AWS Step Functions Example

Step 1: Set Up a State Machine

We'll create a state machine that handles image processing. When an image is uploaded to Amazon S3, this workflow will trigger and perform two tasks: resizing the image and applying a filter.

Step 2: Define States

1. UploadImage: This state represents the initial step, triggered when an image is uploaded to S3. It receives input data, including the image file's location.

2. ResizeImage: After the image is uploaded, the workflow moves to this state. It resizes the image to a predefined size.

3. ApplyFilter: The final state applies a filter to the resized image.

Step 3: Create the State Machine Definition

Here's a simplified JSON definition of our state machine:

{
  "StartAt": "UploadImage",
  "States": {
    "UploadImage": {
      "Type": "Task",
      "Resource": "arn:aws:lambda:REGION:ACCOUNT_ID:function:UploadImageFunction",
      "End": true
    },
    "ResizeImage": {
      "Type": "Task",
      "Resource": "arn:aws:lambda:REGION:ACCOUNT_ID:function:ResizeImageFunction",
      "End": true
    },
    "ApplyFilter": {
      "Type": "Task",
      "Resource": "arn:aws:lambda:REGION:ACCOUNT_ID:function:ApplyFilterFunction",
      "End": true
    }
  }
}

 

Step 4: Run the State Machine

Once the state machine is defined, you can create an execution. This execution will process the image based on the defined states and transitions.

Step 5: Monitor and Debug

AWS Step Functions offers detailed logging and visual representations of your workflow executions, making it easy to monitor and debug any issues.