blob: 8891428f2b05f64117fcee0fec5300df5d46b464 [file] [log] [blame]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:typed_data';
import '../base/file_system.dart';
import '../base/utils.dart';
import '../convert.dart';
/// A pseudo-filesystem stored in memory.
///
/// To support output to arbitrary multi-root file schemes, the frontend server
/// will output web sources, sourcemaps, and metadata to concatenated single files
/// with an additional manifest file containing the correct offsets.
class WebMemoryFS {
final Map<String, Uint8List> metadataFiles = <String, Uint8List>{};
final Map<String, Uint8List> files = <String, Uint8List>{};
final Map<String, Uint8List> sourcemaps = <String, Uint8List>{};
String? get mergedMetadata => _mergedMetadata;
String? _mergedMetadata;
/// Update the filesystem with the provided source and manifest files.
///
/// Returns the list of updated files.
List<String> write(
File codeFile,
File manifestFile,
File sourcemapFile,
File metadataFile,
) {
final List<String> modules = <String>[];
final Uint8List codeBytes = codeFile.readAsBytesSync();
final Uint8List sourcemapBytes = sourcemapFile.readAsBytesSync();
final Uint8List metadataBytes = metadataFile.readAsBytesSync();
final Map<String, dynamic> manifest =
castStringKeyedMap(json.decode(manifestFile.readAsStringSync()))!;
for (final String filePath in manifest.keys) {
if (filePath == null) {
continue;
}
final Map<String, dynamic> offsets =
castStringKeyedMap(manifest[filePath])!;
final List<int> codeOffsets =
(offsets['code'] as List<dynamic>).cast<int>();
final List<int> sourcemapOffsets =
(offsets['sourcemap'] as List<dynamic>).cast<int>();
final List<int> metadataOffsets =
(offsets['metadata'] as List<dynamic>).cast<int>();
if (codeOffsets.length != 2 ||
sourcemapOffsets.length != 2 ||
metadataOffsets.length != 2) {
continue;
}
final int codeStart = codeOffsets[0];
final int codeEnd = codeOffsets[1];
if (codeStart < 0 || codeEnd > codeBytes.lengthInBytes) {
continue;
}
final Uint8List byteView = Uint8List.view(
codeBytes.buffer,
codeStart,
codeEnd - codeStart,
);
final String fileName =
filePath.startsWith('/') ? filePath.substring(1) : filePath;
files[fileName] = byteView;
final int sourcemapStart = sourcemapOffsets[0];
final int sourcemapEnd = sourcemapOffsets[1];
if (sourcemapStart < 0 || sourcemapEnd > sourcemapBytes.lengthInBytes) {
continue;
}
final Uint8List sourcemapView = Uint8List.view(
sourcemapBytes.buffer,
sourcemapStart,
sourcemapEnd - sourcemapStart,
);
final String sourcemapName = '$fileName.map';
sourcemaps[sourcemapName] = sourcemapView;
final int metadataStart = metadataOffsets[0];
final int metadataEnd = metadataOffsets[1];
if (metadataStart < 0 || metadataEnd > metadataBytes.lengthInBytes) {
continue;
}
final Uint8List metadataView = Uint8List.view(
metadataBytes.buffer,
metadataStart,
metadataEnd - metadataStart,
);
final String metadataName = '$fileName.metadata';
metadataFiles[metadataName] = metadataView;
modules.add(fileName);
}
_mergedMetadata = metadataFiles.values
.map((Uint8List encoded) => utf8.decode(encoded))
.join('\n');
return modules;
}
}