在執行每個 map 迭代后從 AWS 步驟 function 獲得響應

Question

我有一個用例，其中用戶定義了一個工作流。 當用戶點擊 API 時，步驟 function 開始。 lambda 返回基於用戶的步驟列表並啟動工作流，例如：

步驟1。 它處理（提取）文檔，
第2步。 向數據庫插入一些數據

第三步。 .....

第4步。 .....

這里的步驟在 map 中，因為這些步驟是從 lambda 返回的。是否有任何方法可以從每次 map 迭代中獲得響應，以便我可以向用戶顯示流程在哪一步，以及上一步的 output。

這是我的步驟 function 設計：

test-fetch-input-workflow ：返回一個數組：[step1, step2, ....]

workflow step-lambda ：根據步驟名稱調用一些 lambda

Answer 1

假設您使用的是標准工作流程，您可以使用 GetExecutionHistory API 操作獲取此信息： https://docs.aws.amazon.com/step-functions/latest/apireference/API_GetExecutionHistory.html

您需要查找 MapIterationSucceeded 類型的事件，獲取 previousEventId，然后在具有該 ID 的 HistoryEvent 中查找 output。

例如，如果您有這樣一台 state 機器：

{    
"StartAt": "Generate Array for Map",
"States": {
  "Generate Array for Map": {
    "Type": "Pass",
    "Next": "Map",
    "Result": [
      1,
      2,
      3,
      4,
      5
    ]
  },
  "Map": {
    "Type": "Map",
    "ItemProcessor": {
      "ProcessorConfig": {
        "Mode": "INLINE"
      },
      "StartAt": "Generate Random Number",
      "States": {
        "Generate Random Number": {
          "Type": "Pass",
          "End": true,
          "Parameters": {
            "Random Number.$": "States.MathRandom(1,1000)"
          }
        }
      }
    },
    "End": true
  }
}

}

您的執行歷史將如下所示：

{
"events": [
    {
        "timestamp": "2022-12-08T16:44:07.651000-08:00",
        "type": "ExecutionStarted",
        "id": 1,
        "previousEventId": 0,
        "executionStartedEventDetails": {
            "input": "{\n    \"Comment\": \"Insert your JSON here\"\n}",
            "inputDetails": {
                "truncated": false
            },
            "roleArn": "arn:aws:iam::000000000000:role/service-role/StepFunctions-MapTest-role-613230dd"
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateEntered",
        "id": 2,
        "previousEventId": 0,
        "stateEnteredEventDetails": {
            "name": "Generate Array for Map",
            "input": "{\n    \"Comment\": \"Insert your JSON here\"\n}",
            "inputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateExited",
        "id": 3,
        "previousEventId": 2,
        "stateExitedEventDetails": {
            "name": "Generate Array for Map",
            "output": "[1,2,3,4,5]",
            "outputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapStateEntered",
        "id": 4,
        "previousEventId": 3,
        "stateEnteredEventDetails": {
            "name": "Map",
            "input": "[1,2,3,4,5]",
            "inputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapStateStarted",
        "id": 5,
        "previousEventId": 4,
        "mapStateStartedEventDetails": {
            "length": 5
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationStarted",
        "id": 6,
        "previousEventId": 5,
        "mapIterationStartedEventDetails": {
            "name": "Map",
            "index": 0
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationStarted",
        "id": 7,
        "previousEventId": 5,
        "mapIterationStartedEventDetails": {
            "name": "Map",
            "index": 1
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationStarted",
        "id": 8,
        "previousEventId": 5,
        "mapIterationStartedEventDetails": {
            "name": "Map",
            "index": 2
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationStarted",
        "id": 9,
        "previousEventId": 5,
        "mapIterationStartedEventDetails": {
            "name": "Map",
            "index": 3
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationStarted",
        "id": 10,
        "previousEventId": 5,
        "mapIterationStartedEventDetails": {
            "name": "Map",
            "index": 4
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateEntered",
        "id": 11,
        "previousEventId": 6,
        "stateEnteredEventDetails": {
            "name": "Generate Random Number",
            "input": "1",
            "inputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateExited",
        "id": 12,
        "previousEventId": 11,
        "stateExitedEventDetails": {
            "name": "Generate Random Number",
            "output": "{\"Random Number\":259}",
            "outputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationSucceeded",
        "id": 13,
        "previousEventId": 12,
        "mapIterationSucceededEventDetails": {
            "name": "Map",
            "index": 0
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateEntered",
        "id": 14,
        "previousEventId": 7,
        "stateEnteredEventDetails": {
            "name": "Generate Random Number",
            "input": "2",
            "inputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateExited",
        "id": 15,
        "previousEventId": 14,
        "stateExitedEventDetails": {
            "name": "Generate Random Number",
            "output": "{\"Random Number\":776}",
            "outputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationSucceeded",
        "id": 16,
        "previousEventId": 15,
        "mapIterationSucceededEventDetails": {
            "name": "Map",
            "index": 1
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateEntered",
        "id": 17,
        "previousEventId": 8,
        "stateEnteredEventDetails": {
            "name": "Generate Random Number",
            "input": "3",
            "inputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateExited",
        "id": 18,
        "previousEventId": 17,
        "stateExitedEventDetails": {
            "name": "Generate Random Number",
            "output": "{\"Random Number\":743}",
            "outputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationSucceeded",
        "id": 19,
        "previousEventId": 18,
        "mapIterationSucceededEventDetails": {
            "name": "Map",
            "index": 2
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateEntered",
        "id": 20,
        "previousEventId": 9,
        "stateEnteredEventDetails": {
            "name": "Generate Random Number",
            "input": "4",
            "inputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateExited",
        "id": 21,
        "previousEventId": 20,
        "stateExitedEventDetails": {
            "name": "Generate Random Number",
            "output": "{\"Random Number\":790}",
            "outputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationSucceeded",
        "id": 22,
        "previousEventId": 21,
        "mapIterationSucceededEventDetails": {
            "name": "Map",
            "index": 3
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateEntered",
        "id": 23,
        "previousEventId": 10,
        "stateEnteredEventDetails": {
            "name": "Generate Random Number",
            "input": "5",
            "inputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "PassStateExited",
        "id": 24,
        "previousEventId": 23,
        "stateExitedEventDetails": {
            "name": "Generate Random Number",
            "output": "{\"Random Number\":632}",
            "outputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapIterationSucceeded",
        "id": 25,
        "previousEventId": 24,
        "mapIterationSucceededEventDetails": {
            "name": "Map",
            "index": 4
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapStateSucceeded",
        "id": 26,
        "previousEventId": 25
    },
    {
        "timestamp": "2022-12-08T16:44:07.698000-08:00",
        "type": "MapStateExited",
        "id": 27,
        "previousEventId": 25,
        "stateExitedEventDetails": {
            "name": "Map",
            "output": "[{\"Random Number\":259},{\"Random Number\":776},{\"Random Number\":743},{\"Random Number\":790},{\"Random Number\":632}]",
            "outputDetails": {
                "truncated": false
            }
        }
    },
    {
        "timestamp": "2022-12-08T16:44:07.745000-08:00",
        "type": "ExecutionSucceeded",
        "id": 28,
        "previousEventId": 27,
        "executionSucceededEventDetails": {
            "output": "[{\"Random Number\":259},{\"Random Number\":776},{\"Random Number\":743},{\"Random Number\":790},{\"Random Number\":632}]",
            "outputDetails": {
                "truncated": false
            }
        }
    }
]

}