolExit('Error: Could not find baseline VM snapshot.');
-
-      final Map<String, dynamic> manifest = <String, dynamic>{
-        'baselineChecksum': baselineChecksum,
-        'buildNumber': package.versionCode,
-      };
-
-      if (buildInfo.patchNumber != null) {
-        manifest.addAll(<String, dynamic>{
-          'patchNumber': buildInfo.patchNumber,
-        });
-      }
-
-      const JsonEncoder encoder = JsonEncoder.withIndent('  ');
-      final String manifestJson = encoder.convert(manifest);
-      update.addFile(ArchiveFile('manifest.json', manifestJson.length, manifestJson.codeUnits));
-
-      updateFile.parent.createSync(recursive: true);
-      updateFile.writeAsBytesSync(ZipEncoder().encode(update), flush: true);
-      final String patchSize = getSizeAsMB(updateFile.lengthSync());
-      printStatus('Created dynamic patch ${updateFile.path} ($patchSize).');
-    }
   } else {
     final File bundleFile = _findBundleFile(project, buildInfo);
     if (bundleFile == null)

packages/flutter_tools/lib/src/base/build.dart

@@ -4,8 +4,6 @@
 
 import 'dart:async';
 
-import 'package:archive/archive.dart';
-import 'package:collection/collection.dart';
 import 'package:meta/meta.dart';
 
 import '../android/android_sdk.dart';
@@ -378,9 +376,6 @@ class JITSnapshotter {
     @required String packagesPath,
     @required String outputPath,
     @required String compilationTraceFilePath,
-    @required bool createPatch,
-    String buildNumber,
-    String baselineDir,
     List<String> extraGenSnapshotOptions = const <String>[],
   }) async {
     if (!_isValidJitPlatform(platform)) {
@@ -400,83 +395,6 @@ class JITSnapshotter {
       mainPath, compilationTraceFilePath, engineVmSnapshotData, engineIsolateSnapshotData,
     ];
 
-    if (createPatch) {
-      inputPaths.add(isolateSnapshotInstructions);
-
-      if (buildNumber == null) {
-        printError('Error: Dynamic patching requires --build-number specified');
-        return 1;
-      }
-      if (baselineDir == null) {
-        printError('Error: Dynamic patching requires --baseline-dir specified');
-        return 1;
-      }
-
-      final File baselineApk = fs.directory(baselineDir).childFile('$buildNumber.apk');
-      if (!baselineApk.existsSync()) {
-        printError('Error: Could not find baseline package ${baselineApk.path}.');
-        return 1;
-      }
-
-      final Archive baselinePkg = ZipDecoder().decodeBytes(baselineApk.readAsBytesSync());
-
-      {
-        final File f = fs.file(isolateSnapshotInstructions);
-        final ArchiveFile af = baselinePkg.findFile(
-            fs.path.join('assets/flutter_assets/isolate_snapshot_instr'));
-        if (af == null) {
-          printError('Error: Invalid baseline package ${baselineApk.path}.');
-          return 1;
-        }
-
-        // When building an update, gen_snapshot expects to find the original isolate
-        // snapshot instructions from the previous full build, so we need to extract
-        // it from saves baseline APK.
-        if (!f.existsSync()) {
-          f.writeAsBytesSync(af.content, flush: true);
-        } else {
-          // But if this file is already extracted, we make sure that it's identical.
-          final Function contentEquals = const ListEquality<int>().equals;
-          if (!contentEquals(f.readAsBytesSync(), af.content)) {
-            printError('Error: Detected changes unsupported by dynamic patching.');
-            return 1;
-          }
-        }
-      }
-
-      {
-        final File f = fs.file(engineVmSnapshotData);
-        final ArchiveFile af = baselinePkg.findFile(
-            fs.path.join('assets/flutter_assets/vm_snapshot_data'));
-        if (af == null) {
-          printError('Error: Invalid baseline package ${baselineApk.path}.');
-          return 1;
-        }
-
-        // If engine snapshot artifact doesn't exist, gen_snapshot below will fail
-        // with a friendly error, so we don't need to handle this case here too.
-        if (f.existsSync()) {
-          // But if engine snapshot exists, its content must match the engine snapshot
-          // in baseline APK. Otherwise, we're trying to build an update at an engine
-          // version that might be binary incompatible with baseline APK.
-          final Function contentEquals = const ListEquality<int>().equals;
-          if (!contentEquals(f.readAsBytesSync(), af.content)) {
-            printError('Error: Detected engine changes unsupported by dynamic patching.');
-            return 1;
-          }
-        }
-      }
-
-      {
-        final ArchiveFile af = baselinePkg.findFile(
-            fs.path.join('assets/flutter_assets/vm_snapshot_instr'));
-        if (af != null) {
-          printError('Error: Invalid baseline package ${baselineApk.path}.');
-          return 1;
-        }
-      }
-    }
-
     final String depfilePath = fs.path.join(outputDir.path, 'snapshot.d');
     final List<String> genSnapshotArgs = <String>[
       '--deterministic',
@@ -490,10 +408,7 @@ class JITSnapshotter {
     }
 
     final Set<String> outputPaths = <String>{};
-    outputPaths.addAll(<String>[isolateSnapshotData]);
-    if (!createPatch) {
-      outputPaths.add(isolateSnapshotInstructions);
-    }
+    outputPaths.addAll(<String>[isolateSnapshotData, isolateSnapshotInstructions]);
 
     // There are a couple special cases below where we create a snapshot
     // with only the data section, which only contains interpreted code.
@@ -520,11 +435,7 @@ class JITSnapshotter {
       '--isolate_snapshot_data=$isolateSnapshotData',
     ]);
 
-    if (!createPatch) {
     genSnapshotArgs.add('--isolate_snapshot_instructions=$isolateSnapshotInstructions');
-    } else {
-      genSnapshotArgs.add('--reused_instructions=$isolateSnapshotInstructions');
-    }
 
     if (platform == TargetPlatform.android_arm) {
       // Use softfp for Android armv7 devices.
@@ -552,7 +463,6 @@ class JITSnapshotter {
         'buildMode': buildMode.toString(),
         'targetPlatform': platform.toString(),
         'entryPoint': mainPath,
-        'createPatch': createPatch.toString(),
         'extraGenSnapshotOptions': extraGenSnapshotOptions.join(' '),
       },
       depfilePaths: <String>[],

packages/flutter_tools/lib/src/build_info.dart

@@ -15,11 +15,6 @@ class BuildInfo {
     this.flavor, {
     this.trackWidgetCreation = false,
     this.compilationTraceFilePath,
-    this.createBaseline = false,
-    this.createPatch = false,
-    this.patchNumber,
-    this.patchDir,
-    this.baselineDir,
     this.extraFrontEndOptions,
     this.extraGenSnapshotOptions,
     this.buildSharedLibrary,
@@ -49,25 +44,6 @@ class BuildInfo {
   /// Dart compilation trace file to use for JIT VM snapshot.
   final String compilationTraceFilePath;
 
-  /// Save baseline package.
-  final bool createBaseline;
-
-  /// Build differential snapshot.
-  final bool createPatch;
-
-  /// Internal version number of dynamic patch (not displayed to users).
-  /// Each patch may have a unique number to differentiate from previous
-  /// patches for the same versionCode on Android or CFBundleVersion on iOS.
-  final int patchNumber;
-
-  /// The directory where to store generated dynamic patches.
-  final String patchDir;
-
-  /// The directory where to store generated baseline packages.
-  /// Built packages, such as APK files on Android, are saved and can be used
-  /// to generate dynamic patches in later builds.
-  final String baselineDir;
-
   /// Extra command-line options for front-end.
   final String extraFrontEndOptions;
 
@@ -127,7 +103,6 @@ class BuildInfo {
       BuildInfo(mode, flavor,
           trackWidgetCreation: trackWidgetCreation,
           compilationTraceFilePath: compilationTraceFilePath,
-          createPatch: createPatch,
           extraFrontEndOptions: extraFrontEndOptions,
           extraGenSnapshotOptions: extraGenSnapshotOptions,
           buildSharedLibrary: buildSharedLibrary,

packages/flutter_tools/lib/src/bundle.dart

@@ -61,9 +61,6 @@ Future<void> build({
   bool reportLicensedPackages = false,
   bool trackWidgetCreation = false,
   String compilationTraceFilePath,
-  bool createPatch = false,
-  String buildNumber,
-  String baselineDir,
   List<String> extraFrontEndOptions = const <String>[],
   List<String> extraGenSnapshotOptions = const <String>[],
   List<String> fileSystemRoots,
@@ -134,9 +131,6 @@ Future<void> build({
         packagesPath: packagesPath,
         compilationTraceFilePath: compilationTraceFilePath,
         extraGenSnapshotOptions: extraGenSnapshotOptions,
-        createPatch: createPatch,
-        buildNumber: buildNumber,
-        baselineDir: baselineDir,
       );
       if (snapshotExitCode != 0) {
         throwToolExit('Snapshotting exited with non-zero exit code: $snapshotExitCode');

packages/flutter_tools/lib/src/commands/build_apk.dart

@@ -14,7 +14,6 @@ class BuildApkCommand extends BuildSubCommand {
     usesTargetOption();
     addBuildModeFlags(verboseHelp: verboseHelp);
     addDynamicModeFlags(verboseHelp: verboseHelp);
-    addDynamicPatchingFlags(verboseHelp: verboseHelp);
     usesFlavorOption();
     usesPubOption();
     usesBuildNumberOption();

packages/flutter_tools/lib/src/commands/build_bundle.dart

@@ -17,7 +17,6 @@ class BuildBundleCommand extends BuildSubCommand {
     usesBuildNumberOption();
     addBuildModeFlags(verboseHelp: verboseHelp);
     addDynamicModeFlags(verboseHelp: verboseHelp);
-    addDynamicBaselineFlags(verboseHelp: verboseHelp);
     argParser
       ..addFlag('precompiled', negatable: false)
       // This option is still referenced by the iOS build scripts. We should
@@ -70,8 +69,6 @@ class BuildBundleCommand extends BuildSubCommand {
 
     final BuildMode buildMode = getBuildMode();
 
-    final String buildNumber = argResults['build-number'] != null ? argResults['build-number'] : null;
-
     await build(
       platform: platform,
       buildMode: buildMode,
@@ -84,9 +81,6 @@ class BuildBundleCommand extends BuildSubCommand {
       reportLicensedPackages: argResults['report-licensed-packages'],
       trackWidgetCreation: argResults['track-widget-creation'],
       compilationTraceFilePath: argResults['compilation-trace-file'],
-      createPatch: argResults['patch'],
-      buildNumber: buildNumber,
-      baselineDir: argResults['baseline-dir'],
       extraFrontEndOptions: argResults[FlutterOptions.kExtraFrontEndOptions],
       extraGenSnapshotOptions: argResults[FlutterOptions.kExtraGenSnapshotOptions],
       fileSystemScheme: argResults['filesystem-scheme'],

packages/flutter_tools/lib/src/commands/run.dart

@@ -25,7 +25,6 @@ abstract class RunCommandBase extends FlutterCommand with DeviceBasedDevelopment
   RunCommandBase({ bool verboseHelp = false }) {
     addBuildModeFlags(defaultToRelease: false, verboseHelp: verboseHelp);
     addDynamicModeFlags(verboseHelp: verboseHelp);
-    addDynamicPatchingFlags(verboseHelp: verboseHelp);
     usesFlavorOption();
     argParser
       ..addFlag('trace-startup',

packages/flutter_tools/lib/src/runner/flutter_command.dart

@@ -259,54 +259,6 @@ abstract class FlutterCommand extends Command<void> {
               '--dynamic builds such as \'flutter build apk --dynamic\' to precompile\n'
               'some code by the offline compiler.',
     );
-    argParser.addFlag('patch',
-        hide: !verboseHelp,
-        negatable: false,
-        help: 'Generate dynamic patch for current changes from baseline.\n'
-              'Dynamic patch is generated relative to baseline package.\n'
-              'This flag is only allowed when using --dynamic.\n',
-    );
-  }
-
-  void addDynamicPatchingFlags({ bool verboseHelp = false }) {
-    argParser.addOption('patch-number',
-        hide: !verboseHelp,
-        help: 'An integer used as an internal version number for dynamic patch.\n'
-              'Each update may have a unique number to differentiate from previous\n'
-              'patches for same \'versionCode\' on Android or \'CFBundleVersion\' on iOS.\n'
-              'This optional setting allows several dynamic patches to coexist\n'
-              'for same baseline build, and is useful for canary and A-B testing\n'
-              'of dynamic patches.\n'
-              'This flag is only used when --dynamic --patch is specified.\n',
-    );
-    argParser.addOption('patch-dir',
-        defaultsTo: 'public',
-        hide: !verboseHelp,
-        help: 'The directory where to store generated dynamic patches.\n'
-              'This directory can be deployed to a CDN such as Firebase Hosting.\n'
-              'It is recommended to store this directory in version control.\n'
-              'This flag is only used when --dynamic --patch is specified.\n',
-    );
-    argParser.addFlag('baseline',
-        hide: !verboseHelp,
-        negatable: false,
-        help: 'Save built package as baseline for future dynamic patching.\n'
-            'Built package, such as APK file on Android, is saved and '
-            'can be used to generate dynamic patches in later builds.\n'
-            'This flag is only allowed when using --dynamic.\n',
-    );
-
-    addDynamicBaselineFlags(verboseHelp: verboseHelp);
-  }
-
-  void addDynamicBaselineFlags({ bool verboseHelp = false }) {
-    argParser.addOption('baseline-dir',
-        defaultsTo: '.baseline',
-        hide: !verboseHelp,
-        help: 'The directory where to store and find generated baseline packages.\n'
-              'It is recommended to store this directory in version control.\n'
-              'This flag is only used when --dynamic --baseline is specified.\n',
-    );
   }
 
   void usesFuchsiaOptions({ bool hide = false }) {
@@ -382,16 +334,6 @@ abstract class FlutterCommand extends Command<void> {
         ? argResults['build-number']
         : null;
 
-    int patchNumber;
-    try {
-      patchNumber = argParser.options.containsKey('patch-number') && argResults['patch-number'] != null
-          ? int.parse(argResults['patch-number'])
-          : null;
-    } catch (e) {
-      throw UsageException(
-          '--patch-number (${argResults['patch-number']}) must be an int.', null);
-    }
-
     String extraFrontEndOptions =
         argParser.options.containsKey(FlutterOptions.kExtraFrontEndOptions)
             ? argResults[FlutterOptions.kExtraFrontEndOptions]
@@ -416,19 +358,6 @@ abstract class FlutterCommand extends Command<void> {
       compilationTraceFilePath: argParser.options.containsKey('compilation-trace-file')
           ? argResults['compilation-trace-file']
           : null,
-      createBaseline: argParser.options.containsKey('baseline')
-          ? argResults['baseline']
-          : false,
-      createPatch: argParser.options.containsKey('patch')
-          ? argResults['patch']
-          : false,
-      patchNumber: patchNumber,
-      patchDir: argParser.options.containsKey('patch-dir')
-          ? argResults['patch-dir']
-          : null,
-      baselineDir: argParser.options.containsKey('baseline-dir')
-          ? argResults['baseline-dir']
-          : null,
       extraFrontEndOptions: extraFrontEndOptions,
       extraGenSnapshotOptions: argParser.options.containsKey(FlutterOptions.kExtraGenSnapshotOptions)
           ? argResults[FlutterOptions.kExtraGenSnapshotOptions]
@@ -670,20 +599,6 @@ abstract class FlutterCommand extends Command<void> {
       if (!fs.isFileSync(targetPath))
         throw ToolExit(userMessages.flutterTargetFileMissing(targetPath));
     }
-
-    final String compilationTraceFilePath = argParser.options.containsKey('compilation-trace-file')
-        ? argResults['compilation-trace-file'] : null;
-    final bool createBaseline = argParser.options.containsKey('baseline')
-        ? argResults['baseline'] : false;
-    final bool createPatch = argParser.options.containsKey('patch')
-        ? argResults['patch'] : false;
-
-    if (createBaseline && createPatch)
-      throw ToolExit(userMessages.flutterBasePatchFlagsExclusive);
-    if (createBaseline && compilationTraceFilePath == null)
-      throw ToolExit(userMessages.flutterBaselineRequiresTraceFile);
-    if (createPatch && compilationTraceFilePath == null)
-      throw ToolExit(userMessages.flutterPatchRequiresTraceFile);
   }
 
   ApplicationPackageStore applicationPackages;