首先

这次我们将在上次的基础上继续开发DELETE（删除特定用户）、GET（获取所有用户）、PATCH（更新特定用户）功能。

删除（针对目标用户的删除）

根据指定的id，将删除目标用户。

创建和配置Lambda函数

源泉

'use strict';
const AWS = require('aws-sdk');
const myRegion = "us-east-2";

AWS.config.update({ region: myRegion});

exports.handler = async (event, context) => {
  const documentClient = new AWS.DynamoDB.DocumentClient({ region: myRegion});

  let responseBody = "";
  let statusCode = 0;

  const { id } = event.pathParameters;

  const params = {
    TableName: "Users",
    Key: {
      id: id
    }
  };

  try {
    const data = await documentClient.delete(params).promise();
    responseBody = JSON.stringify(data);
    statusCode = 204;
  } catch (err) {
    responseBody = `Unable to delete user: ${err}`;
    statusCode = 403;
  }

  const response = {
    statusCode: statusCode,
    headers: {
      "Content-Type": "application/json"
    },
    body: responseBody
  };

  return response;
};

创建和设置方法 (CJ-Language Model)

执行测试并确认

获取（获取所有用户）

当执行GET方法时，确保所有用户都被获取。

创建和设置Lambda函数

'use strict';
const AWS = require('aws-sdk');
const myRegion = "us-east-2";

AWS.config.update({ region: myRegion});

exports.handler = async (event, context) => {
  const documentClient = new AWS.DynamoDB.DocumentClient({ region: myRegion});

  let responseBody = "";
  let statusCode = 0;

  const params = {
    TableName: "Users"
  };

  try {
    const data = await documentClient.scan(params).promise();
    responseBody = JSON.stringify(data);
    statusCode = 200;
  } catch (err) {
    responseBody = `Unable to get users: ${err}`;
    statusCode = 403;
  }

  const response = {
    statusCode: statusCode,
    headers: {
      "Content-Type": "application/json"
    },
    body: responseBody
  };

  return response;
};

创建和设置方法

进行考试并确认

进行补丁(更新目标用户)

当执行PATCH方法时，确保目标用户已被更新。

创建和配置Lambda函数

/**
 * 対象のユーザ情報を更新する
 */
'use strict';
const AWS = require('aws-sdk');
const myRegion = "us-east-2";

AWS.config.update({ region: myRegion});

exports.handler = async (event, context) => {
  const documentClient = new AWS.DynamoDB.DocumentClient({ region: myRegion});

  let responseBody = "";
  let statusCode = 0;

  const { id, firstname, lastname } = JSON.parse(event.body);

  const params = {
    TableName: "Users",
    Key: {
        id: id
    },
    UpdateExpression: "set firstname = :fname, lastname = :lname",
    ExpressionAttributeValues: {
        ":fname": firstname,
        ":lname": lastname
    },
    ReturnValues: "UPDATED_NEW"
  };

  try {
    const data = await documentClient.update(params).promise();
    responseBody = JSON.stringify(data);
    statusCode = 204;
  } catch (err) {
    responseBody = `Unable to patch user ${err}`;
    statusCode = 403;
  }

  const response = {
    statusCode: statusCode,
    headers: {
      "Content-Type": "application/json"
    },
    body: responseBody
  };

  return response;
};

创建和设置方法

进行测试并确认

{
    "id": "02",
    "firstname": "update_firstname",
    "lastname": "update_lastname"
}

结束

我已经使用无服务器REST API创建了CRUD环境的配置。
下一步，我打算结合API网关+Lambda（NodeJS）+S3。