delete old log file if it exceeds kMaxLogFileSize of 25MiB (#277)

* delete old log file if it exceeds kMaxLogFileSize of 25MiB

* update changelog

* bump version in pubspec.yaml

* update constants.dart

pkgs/unified_analytics/CHANGELOG.md

@@ -1,5 +1,6 @@
 ## 5.8.8+2
 
+- Avoid opening large telemetry log files to prevent out of memory errors.
 - Fixed bug where calling `Analytics.send` could result in a `FileSystemException` when unable to write to a log file.
 
 ## 5.8.8+1

pkgs/unified_analytics/lib/src/constants.dart

@@ -78,6 +78,11 @@ const String kGoogleAnalyticsMeasurementId = 'G-04BXPVBCWJ';
 /// How many data records to store in the log file.
 const int kLogFileLength = 2500;
 
+/// The maximum allowed size of the telemetry log file.
+///
+/// 25 MiB.
+const int kMaxLogFileSize = 25 * (1 << 20);
+
 /// Filename for the log file to persist sent events on user's machine.
 const String kLogFileName = 'dart-flutter-telemetry.log';
 

pkgs/unified_analytics/lib/src/log_handler.dart

@@ -282,10 +282,18 @@ class LogHandler {
  /// This will keep the max number of records limited to equal to
  /// or less than [kLogFileLength] records.
  void save({required Map<String, Object?> data}) {
- var records = logFile.readAsLinesSync();
- final content = '${jsonEncode(data)}\n';
-
  try {
+ final stat = logFile.statSync();
+ List<String> records;
+ if (stat.size > kMaxLogFileSize) {
+ logFile.deleteSync();
+ logFile.createSync();
+ records = [];
+ } else {
+ records = logFile.readAsLinesSync();
+ }
+ final content = '${jsonEncode(data)}\n';
+
  // When the record count is less than the max, add as normal;
  // else drop the oldest records until equal to max
  if (records.length < kLogFileLength) {

pkgs/unified_analytics/test/log_handler_test.dart

@@ -2,9 +2,12 @@
 // for details. 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:convert';
+
 import 'package:file/file.dart';
 import 'package:file/memory.dart';
 import 'package:path/path.dart' as p;
+import 'package:test/fake.dart';
 import 'package:test/test.dart';
 
 import 'package:unified_analytics/src/constants.dart';
@@ -221,6 +224,47 @@ void main() {
  logHandler.save(data: {});
  });
 
+ test('deletes log file larger than kMaxLogFileSize', () async {
+ var deletedLargeLogFile = false;
+ var wroteDataToLogFile = false;
+ const data = <String, Object?>{};
+ final logFile = _FakeFile('log.txt')
+ .._deleteSyncImpl = (() => deletedLargeLogFile = true)
+ .._createSyncImpl = () {}
+ .._statSyncImpl = (() => _FakeFileStat(kMaxLogFileSize + 1))
+ .._writeAsStringSync = (contents, {mode = FileMode.append}) {
+ expect(contents.trim(), data.toString());
+ expect(mode, FileMode.writeOnlyAppend);
+ wroteDataToLogFile = true;
+ };
+ final logHandler = LogHandler(logFile: logFile);
+
+ logHandler.save(data: data);
+ expect(deletedLargeLogFile, isTrue);
+ expect(wroteDataToLogFile, isTrue);
+ });
+
+ test('does not delete log file if smaller than kMaxLogFileSize', () async {
+ var wroteDataToLogFile = false;
+ const data = <String, Object?>{};
+ final logFile = _FakeFile('log.txt')
+ .._deleteSyncImpl =
+ (() => fail('called logFile.deleteSync() when file was less than '
+ 'kMaxLogFileSize'))
+ .._createSyncImpl = () {}
+ .._readAsLinesSyncImpl = (() => ['three', 'previous', 'lines'])
+ .._statSyncImpl = (() => _FakeFileStat(kMaxLogFileSize - 1))
+ .._writeAsStringSync = (contents, {mode = FileMode.append}) {
+ expect(contents.trim(), data.toString());
+ expect(mode, FileMode.writeOnlyAppend);
+ wroteDataToLogFile = true;
+ };
+ final logHandler = LogHandler(logFile: logFile);
+
+ logHandler.save(data: data);
+ expect(wroteDataToLogFile, isTrue);
+ });
+
  test('Catching cast errors for each log record silently', () async {
  // Write a json array to the log file which will cause
  // a cast error when parsing each line
@@ -301,3 +345,51 @@ void main() {
  expect(newString, testString);
  });
 }
+
+class _FakeFileStat extends Fake implements FileStat {
+ _FakeFileStat(this.size);
+
+ @override
+ final int size;
+}
+
+class _FakeFile extends Fake implements File {
+ _FakeFile(this.path);
+
+ List<String> Function()? _readAsLinesSyncImpl;
+
+ @override
+ List<String> readAsLinesSync({Encoding encoding = utf8}) =>
+ _readAsLinesSyncImpl!();
+
+ @override
+ final String path;
+
+ FileStat Function()? _statSyncImpl;
+
+ @override
+ FileStat statSync() => _statSyncImpl!();
+
+ void Function()? _deleteSyncImpl;
+
+ @override
+ void deleteSync({bool recursive = false}) => _deleteSyncImpl!();
+
+ void Function()? _createSyncImpl;
+
+ @override
+ void createSync({bool recursive = false, bool exclusive = false}) {
+ return _createSyncImpl!();
+ }
+
+ void Function(String contents, {FileMode mode})? _writeAsStringSync;
+
+ @override
+ void writeAsStringSync(
+ String contents, {
+ FileMode mode = FileMode.write,
+ Encoding encoding = utf8,
+ bool flush = false,
+ }) =>
+ _writeAsStringSync!(contents, mode: mode);
+}