Logger组件之日志序列化

[soapgu]

• 引言

一直一来Logger组件我们都是使用默认的AndroidLogAdapter，就是之间打Logcat日志。比较好用。所以一直一来也没有进一步深入的需求，直到现在为了测试安卓的稳定性，使用长期监控的程序运行情况。光使用Logcat感觉有点不太保险，第一主要Logcat本身会定时清理，一些久远的日志难以持久，第二Logcat本身其他日志量也很大，虽然有命令可以过滤，但是也不是特别方便。不过保存到本机来的安心

• 持有化日志的使用

废话不多说了。先直接看官挡说明

Save logs to the file

//TODO: More information will be added later

Logger.addLogAdapter(new DiskLogAdapter());

Add custom tag to Csv format strategy

FormatStrategy formatStrategy = CsvFormatStrategy.newBuilder()
  .tag("custom")
  .build();
  
Logger.addLogAdapter(new DiskLogAdapter(formatStrategy));

这文档写的真是拉垮，聊了几句，连起码日志存哪里都不说清楚，无力吐槽。

无奈，只能翻代码
发现所有的日志都会输出到/sdcard/logger/logs_{n}.csv里面。
虽然勉强能用，但是显然不能满足要求。感觉这个SDK就是一个半成品。

• 自定义LogStrategy

本来想要直接重写WriteHandler，无奈相关代码是内部类。只能另起炉灶。

public class MyDiskLogStrategy extends DiskLogStrategy {
    public MyDiskLogStrategy(@NonNull Handler handler) {
        super(handler);
    }

    @SuppressLint("SimpleDateFormat")
    static class WriteHandler extends Handler {

        @NonNull private final String folder;
        private final int maxFileSize;
        private final DateFormat format = new SimpleDateFormat("yyyy-MM-dd");

        WriteHandler(@NonNull Looper looper, @NonNull String folder, int maxFileSize  ) {
            super(looper);
            this.folder = folder;
            this.maxFileSize = maxFileSize;
        }

        @SuppressWarnings("checkstyle:emptyblock")
        @Override public void handleMessage(@NonNull Message msg) {
            String content = (String) msg.obj;

            FileWriter fileWriter = null;
            String fileName = format.format(new Date());
            File logFile = getLogFile(folder, fileName);

            try {
                fileWriter = new FileWriter(logFile, true);

                writeLog(fileWriter, content);

                fileWriter.flush();
                fileWriter.close();
            } catch (IOException e) {
                if (fileWriter != null) {
                    try {
                        fileWriter.flush();
                        fileWriter.close();
                    } catch (IOException e1) { /* fail silently */ }
                }
            }
        }

        /**
         * This is always called on a single background thread.
         * Implementing classes must ONLY write to the fileWriter and nothing more.
         * The abstract class takes care of everything else including close the stream and catching IOException
         *
         * @param fileWriter an instance of FileWriter already initialised to the correct file
         */
        private void writeLog(@NonNull FileWriter fileWriter, @NonNull String content) throws IOException {

            fileWriter.append(content);
        }

        private File getLogFile(@NonNull String folderName, @NonNull String fileName) {

            File folder = new File(folderName);
            if (!folder.exists()) {
                folder.mkdirs();
            }

            int newFileCount = 0;
            File newFile;
            File existingFile = null;

            newFile = new File(folder, String.format("%s_%s.csv", fileName, newFileCount));
            while (newFile.exists()) {
                existingFile = newFile;
                newFileCount++;
                newFile = new File(folder, String.format("%s_%s.csv", fileName, newFileCount));
            }

            if (existingFile != null) {
                if (existingFile.length() >= maxFileSize) {
                    return newFile;
                }
                return existingFile;
            }

            return newFile;
        }
    }
}

把DiskLogStrategy 的主要源码搬过来，把文件名改为按天记录日志
String fileName = format.format(new Date());
接下来是调用部分

 String diskPath = Environment.getExternalStorageDirectory().getAbsolutePath();
        String folder = diskPath + File.separatorChar + "logger" + File.separatorChar + this.getPackageName();

        HandlerThread ht = new HandlerThread("AndroidFileLogger." + folder);
        ht.start();
        Handler handler = new MyDiskLogStrategy.WriteHandler(ht.getLooper(), folder, MAX_BYTES);
        LogStrategy logStrategy = new DiskLogStrategy(handler);
        FormatStrategy cvsFormatStrategy = CsvFormatStrategy.newBuilder()
                .tag(this.provideTagName())
                .logStrategy( logStrategy )
                .build();
        Logger.addLogAdapter( new DiskLogAdapter(cvsFormatStrategy) );

把日志目录设为/sdcard/logger/{package}/,这样通用过，还不会冲突。

• 总结

最终效果

这才是我想要的。

相关链接

• logger文档