【发布时间】：2021-06-29 13:07:30
【问题描述】：
我有一个使用 Java 实现的处理程序的 AWS Step Function。
我的步进函数定义：
definition:
Comment: Steps for issuing a card
StartAt: RecipientFraudChecks
States:
RecipientFraudChecks:
Type: Task
Next: SaveTaskToken
Resource: arn:aws:lambda:eu-west-1:099720403855:RecipientFraudChecks
SaveTaskToken:
Type: Task
Resource: arn:aws:lambda:eu-west-1:12345678:function:SaveTaskToken
End: true
我有一个 Java 项目，所有 Lambda 函数处理程序都在那里定义：
public class SaveTaskToken implements RequestHandler<Map<String,String>, String> {
....
@Override
public String handleRequest(Map<String, String> input, final Context context) {
// do the fraud checks
System.out.println("the context is: " + gson.toJson(context));
System.out.println("input: " + gson.toJson(input));
}
我正在使用 AWS SAM 在本地运行 step 函数，并根据此触发：https://docs.aws.amazon.com/step-functions/latest/dg/sfn-local-lambda.html#install-sam
在context 内，我希望看到任务令牌，但我没有。日志显示：
the context is: {
"memoryLimit": 512,
"awsRequestId": "5065a9aa-1a4a-46fe-9b58-7dc2194f92b7",
"logGroupName": "aws/lambda/SaveTaskToken",
"logStreamName": "$LATEST",
"functionName": "SaveTaskToken",
"functionVersion": "$LATEST",
"invokedFunctionArn": "",
"cognitoIdentity": {
"identityId": "",
"poolId": ""
},
"logger": {}
}
事实上，它与我所期望的全局上下文完全不同 in the docs。
我做错了什么？任务令牌如何获取？
编辑
我将Parameters 属性添加到“SaveTaskToken”并将资源更改为arn:aws:states:::lambda:invoke.waitForTaskToken，并且知道我可以获得任务令牌：
definition:
Comment: Steps for issuing a card
StartAt: RecipientFraudChecks
States:
RecipientFraudChecks:
Type: Task
Next: SaveTaskToken
Resource: arn:aws:lambda:eu-west-1:099720403855:RecipientFraudChecks
SaveTaskToken:
Type: Task
Resource: arn:aws:states:::lambda:invoke.waitForTaskToken
Parameters:
FunctionName: arn:aws:lambda:eu-west-1:12345678:function:SaveTaskToken
Payload:
taskToken
End: true
在日志中我可以看到：
the input is: {
"taskToken": "5286"
}
它导致了另一个问题 - 它覆盖了状态机的输入。我传入输入：
{"giftCode": "xxx"}
在第一个 Lambda 函数 RecipientFraudChecks 中，我可以获得输入。但是，在第二个中，自从添加了Parameters 属性后，我现在无法再获取状态机的输入，只能获取任务令牌...
编辑 已经在这里实现了答案：https://stackoverflow.com/a/66995869/1246159
{
"Comment": "Steps for issuing a card",
"StartAt": "RecipientFraudChecks",
"States": {
"RecipientFraudChecks": {
"Type": "Task",
"Next": "PauseCardIfNecessary",
"ResultPath": "$.firstLambdaOutput",
"Resource": "arn:aws:lambda:us-east-1:123456789012:function:RecipientFraudChecks"
},
"PauseCardIfNecessary": {
"Type": "Task",
"Next": "GetOrCreateClient",
"Resource": "arn:aws:states:::lambda:invoke.waitForTaskToken",
"Parameters": {
"FunctionName": "arn:aws:lambda:us-east-1:123456789012:function:PauseCardIfNecessary",
"Payload": {
"token.$": "$$.Task.Token",
"otherInput.$": "$"
}
}
},
"GetOrCreateClient": {
"Type": "Task",
"Next": "GetOrAccountClient",
"Resource": "arn:aws:lambda:us-east-1:123456789012:function:GetOrCreateClient"
},
"GetOrAccountClient": {
"Type": "Task",
"Resource": "arn:aws:lambda:us-east-1:123456789012:function:GetOrAccountClient",
"End": true
}
}
}
但我得到另一个错误，这里是日志：
arn: aws: states: eu-west-1: 123456789012: execution: HelloWorld5: cardIssue: {
"Type": "TaskStateExited",
"PreviousEventId": 5,
"StateExitedEventDetails": {
"Name": "RecipientFraudChecks",
"Output": "{\"inputToStep\":\"xxxx\",\"firstLambdaOutput\":\"output of recipient lambda\"}"
}
} arn: aws: states: eu-west-1: 123456789012: execution: HelloWorld5: cardIssue: {
"Type": "TaskStateEntered",
"PreviousEventId": 6,
"StateEnteredEventDetails": {
"Name": "PauseCardIfNecessary",
"Input": "{\"inputToStep\":\"xxxx\",\"firstLambdaOutput\":\"output of recipient lambda\"}"
}
} arn: aws: states: eu-west-1: 123456789012: execution: HelloWorld5: cardIssue: {
"Type": "ExecutionFailed",
"PreviousEventId": 7,
"ExecutionFailedEventDetails": {
"Error": "States.Runtime",
"Cause": "An error occurred while executing the state 'PauseCardIfNecessary' (entered at the event id #7). The value for the field 'token.$' must be a valid JSONPath expression"
}
}
【问题讨论】：
标签： java amazon-web-services aws-lambda aws-step-functions