借助 AWS Step Functions 将回调 URL 用于批准电子邮件

import json, os, boto3def lambda_handler(event, context):    print('Event:', json.dumps(event))    # Switch between the two blocks of code to run    # This is normally in separate functions    if event['step'] == 'SendApprovalRequest':        print('Calling sfn-callback-urls app')        input = {            # Step Functions gives us this callback token            # sfn-callback-urls needs it to be able to complete the task            "token": event['token'],            "actions": [                # The approval action that transfers the name to the output                {                    "name": "approve",                    "type": "success",                    "output": {                        # watch for re-use of this field below                        "name_in_output": event['name_in_input']                    }                },                # The rejection action that names the rejecter                {                    "name": "reject",                    "type": "failure",                    "error": "rejected",                    "cause": event['name_in_input'] + " rejected it"                }            ]        }        response = boto3.client('lambda').invoke(            FunctionName=os.environ['CREATE_URLS_FUNCTION'],            Payload=json.dumps(input)        )        urls = json.loads(response['Payload'].read())['urls']        print('Got urls:', urls)
        # Compose email        email_subject = 'Step Functions example approval request'
        email_body = """Hello {name},        Click below (these could be better in HTML emails):
        Approve:        {approve}
        Reject:        {reject}        """.format(            name=event['name_in_input'],            approve=urls['approve'],            reject=urls['reject']        )    elif event['step'] == 'SendConfirmation':        # Compose email        email_subject = 'Step Functions example complete'
        if 'Error' in event['output']:            email_body = """Hello,            Your task was rejected: {cause}            """.format(                cause=event['output']['Cause']            )        else:            email_body = """Hello {name},            Your task is complete.            """.format(                name=event['output']['name_in_output']            )    else:        raise ValueError
    print('Sending email:', email_body)    boto3.client('sns').publish(        TopicArn=os.environ['TOPIC_ARN'],        Subject=email_subject,        Message=email_body    )    print('done')    return {}

{    "Version": "1.0",    "StartAt": "SendApprovalRequest",    "States": {        "SendApprovalRequest": {            "Type": "Task",            "Resource": "arn:aws:states:::lambda:invoke.waitForTaskToken",            "Parameters": {                "FunctionName": "ApprovalEmailsFunction",                "Payload": {                    "step.$": "$$.State.Name",                    "name_in_input.$": "$.name",                    "token.$": "$$.Task.Token"                }            },            "ResultPath": "$.output",            "Next": "SendConfirmation",            "Catch": [                {                    "ErrorEquals": [ "rejected" ],                    "ResultPath": "$.output",                    "Next": "SendConfirmation"                }            ]        },        "SendConfirmation": {            "Type": "Task",            "Resource": "arn:aws:states:::lambda:invoke",            "Parameters": {                "FunctionName": "ApprovalEmailsFunction",                "Payload": {                    "step.$": "$$.State.Name",                    "output.$": "$.output"                }            },            "End": true        }    }}

{  "name": "Ben"}