Find the useful clues in application logs — CloudWatch Logs

Your goal

Write an application log message and retrieve it from its stream.

Why this matters

A useful log message should be retrievable from the place where an app sent it. You will create a group and stream, write a timestamped event, and read your exact message back.

Words you will use

A log event records something that happened. A log group organizes related logs. A request ID connects events from one request. Retention controls how long logs are kept.

How to proceed

Start a fresh emulator, read each numbered step, and enter the practice settings shown. Run the action, inspect its API receipt, then continue. Finish lab checks the emulator state again before saving your progress.

1. Create a log group and stream

Create a log group for the app and a stream called practice. A group holds related streams; a stream is a sequence of log events. Use harmless training data only.

2. Write a recognizable event

Send your message with the current timestamp. A useful log explains what happened without leaking passwords or personal details. The message here is entirely your invented practice text.

Practice message: Type a short message that you can recognize in the API result. Suggested practice value: Hello from my lab.

3. Read the stored log event

Get events from the beginning of the stream and find your exact message. This checks stored log data instead of simply echoing the form input.

Practice, then check your understanding

Perform the actions yourself and inspect the returned state. Errors keep your settings so you can retry. Starting another lab clears the previous live environment. Earned XP is kept, and signed-in achievements sync to your account. Replay does not award duplicate XP.

Read the official AWS documentation for service behavior and production details.