Question

所以我试图设置一个基本的POST到API Post方法我把它连接到一个简单的dynamodb。我在下面有以下身体映射模板：

{ 
"TableName": "bars",
"Item": {
  "barid": {
    "S": "$input.path('$.barid')"
  },
  "phone": {
    "S": "$input.path('$.phone')"
  },
  "location": {
    "S": "$input.path('$.location')"
  },
  "happyhour": {
    "L": [
      {
        "M": {
          "Time": {
            "S": "$input.path('$.Time')"
          },
          "Deal": {
            "S": "$input.path('$.Deal')"
          },
          "Day": {
            "S": "$input.path('$.Day')"
          }
        }
      },
      {
        "M": {
          "Time": {
            "S": "$input.path('$.Time')"
          },
          "Deal": {
            "S": "$input.path('$.Deal')"
          },
          "Day": {
            "S": "$input.path('$.Day')"
          }
        }
      },
      {
        "M": {
          "Time": {
            "S": "$input.path('$.Time')"
          },
          "Deal": {
            "S": "$input.path('$.Deal')"
          },
          "Day": {
            "S": "$input.path('$.Day')"
          }
        }
      },
      {
        "M": {
          "Time": {
            "S": "$input.path('$.Time')"
          },
          "Deal": {
            "S": "$input.path('$.Deal')"
          },
          "Day": {
            "S": "$input.path('$.Day')"
          }
        }
      },
      {
        "M": {
          "Time": {
            "S": "$input.path('$.Time')"
          },
          "Deal": {
            "S": "$input.path('$.Deal')"
          },
          "Day": {
            "S": "$input.path('$.Day')"
          }
        }
      },
      {
        "M": {
          "Time": {
            "S": "$input.path('$.Time')"
          },
          "Deal": {
            "S": "$input.path('$.Deal')"
          },
          "Day": {
            "S": "$input.path('$.Day')"
          }
        }
      },
      {
        "M": {
          "Time": {
            "S": "$input.path('$.Time')"
          },
          "Deal": {
            "S": "$input.path('$.Deal')"
          },
          "Day": {
            "S": "$input.path('$.Day')"
          }
        }
      }
    ]
  },
  "name": {
    "S": "$input.path('$.name')"
  }
}
}

以下是我用post：

测试post语句的内容

{
"barid": {
    "S": "005"
},
"happyhour": {
    "L": [{
        "M": {
            "Time": {
                "S": "11AM-9AM"
            },
            "Deal": {
                "S": "$3 Mimosas; $3 Bloody Marys"
            },
            "Day": {
                "S": "Sunday"
            }
        }
    }, {
        "M": {
            "Time": {
                "S": "4PM - 9PM"
            },
            "Deal": {
                "S": "$4 Margaritas, Corona, Corona Light; $3 Bud Light Lime"
            },
            "Day": {
                "S": "Monday"
            }
        }
    }, {
        "M": {
            "Time": {
                "S": "4PM-9PM"
            },
            "Deal": {
                "S": "1/2 Price Burgers; $2 Bud and Bud Light Drafts"
            },
            "Day": {
                "S": "Tuesday"
            }
        }
    }, {
        "M": {
            "Time": {
                "S": "4PM-9PM"
            },
            "Deal": {
                "S": "$2 Drafts; $3 Food Menu"
            },
            "Day": {
                "S": "Wednesday"
            }
        }
    }, {
        "M": {
            "Time": {
                "S": "4PM-9PM"
            },
            "Deal": {
                "S": "$2 Beers, House Liquor, Flavored Vodka; 1/2 Price Wings; $5 Pizzas or Pasta Bowl"
            },
            "Day": {
                "S": "Thursday"
            }
        }
    }, {
        "M": {
            "Time": {
                "S": "4PM-9PM"
            },
            "Deal": {
                "S": "$5 Red Bull House Liquor Cocktails; $5 Wings, Nachos, Sliders, Flatbreads; $5 Finlandia Cocktails and Martinis; $15 Sam Adams Light Buckets"
            },
            "Day": {
                "S": "Friday"
            }
        }
    }, {
        "M": {
            "Time": {
                "S": "None"
            },
            "Deal": {
                "S": "None"
            },
            "Day": {
                "S": "Sunday"
            }
        }
    }]
},
"phone": {
    "S": "(703) 527-1600"
},
"location": {
    "S": "3100 Clarendon Blvd, Arlington, VA 22201"
},
"name": {
    "S": "Mister Days"
}

}

每当我运行它时，似乎它会填充barid，phone和location字段，但会将happyhour数组留空。以下是我在运行测试后在日志中得到的内容。

"TableName": "bars",
"Item": {
  "barid": {
    "S": "{S=005}"
  },
  "phone": {
    "S": "{S=(703) 527-1576}"
  },
  "location": {
    "S": "{S=2500 Hess Road}"
  },
  "happyhour": {
    "L": [
      {
        "M": {
          "Time": {
            "S": ""
          },
          "Deal": {
            "S": ""
          },
          "Day": {
            "S": ""
          }
        }
      },
      {
        "M": {
          "Time": {
            "S": ""
          },
          "Deal": {
            "S": ""
          },
          "Day": {
            "S": ""
          }
        }
      },
      {
        "M": {
          "Time": {
            "S": ""
          },
          "Deal": {
            "S": ""
          },
          "Day": {
            "S": ""
          }
   [TRUNCATED]
Thu Jun 30 15:36:27 UTC 2016 : Endpoint response body before transformations: {"__type":"com.amazon.coral.service#UnknownOperationException"}

不确定我做错了什么，但任何事情都会有所帮助。谢谢！

Answer 1

看起来happyhour包含一个具有名为L的单个属性的对象，该属性包含一个对象数组。您可能希望循环遍历数组，以便无论数组的长度如何，映射模板仍然可以工作。您还需要按照完整路径引用输入中的项目，而不仅仅是名称。

应该看起来像这样......

#set($inputRoot = $input.path('$'))
{ 
"TableName": "bars",
"Item": {
  "barid": {
    "S": "$inputRoot.barid.S"
  },
  "name": {
    "S": "$inputRoot.name.S"
  },
  "phone": {
    "S": "$inputRoot.phone.S"
  },
  "location": {
    "S": "$inputRoot.location.S"
  },

  "happyhour": {
    "L": [
#foreach($elem in $inputRoot.happyhour.L)
      {
        "M": {
          "Time": {
            "S": "$elem.M.Time.S"
          },
          "Deal": {
            "S": "$elem.M.Deal.S"
          },
          "Day": {
            "S": "$elem.M.Day.S"
          }
        }
      }#if($foreach.hasNext),#end
#end
    ]
  }
}

请注意，映射模板顺序和输出顺序不必与输入顺序匹配。此外，您不必保持完全相同的结构。例如，您可以删除所有额外类型信息并输出更清晰的json ...

#set($inputRoot = $input.path('$'))
{ 
"TableName": "bars",
"Item": {
  "barid": "$inputRoot.barid.S",
  "name": "$inputRoot.name.S",
  "phone": "$inputRoot.phone.S",
  "location": "$inputRoot.location.S",
  "happyhour": [
#foreach($elem in $inputRoot.happyhour.L)
      {
          "Time": "$elem.M.Time.S",
          "Deal": "$elem.M.Deal.S",
          "Day": "$elem.M.Day.S"
      }#if($foreach.hasNext),#end
#end
  ]
}

Answer 2

如果您真的想在API中进行映射，这可能不是正确的方法，但您可以将问题留给aws-sdk。

您可以在API和dynamoDB之间创建一个简单的lambda函数。使用Aws提供的一些方法： http://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/DynamoDB/DocumentClient.html

我用这个函数解决了类似的问题：

var AWS = require("aws-sdk");

var docClient = new AWS.DynamoDB.DocumentClient();
var tableName = "tableName";

var saveData = function (data) {

  var params = {
    TableName: tableName,
    Item: data
  };

  docClient.put(params, function (err, data) {
    if (err) {
      console.error("Unable to add item. Error JSON:", JSON.stringify(err, null, 2));
    } else {
      console.log("Added item:", JSON.stringify(data, null, 2));
    }
  });

};

exports.handler = function (event) {
    saveData(event);
};

身体映射模板+ API网关

2 个答案: