Flutter日志管理插件dragon_logs的使用

Flutter日志管理插件dragon_logs的使用

安装

首先，你需要在 pubspec.yaml 文件中添加依赖项：

dependencies:
  dragon_logs: ^1.0.4

然后运行以下命令来安装依赖项：

flutter pub get

初始化

初始化日志记录器。这个方法用于准备日志记录器并确保任何超出设置的最大存储大小的日志都被删除。

await DragonLogs.init();

设置会话元数据

设置与日志相关的会话元数据。这可以是用户ID、设备信息等。

DragonLogs.setSessionMetadata({
  'userID': '12345',
  'device': 'Pixel 4a',
  'appVersion': '1.0.0'
});

清除会话元数据

清除之前设置的会话元数据。

DragonLogs.clearSessionMetadata();

记录日志

记录一条消息，并可选地附带一个键。

log('This is a sample log message.');
log('User logged in', 'USER_ACTION');

导出日志

获取所有存储的日志作为流。

final logsStream = DragonLogs.exportLogsStream();

File file = File('${getApplicationCacheDirectory}/output.txt');

file = await file.exists() ? file : await file.create(recursive: true);

final logFileSink = file.openWrite(mode: FileMode.append);

for (final log in await logsStream) {
  logFileSink.writeln(log);
}

await logFileSink.close();

获取所有存储的日志作为单个字符串。

final logsString = await DragonLogs.exportLogsString();
print(logsString);

将日志导出到下载文件。

await DragonLogs.exportLogsToDownload();

获取日志文件夹大小

获取日志存储文件夹的当前大小（以字节为单位）。

final sizeInBytes = await DragonLogs.getLogFolderSize();
print('Log folder size: $sizeInBytes bytes');

性能指标摘要

获取日志记录器的性能指标摘要（即将推出）。

final metricsSummary = DragonLogs.performanceMetricsSummary;
print(metricsSummary);

示例代码

下面是一个完整的示例代码，展示了如何使用 dragon_logs 插件进行日志记录和处理。

import 'package:flutter/material.dart';
import 'package:dragon_logs/dragon_logs.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await DragonLogs.init();
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  [@override](/user/override)
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: LogDemoPage(),
    );
  }
}

class LogDemoPage extends StatefulWidget {
  const LogDemoPage({super.key});

  [@override](/user/override)
  State<LogDemoPage> createState() => _LogDemoPageState();
}

class _LogDemoPageState extends State<LogDemoPage> {
  late final Timer periodicMetricsTimer;
  bool isLoading = false;

  static const int itemCount = 10 * 1000;

  [@override](/user/override)
  void initState() {
    super.initState();
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Stored logs demo'),
        backgroundColor: isLoading ? Colors.purple : null,
        leading: isLoading
            ? Container(
                width: 32,
                height: 32,
                alignment: Alignment.center,
                child: const CircularProgressIndicator(),
              )
            : null,
      ),
      body: Column(
        children: [
          Wrap(
            spacing: 8,
            children: [
              ElevatedButton(
                onPressed: () {
                  setState(() =&gt; isLoading = true);

                  for (var i = 0; i &lt; itemCount; i++) {
                    log('${('$i')} This is a log');
                  }

                  ScaffoldMessenger.of(context)
                    ..clearSnackBars()
                    ..showSnackBar(
                      const SnackBar(
                        content: Text(
                          'Logged 10k items',
                        ),
                      ),
                    );

                  setState(() =&gt; isLoading = false);
                },
                child: const Text('Log 10k items'),
              ),
              ElevatedButton(
                onPressed: () async {
                  setState(() {
                    isLoading = true;
                  });
                  final stopWatch = Stopwatch()..start();

                  // ignore: unused_local_variable
                  final string = await DragonLogs.exportLogsStream()
                      .asyncMap((event) =&gt; event)
                      .join();

                  stopWatch.stop();

                  final size = await DragonLogs.getLogFolderSize();

                  final message =
                      'Read logs in ${stopWatch.elapsedMilliseconds}ms. '
                      'Log size: ${size ~/ 1024} KB';

                  ScaffoldMessenger.of(context)
                    ..clearSnackBars()
                    ..showSnackBar(
                      SnackBar(content: Text(message)),
                    );

                  setState(() {
                    isLoading = false;
                  });
                },
                child: const Text('Read logs'),
              ),

              // Button to download logs
              ElevatedButton(
                onPressed: () async {
                  setState(() =&gt; isLoading = true);

                  await DragonLogs.exportLogsToDownload();

                  final size = await DragonLogs.getLogFolderSize();

                  final message = 'Downloaded logs in {unknown} ms. '
                      'Log size: ${size ~/ 1024} KB';

                  ScaffoldMessenger.of(context)
                    ..clearSnackBars()
                    ..showSnackBar(
                      SnackBar(content: Text(message)),
                    );

                  setState(() {
                    isLoading = false;
                  });
                },
                child: const Text('Download logs'),
              ),
            ],
          ),
        ],
      ),
    );
  }

  [@override](/user/override)
  void dispose() {
    periodicMetricsTimer.cancel();
    super.dispose();
  }
}