如何使用 AWS SAM CLI 在本地执行 Step Function？

Question

我正在尝试弄清楚如何在不消耗 aws 资源的情况下为 AWS Step Functions 和运行整个工作流设置本地开发。

我已经使用“Step Functions Sample App (Stock Trader)”模板初始化了一个项目，该模板具有以下状态机图：

在这一点上，我已经设法通过运行一次只使用一个 lambda 函数来测试执行 sam local invoke StockCheckerFunction。

有什么方法可以在本地运行一次完成整个工作流程吗？

stock_trader.asl.json

{
    "Comment": "A state machine that does mock stock trading.",
    "StartAt": "Check Stock Value",
    "States": {
        "Check Stock Value": {
            "Type": "Task",
            "Resource": "${StockCheckerFunctionArn}",
            "Retry": [
                {
                    "ErrorEquals": [
                        "States.TaskFailed"
                    ],
                    "IntervalSeconds": 15,
                    "MaxAttempts": 5,
                    "BackoffRate": 1.5
                }
            ],
            "Next": "Buy or Sell?"
        },
        "Buy or Sell?": {
            "Type": "Choice",
            "Choices": [
                {
                    "Variable": "$.stock_price",
                    "NumericLessThanEquals": 50,
                    "Next": "Buy Stock"
                }
            ],
            "Default": "Sell Stock"
        },
        "Sell Stock": {
            "Type": "Task",
            "Resource": "${StockSellerFunctionArn}",
            "Retry": [
                {
                    "ErrorEquals": [
                        "States.TaskFailed"
                    ],
                    "IntervalSeconds": 2,
                    "MaxAttempts": 3,
                    "BackoffRate": 1
                }
            ],
            "Next": "Record Transaction"
        },
        "Buy Stock": {
            "Type": "Task",
            "Resource": "${StockBuyerFunctionArn}",
            "Retry": [
                {
                    "ErrorEquals": [
                        "States.TaskFailed"
                    ],
                    "IntervalSeconds": 2,
                    "MaxAttempts": 3,
                    "BackoffRate": 1
                }
            ],
            "Next": "Record Transaction"
        },
        "Record Transaction": {
            "Type": "Task",
            "Resource": "${DDBPutItem}",
            "Parameters": {
                "TableName": "${DDBTable}",
                "Item": {
                    "Id": {
                        "S.$": "$.id"
                    },
                    "Type": {
                        "S.$": "$.type"
                    },
                    "Price": {
                        "N.$": "$.price"
                    },
                    "Quantity": {
                        "N.$": "$.qty"
                    },
                    "Timestamp": {
                        "S.$": "$.timestamp"
                    }
                }
            },
            "Retry": [
                {
                    "ErrorEquals": [
                        "States.TaskFailed"
                    ],
                    "IntervalSeconds": 20,
                    "MaxAttempts": 5,
                    "BackoffRate": 10
                }
            ],
            "End": true
        }
    }
}

Answer 1

您需要在本地机器上安装 AWS Step Functions Local 和 AWS Lambda 运行，然后您可以测试状态机和 Lambda 函数，而无需将代码部署到 AWS。

按照以下步骤操作： https://docs.aws.amazon.com/step-functions/latest/dg/sfn-local-lambda.html

如何使用 AWS SAM CLI 在本地执行 Step Function？

How to use AWS SAM CLI to execute a Step Function locally?

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