react-native-xlog

Wechat's Xlog framework for RN.

You can send log to Xlog, and manager Xlog lifecycle. Handle js/native crash log in production builds.

attention: you will see the crash log only when you restart your app

Feature

• iOS: send log to xlog for js function
• iOS: RCTLog output to xlog
• iOS: crash message output to xlog
• android: send log to xlog for js function
• android: RCTLog output to xlog
• android: crash message output in the xlog

Get Start

Add it to your project

1. Run npm i -S react-native-xlog
2. Add Xlog to you project.

Linking iOS

run react-native link react-native-xlog to link the library.

if Header Search Paths does not have the $(SRCROOT)/../node_modules/react-native/React + recursive, linking may fail.

Android

1. config gradle script

• add dependency in android/app/build.gradle

dependencies {
    compile fileTree(dir: "libs", include: ["*.jar"])
    compile "com.android.support:appcompat-v7:23.0.1"
    compile "com.facebook.react:react-native:+"  // From node_modules
    compile "com.tencent.mars:mars-xlog:1.0.4" //<--add here
    compile project(":react-native-xlog") //<--add here
}

• add react-native-xlog project in root project's settings.gradle

include ':react-native-xlog'
project(':react-native-xlog').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-xlog/android')

• add variables in root project's build.gradle

ext {
    MARS_XLOG_VERSION_NAME='1.0.4'
    MARS_XLOG_VERSION_NAME_SUFFIX = ''
}

2. add XLogPackage

...
import com.engsshi.xlog.XLogPackage;
...

public class MainApplication extends Application implements ReactApplication {
    ...
    private final ReactNativeHost mReactNativeHost = new ReactNativeHost(this) {
        @Override
        protected boolean getUseDeveloperSupport() {
            return BuildConfig.DEBUG;
        }

        @Override
        protected List<ReactPackage> getPackages() {
            return Arrays.asList(
                    new MainReactPackage(),
                    new XLogPackage()  // <--add here
            );
        }
    };
   ...
}   

2. init xlog settings.
   JS has to exception type: fatal exception(just throw JavascriptException in native) and soft exception(use FLog.e in native). you can find this from RN source file: ExceptionsManagerModule.java and support you two init way:

• XLogModule.init(xLogSetting): normal log, include FLog
• XLogModule.initWithNativeCrashInclude(xLogSetting, this): normal log and crash log (JS fatal exception and native uncaught exception)

...
import android.os.Environment;
import com.engsshi.xlog.XLogModule;
import com.engsshi.xlog.XLogSetting;
...

public class MainApplication extends Application implements ReactApplication {
  ...
   @Override
    public void onCreate() {
        super.onCreate();
        ...
        final String appName = this.getString(R.string.app_name);
        final String logPath = Environment.getExternalStorageDirectory().getAbsolutePath() + '/' + appName + "/log";

        XLogSetting xLogSetting = XLogSetting.builder()
                .setLevel(XLogSetting.LEVEL_DEBUG)
                .setPath(logPath)
                .setCacheDir("")
                .setAppenderMode(XLogSetting.APPENDER_MODE_ASYNC)
                .setNamePrefix(appName)
                .setOpenConsoleLog(true)
                .build();
        XLogModule.init(xLogSetting)
        //XLogModule.initWithNativeCrashInclude(xLogSetting, this);
        ...
  }
  ...
}

3. if your want to log early, rather than delay to RNView render done, your can turn on xlog early, just add in Application's onCreate() after XLogModule init done.

public class MainApplication extends Application implements ReactApplication {
  ...
   @Override
    public void onCreate() {
       // xlog init here ....
        ...
        XLogModule.open(); //optional, for this, you can log before into RNView 
        ...
  }
  ...
}

Usage

import Xlog from 'react-native-xlog';

Xlog.verbose('tag', 'log');
Xlog.debug('tag', 'log');
Xlog.info('tag', 'log');
Xlog.warn('tag', 'log');
Xlog.error('tag', 'log');
Xlog.fatal('tag', 'log');

Decode log file

Use this script to decode log file:

• myapp.mmap2
• myapp_20170723.xlog

python decode_mars_log_file.py ~/Downloads/log/myapp_20170723.xlog