Want to Master Serverless Step Functions? Here’s a Simple Workflow to Get You Started

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You Should Know:

To implement the serverless image processing workflow using AWS Step Functions, follow these steps and commands:

  1. Create a Lambda Function to Trigger the Workflow:

– Use the AWS CLI to create a Lambda function:

aws lambda create-function --function-name ImageProcessingTrigger \
--runtime python3.8 --role arn:aws:iam::123456789012:role/lambda-execution-role \
--handler lambda_function.lambda_handler --zip-file fileb://function.zip

– The Lambda function should identify the file type and trigger the Step Function if the file is a .jpg.

2. Define the Step Function:

  • Create a JSON definition for the Step Function:
    {
    "Comment": "Image Processing Workflow",
    "StartAt": "ProcessImage",
    "States": {
    "ProcessImage": {
    "Type": "Parallel",
    "End": true,
    "Branches": [
    {
    "StartAt": "CopyImage",
    "States": {
    "CopyImage": {
    "Type": "Task",
    "Resource": "arn:aws:lambda:us-east-1:123456789012:function:CopyImageFunction",
    "End": true
    }
    }
    },
    {
    "StartAt": "ResizeImage",
    "States": {
    "ResizeImage": {
    "Type": "Task",
    "Resource": "arn:aws:lambda:us-east-1:123456789012:function:ResizeImageFunction",
    "End": true
    }
    }
    }
    ]
    }
    }
    }
    
  • Use the AWS CLI to create the Step Function:
    aws stepfunctions create-state-machine --name ImageProcessingWorkflow \
    --definition file://workflow-definition.json --role-arn arn:aws:iam::123456789012:role/stepfunctions-execution-role
    

3. Save Metadata to DynamoDB: