Dynamodb-批处理写入不工作（nodejs）

Question

我正在使用lambda、API网关和Dynamodb

我正在创建一个batchWrite函数，在一个函数中上载25个以上的项目

但我发现，当我上传35个项目时，前25个项目成功上传到dynamodb，但最后10个项目失败，但没有记录任何错误

该函数在node.js中编写

'use strict'
const AWS = require('aws-sdk');
const sha1 = require('sha1');
const documentClient = new AWS.DynamoDB.DocumentClient();

exports.handler = async function (event, context, callback) {

    let responseBody = "";
    let statusCode = 0;

    const { excelObject } = JSON.parse(event.body);

    if(excelObject){
        await uploadFileByBatch(excelObject)
    }

    const response = {
        statusCode: statusCode,
        headers:{
            "Content-Type": "application/json",
            "access-control-allow-origin": "*"
        },
        body: responseBody
    }

    console.log(response)
    return response
}

let uploadFileByBatch = async function (payload) {

    var items = [];
    var params={};

    if(payload.length > 25){
        console.log("> 25")
        let newObj = payload.slice(0,25)
        payload.splice(0,25)

        console.log("new Payload length")
        console.log(payload.length)

        newObj.forEach(obj =>{
            let hash = sha1(Buffer.from(new Date().toString()+ Math.random()));
            items.push(
                {
                    PutRequest:{
                        Item: {
                            id: obj.id?obj.id:hash,
                            organization_EN: obj.organization_EN,
                            email: obj.email,
                            isActive: obj.isActive
                        }
                    }
                }
            )
        })

        params = {
            RequestItems:{
                "Community": items
            }
        }
        console.log(params)
        try{
            const data = await documentClient.batchWrite(params).promise();
        }catch(err){
            console.log(err)
        }
        uploadFileByBatch(payload)
    }else{
        console.log("less than 25")
        payload.forEach(obj =>{
            let hash = sha1(Buffer.from(new Date().toString()+ Math.random()));
            items.push(
                {
                    PutRequest:{
                        Item: {
                            id: obj.id?obj.id:hash,
                            organization_EN: obj.organization_EN,
                            email: obj.email,
                            isActive: obj.isActive
                        }
                    }
                }
            )
        })
        params = {
            RequestItems:{
                "Community": items
            }
        }
        console.log(params)
        try{
            console.log("first BatchWrite")
            const data = await documentClient.batchWrite(params).promise();
            console.log("first Data")
        }catch(err){
            console.log(err)
        }
    }

}

日志如下所示。

>25
New Payload length
10

{
  RequestItems: {
    'Community': [
      [Object], [Object], [Object],
      [Object], [Object], [Object],
      [Object], [Object], [Object],
      [Object], [Object], [Object],
      [Object], [Object], [Object],
      [Object], [Object], [Object],
      [Object], [Object], [Object],
      [Object], [Object], [Object],
      [Object]
    ]
  }
}

first BatchWrite
Less than 25
{
  RequestItems: {
    'Community': [
      [Object], [Object],
      [Object], [Object],
      [Object], [Object],
      [Object], [Object],
      [Object], [Object]
    ]
  }
}

{
  statusCode: 0,
  headers: {
    'Content-Type': 'application/json',
    'access-control-allow-origin': '*'
  },
  body: ''
}

Answer 1

对于DynamoDB的batchWrite函数，您不能在一次请求中上载超过25个

如果以下一项或多项为真，DynamoDB将拒绝整个批处理写入操作：

• BatchWriteItem请求中指定的一个或多个表不存在

您可以在此处检索有关此的信息https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_BatchWriteItem.html

有很多方法可以处理大批量操作，您可以执行25个并行请求，但您应该小心。