Follow a stream of live events — Kinesis Data Streams

Your goal

Write a live-event record and read its bytes from a stream shard.

Why this matters

A stream stores a sequence of events that consumers can read from a chosen position. You will write recognizable bytes, request a shard iterator, and retrieve the event you sent.

Words you will use

A stream is a continuing sequence of records. A partition key groups related data. A consumer reads records. A checkpoint records how far a consumer has processed.

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 one-shard stream

Create a Kinesis stream and wait until its API state is ACTIVE. A shard is a unit that holds an ordered sequence of records. This small stream has just one.

2. Write your event

Send your message as bytes with player-1 as its partition key. The response includes a sequence number. Related records use a stable partition key when their ordering matters.

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

3. Read from the shard

Request an iterator from the beginning and retrieve records. Decode their bytes and compare them with your message. This checks a real emulated write/read cycle.

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.