Logging - React Native SDK

Set or Change the Realm Log Level

You can set the level of detail reported by the Realm React Native SDK. To configure the log level, pass a valid level string value to setLogLevel():

• "all"

• "trace"

• "debug"

• "detail"

• "info"

• "warn"

• "error"

• "fatal"

• "off"

Realm.setLogLevel('trace');

Use setLogLevel() anywhere in your app to increase or decrease log verbosity at different points in your code. This behavior differs from the deprecated sync client log level, which had to be set before opening a synced realm and could not be changed.

To turn off logging, pass "off" to setLogLevel():

Realm.setLogLevel('off');

Customize the Logger

To set a custom logger, call setLogger(). This method recieves level and message arguments from the Realm logger, not individual realms. Use these arguments to define your own logging behavior.

You must use setLogger() before you open a realm with RealmProvider. You can't use setLogger() in a hook in the same component as RealmProvider because RealmProvider opens a realm when it is mounted. Hooks generally run after a component is mounted, which means RealmProvider already opened a realm.

Most of the time, you should set your custom logger outside of the React tree. For example, in your app's root index.js file.

Realm.setLogger((level, message) => {
  const log = {
    message,
    level,
  };
  setLogs(previousLogs => [...previousLogs, log]);
});

This sets the logging behavior for all Realm logging in your application, regardless of where you set it. If you do not provide a log level, the default is "info".