逻辑应用无法从 Parse JSON 操作中找到值

Question

我有一个由 HTTP 调用触发的逻辑应用程序。此调用附带一组 headers，其中大部分用于不同的 switch 语句。使用我从请求中输入 headers 的 Parse JSON 操作，它们成功解析（图 1），但是对于 headers（searchType）之一，switch 语句的计算结果为 null某些原因（图 2）。我一辈子都弄不明白为什么。

我尝试从头开始重新制作逻辑应用程序，将应用程序完全复制到不同的环境，并尝试使用表达式访问解析值而不是动态内容。当我尝试表达式时，我被告知它是一个无效的表达式（图 3）。此表达式是代码视图中使用的内容的直接副本。

关于我可以做些什么来解决这个问题有什么建议吗？

Successful parsing of headers

parsed header evaluates to null

expression invalid

JSON 复制逻辑应用

{
    "definition": {
        "$schema": "https://schema.management.azure.com/providers/Microsoft.Logic/schemas/2016-06-01/workflowdefinition.json#",
        "actions": {
            "HeadersJson": {
                "inputs": {
                    "content": "@triggerOutputs()['headers']",
                    "schema": {
                        "properties": {
                            "APICallFor": {
                                "type": "string"
                            },
                            "Accept-Encoding": {
                                "type": "string"
                            },
                            "Accept-Language": {
                                "type": "string"
                            },
                            "Connection": {
                                "type": "string"
                            },
                            "Content-Length": {
                                "type": "string"
                            },
                            "Content-Type": {
                                "type": "string"
                            },
                            "Host": {
                                "type": "string"
                            },
                            "User-Agent": {
                                "type": "string"
                            },
                            "searchType": {
                                "type": "string"
                            },
                            "x-ms-action-tracking-id": {
                                "type": "string"
                            },
                            "x-ms-activity-vector": {
                                "type": "string"
                            },
                            "x-ms-client-request-id": {
                                "type": "string"
                            },
                            "x-ms-client-tracking-id": {
                                "type": "string"
                            },
                            "x-ms-correlation-id": {
                                "type": "string"
                            },
                            "x-ms-execution-location": {
                                "type": "string"
                            },
                            "x-ms-tracking-id": {
                                "type": "string"
                            },
                            "x-ms-workflow-id": {
                                "type": "string"
                            },
                            "x-ms-workflow-name": {
                                "type": "string"
                            },
                            "x-ms-workflow-operation-name": {
                                "type": "string"
                            },
                            "x-ms-workflow-resourcegroup-name": {
                                "type": "string"
                            },
                            "x-ms-workflow-run-id": {
                                "type": "string"
                            },
                            "x-ms-workflow-run-tracking-id": {
                                "type": "string"
                            },
                            "x-ms-workflow-subscription-id": {
                                "type": "string"
                            },
                            "x-ms-workflow-system-id": {
                                "type": "string"
                            },
                            "x-ms-workflow-version": {
                                "type": "string"
                            }
                        },
                        "type": "object"
                    }
                },
                "runAfter": {},
                "type": "ParseJson"
            },
            "Switch": {
                "cases": {
                    "Get_Departments": {
                        "actions": {
                            "Switch_3": {
                                "cases": {
                                    "Case": {
                                        "actions": {
                                            "Response_5": {
                                                "inputs": {
                                                    "body": "got to individual",
                                                    "statusCode": 200
                                                },
                                                "kind": "Http",
                                                "runAfter": {},
                                                "type": "Response"
                                            }
                                        },
                                        "case": "individual"
                                    },
                                    "Case_2": {
                                        "actions": {
                                            "Response": {
                                                "inputs": {
                                                    "body": "got to bulk",
                                                    "statusCode": 200
                                                },
                                                "kind": "Http",
                                                "runAfter": {},
                                                "type": "Response"
                                            }
                                        },
                                        "case": "bulk"
                                    }
                                },
                                "default": {
                                    "actions": {
                                        "Response_3": {
                                            "inputs": {
                                                "body": "the searchType parameter is not valid",
                                                "statusCode": 200
                                            },
                                            "kind": "Http",
                                            "runAfter": {},
                                            "type": "Response"
                                        }
                                    }
                                },
                                "expression": "@body('HeadersJson')?['serachType']",
                                "runAfter": {},
                                "type": "Switch"
                            }
                        },
                        "case": "departments"
                    }
                },
                "default": {
                    "actions": {
                        "Response_2": {
                            "inputs": {
                                "body": "the APICallFor header is not valid",
                                "statusCode": 500
                            },
                            "kind": "Http",
                            "runAfter": {},
                            "type": "Response"
                        }
                    }
                },
                "expression": "@body('HeadersJson')?['APICallFor']",
                "runAfter": {
                    "HeadersJson": [
                        "Succeeded"
                    ]
                },
                "type": "Switch"
            }
        },
        "contentVersion": "1.0.0.0",
        "outputs": {},
        "parameters": {},
        "triggers": {
            "manual": {
                "inputs": {
                    "schema": {
                        "properties": {
                            "searchString": {
                                "type": "string"
                            },
                            "searchType": {
                                "type": "string"
                            }
                        },
                        "type": "object"
                    }
                },
                "kind": "Http",
                "operationOptions": "EnableSchemaValidation",
                "type": "Request"
            }
        }
    }
}

Answer 1

你的表达式无效是因为你的表达式中的@，代码视图中使用了@表达式，它应该只是body('HeadersJson')?['searchType'].

至于你的searchType为null，可能是ParseJson schema不正确，所以请确保正确的schema如doc way.

如果你想使用头数据，你不需要将头解析为json，因为数据已经是json格式，但是如果你通过请求传递数据body 你需要解析它。我也测试过它，它可以与 triggerOutputs()['headers']['searchType'] 一起使用，所以只需将它粘贴到表达式中，如果您使用代码视图，它将是 @triggerOutputs()['headers']['searchType'].

逻辑应用无法从 Parse JSON 操作中找到值

Logic app fails to find value from Parse JSON action

azure

azure-logic-apps