Prologue: The Ultimate Logging Utility for Efficient Debugging
Published: 2023-08-12 14:01:36

Introducing the Prologue logging utility for [TS](https://gist.github.com/EricEisaman/7bced89352c7a0b7ae6c6d1e6bf962e3) and [JS](https://gist.github.com/EricEisaman/eae2a0d62869d3c11650b9dbfe76b5a7)! 🎉 This powerful tool enhances the browser window's console.log, console.warn, and console.error functions, enabling developers to filter logs based on tags specified in the URL. With Prologue, the debugging experience is elevated, and log analysis becomes more efficient. Let's explore how to utilize this utility effectively:

1. **Instantiating Prologue**: Begin by instantiating the Prologue class in your project. This step involves creating a new instance of the Prologue class, which automatically patches the console functions. This enables Prologue to intercept and modify the logging behavior.

2. **Filtering Logs with Tags**: Prologue empowers you to filter logs based on tags specified in the URL. To activate log filtering, append desired tags as a query parameter named "logs" to the URL. For example, adding "?logs=mycomponent" filters logs with the "mycomponent" tag. Multiple tags can be specified by separating them with a hyphen, such as "?logs=mycomponent-debug". To log everything, simply add "?logs" to the URL without specifying any tags. Logs via console.warn are filtered by default. You can see warnings with ?logs=warn. Error logs via console.error are always shown.

3. **Logging with User-Specified Tags**: In addition to URL-based filtering, Prologue allows you to log messages with user-specified tags. To log a message with a specific tag, use the following syntax: `console.log("^^tag^^", "Your log message")`. Replace "tag" with your desired custom tag. This feature enables categorization and differentiation of logs based on your specific needs.

4. **Logging with Modified Console Functions**: Once Prologue is instantiated and tags are specified, start logging using the modified console functions. The console.log, console.warn, and console.error functions now check if logs should be displayed based on the filtering criteria or user-specified tags. If the log meets the criteria, the original console function is called with the same arguments.

5. **Analyzing Filtered Logs**: Prologue enables focused analysis of filtered logs that match the specified tags. This capability allows developers to concentrate on specific types of logs and easily identify relevant information. By streamlining the debugging process through tag-based filtering, issues can be swiftly identified and addressed.

6. **Testing and Verification**: Thoroughly test Prologue with various scenarios and edge cases to ensure its correct functionality. Verify that the console.log, console.warn, and console.error functions behave as expected with Prologue enabled. This rigorous testing ensures reliable and efficient logging and debugging processes.

By following these steps, you can effectively leverage the Prologue logging utility to enhance your debugging experience. The ability to filter logs based on tags, including user-specified tags, provides a powerful tool for analyzing and addressing issues in your code. Play with Prologue at [Glitch](https://prologue-util.glitch.me/). Happy debugging! 🚀