10 Android Logging Best Practices

Android logging is a process of recording certain events that happen during the execution of an Android application. Logging is an important tool for developers to debug and troubleshoot their code.

There are different levels of logging, and each has its own purpose. In this article, we will discuss 10 Android logging best practices that every Android developer should follow.

1. Use the Log class

The Log class provides a number of methods that can be used to log messages. These include:

-v() for verbose logging
-d() for debug logging
-i() for informational logging
-w() for warning logging
-e() for error logging

Each of these methods takes two parameters:

-A tag string that can be used to identify the source of the log message
-A message string that contains the log message

The Log class also provides a static method, isLoggable(), which can be used to determine if a given tag and log level are enabled. This is important because calling one of the logging methods (for example, e()) can be expensive if the message will not be logged.

2. Don’t log in production builds

When you log in a production build, it’s easy to accidentally leak sensitive information. For example, you might accidentally log a password or an API key. Or, you might log something that could be used to exploit a security vulnerability.

Even if you’re careful about what you log, there’s always the possibility that something will slip through the cracks. So, it’s best to err on the side of caution and not log in production builds.

If you need to log in a production build for debugging purposes, make sure to remove all logging code before shipping the build to customers.

3. Avoid logging sensitive information

When logging information to the Android system log, it is stored in a public location that can be accessed by any app on the device. As a result, if an attacker were able to get access to a device, they could potentially extract sensitive information from the logs.

To avoid this, it is important to ensure that any sensitive information is not logged. This includes things like passwords, credit card numbers, and other personal information.

If you do need to log sensitive information, there are ways to do so securely. One option is to use a tool like ProGuard to obfuscate the information in the logs. Another option is to encrypt the information before logging it.

4. Use a custom tag for your application

When you use the Android logging system, the log messages are tagged with the default tag for your application. The default tag is usually the name of your application’s package.

Using the default tag has a few disadvantages. First, it’s not very informative. All you see is the package name, and you have no idea what part of the code generated the log message. Second, it’s not very unique. If you have multiple applications on your device, they all use the same default tag. So if you’re looking at the logs for one application, you might see log messages from another application that just happen to have the same package name.

To avoid these problems, you should use a custom tag for your application. A custom tag is more informative than the default tag, and it’s also more unique. So if you’re looking at the logs for one application, you won’t see log messages from another application that just happen to have the same package name.

To set a custom tag for your application, you can use the setTag() method in the Log class. For example, you could use the following code to set a custom tag for your application:

Log.setTag(“MyApp”);

Now when you generate log messages, they will be tagged with “MyApp” instead of the default package name.

5. Keep logs short and simple

When troubleshooting an issue, it can be helpful to have as much information as possible. However, when reviewing a large number of logs, it can be difficult to find the relevant information if the logs are too verbose.

It’s important to strike a balance between providing enough information to be useful while also keeping the logs concise. For example, rather than logging every single step in a process, you might want to log only the start and end of the process.

Additionally, it can be helpful to use different levels of logging depending on the severity of the issue. For example, you might want to use a debug level for issues that are not critical and a warning level for issues that are more serious.

By following these Android logging best practices, you can help ensure that your logs are both informative and easy to review.

6. Be consistent with your tags

If you’re not consistent with your tags, it will be difficult to search for and find the logs you need when you’re trying to debug an issue. When you have hundreds or even thousands of log statements in your code, it can be daunting to try to figure out which ones are relevant to the issue you’re trying to debug.

Being consistent with your tags will help you narrow down the search and quickly find the logs you need. It’s also a good idea to use descriptive tags so that you can easily understand what each log is for.

Here are some tips for being consistent with your tags:

– Use the same tag for all log statements in a given class
– Use different tags for different classes
– Use a naming convention for your tags
– Use a tool to help manage your tags

7. Know when to use each type of log method

Verbose should be used for the most detailed logging, usually for debugging purposes.

Debug should be used for debug builds and can be used for less important logs that might still be useful when debugging.

Info should be used for informational messages that are not errors.

Warn should be used for potential errors that are not yet causing problems.

Error should be used for actual errors that are causing problems.

Assert should be used for conditions that should never happen and indicate a programming error.

8. Add context to your logs

If you’ve ever had to debug a problem in your code, you know how frustrating it can be to try and piece together what’s going on based on a bunch of log messages that don’t give you any context. It’s like trying to put together a puzzle without knowing what the final picture is supposed to look like.

Adding context to your logs means adding information that will help you understand the message in the context of the overall system. For example, if you’re logging an error, include information about the state of the system when the error occurred. This might include information about the user that was logged in, the data that was being processed, or anything else that would be relevant to understanding the error.

By adding this context, you’ll be able to more quickly and easily identify problems when they occur, and you’ll be less likely to miss important details that could help you solve the problem.

9. Use an external logger library

When you’re using the Android logging system, all of your logs are stored in a circular buffer. This means that if your app crashes, you’ll only be able to see the logs that were generated in the few seconds before the crash.

However, when you use an external logger library, your logs are stored in a file on the device. This means that even if your app crashes, you’ll still be able to see all of the logs that were generated leading up to the crash.

There are many different logger libraries available for Android, so you’ll need to choose one that’s right for your project. Some popular options include Timber, Log4j, and slf4j.

10. Do not ignore exceptions

Exceptions are important because they indicate that something went wrong in your code. They can be caused by programming errors, but they can also be caused by conditions that are not under your control, such as an unavailable network resource.

Ignoring exceptions is dangerous because it means that you will never know about the problem, and it might cause your app to crash or behave in unexpected ways.

Instead of ignoring exceptions, log them and add handling code so that your app can recover gracefully from the error.