Bot for MS Teams using outgoing webhook service

README.md

teams-webhook-service

bot using teams' outgoing webhook

npm install
sls deploy -v

handler.js

'use strict';

const uuidv4 = require('uuid/v4');
const crypto = require('crypto');
const rp = require('request-promise');

const sharedSecret = process.env.SHARED_SECRET;
const bufSecret = Buffer(sharedSecret, "base64");

const commands = [
  {
    'command': 'uuidv4',
    'function': genUUIDv4
  },
  {
    'command': 'usdjp',
    'function': usdjp
  },
  {
    'command': 'exchange',
    'function': exchange
  },
  {
    'command': 'omikuji',
    'function': omikuji
  },
  {
    'command': 'gohan',
    'function': gohan
  },
  {
    'command': 'image',
    'function': imageTest
  },
  {
    'command': 'debug',
    'function': debug
  },
  {
    'command': 'commands',
    'function': getCommands
  }
];

module.exports.hello = async (event, context, callback) => {
  console.log(`body = ${event.body}`);
  //console.log(`header = ${JSON.stringify(event.headers)}`);

  const auth = event.headers['Authorization'];

  if (checkValid(auth, event.body)) {
    console.log(`success !!!`);
    const bodyObj = JSON.parse(event.body);

    const replacedReqText = bodyObj.text.replace(' ', ' ')
    const splits = replacedReqText.split(' ');
    const command = splits[1].split('\n')[0];
    console.log(`command = ${command}, splits = ${splits}`);
    
    let responseBody;
    const selected = selectCommand(command)
    if (selected.length == 0) {
      responseBody = {
        "type": "message",
        "text": 'no match',
      }
    } else {
      responseBody = await selected[0].function(bodyObj);
    }

    // success
    const response = {
      statusCode: 200,
      body: JSON.stringify(responseBody),
    };
    callback(null, response);
  } else {
    console.log(`failure !!!`);
    // failure
    const response = {
      statusCode: 401,
      body: JSON.stringify({
        type: "message",
        text: `auth error`
      }),
    };
    callback(null, response);
  }
};

function checkValid(auth, body) {
  const msgBuf = Buffer.from(body, 'utf8');
  const msgHash = "HMAC " + crypto.createHmac('sha256', bufSecret).update(msgBuf).digest("base64");

  console.log(`msgBuf = ${msgBuf}`);
  console.log(`msgHash = ${msgHash}`);

  return msgHash === auth;
}

function selectCommand(command) {
  return commands.filter(x => x.command === command);
}

// command ---------------------------
function genUUIDv4(requestBody) {
  return new Promise((resolve, reject) => {
    console.log(`command: genUUIDv4`)
    resolve(
      {
        "type": "message",
        "text": uuidv4()
      }
    );
  });
}

function usdjp(requestBody) {
  return rp('https://www.gaitameonline.com/rateaj/getrate').then((result) => {
    const resultObj = JSON.parse(result);
    const udjpy = resultObj.quotes
      .filter(x => x.currencyPairCode == 'USDJPY')
      .map(x => `bid: ${x.bid}, ask: ${x.ask}`);
    
      return {
        "type": "message",
        "text": udjpy[0]
      };
  });
}

function exchange(requestBody) {
  return rp('https://www.gaitameonline.com/rateaj/getrate').then((result) => {
    const replacedReqText = requestBody.text.replace(' ', ' ')
    const splits = replacedReqText.split(' ');
    const currencyPairCode = splits[2].split('\n')[0];

    const resultObj = JSON.parse(result);
    const rate = resultObj.quotes
      .filter(x => x.currencyPairCode.toUpperCase() == currencyPairCode.toUpperCase())
      .map(x => `bid: ${x.bid}, ask: ${x.ask}`);
    
      return {
        "type": "message",
        "text": rate[0]
      };
  });
}

function imageTest(requestBody) {
  return new Promise((resolve, reject) => {
    resolve(
      {
        "type": "message",
        "text": "https://pbs.twimg.com/media/DcZFlI-U0AASCL5.jpg",
        "attachments": [{
          "contentType": "image/jpg",
          "contentUrl": "https://pbs.twimg.com/media/DcZFlI-U0AASCL5.jpg",
        }]
      }
    );
  });
}

function debug(body) {
  return new Promise((resolve, reject) => {
    resolve(
      {
        "type": "message",
        "text": JSON.stringify(body),
      }
    );
  });
}

function getRandomInt(max) {
  return Math.floor(Math.random() * Math.floor(max));
}

function omikuji(body) {
  return new Promise((resolve, reject) => {
    const types = [
      "健康",
      "体調",
      "仕事",
      "交渉",
      "縁談",
      "金運",
      "商売",
      "学問"
    ];
    const results = [
      "大吉",
      "中吉",
      "小吉",
      "にゃ～ん",
      "んなぁ"
    ];

    resolve(
      {
        "type": "message",
        "text": types.map(type => `「${type}」は、${results[getRandomInt(results.length - 1)]}です。`)
          .reduce((acc, x) => acc + "\n\n" + x)
      }
    );
  });
}

function gohan(body) {
  return new Promise((resolve, reject) => {
    const recommends = [
      "寿司",
      "刺し身",
      "海鮮丼",
      "丼もの",
      "親子丼",
      "牛丼",
      "おでん",
      "うどん",
      "ラーメン",
      "味噌ラーメン",
      "醤油ラーメン",
      "素麺",
      "たこ焼き",
      "お好み焼き",
      "もんじゃ焼き",
      "豆腐料理",
      "もんじゃ焼き",
      "メキシコ料理",
      "シンガポール料理",
      "タイ料理",
      "中華料理",
      "チャーハン",
      "小籠包",
      "餃子",
      "パスタ",
      "ピザ",
      "カレー",
      "ハヤシライス",
      "オムライス",
      "ハンバーグ",
      "ハンバーガー",
      "焼き肉",
      "ステーキ",
      "鉄板焼き",
      "ジンギスカン",
      "馬肉料理",
      "串焼き",
      "焼き鳥",
      "ローストビーフ丼",
      "鍋料理",
      "おにぎり",
      "すき焼き",
      "しゃぶしゃぶ"
    ];
    resolve(
      {
        "type": "message",
        "text": `今日のご飯は「${recommends[getRandomInt(recommends.length - 1)]}」とかどうでしょう。`
      }
    );
  });
}

function getCommands(body) {
  return new Promise((resolve, reject) => {
    resolve(
      {
        "type": "message",
        "text": JSON.stringify(commands.map((x) => x.command)),
      }
    );
  });
}

package.json

{
  "name": "teams-webhook-service",
  "version": "1.0.0",
  "description": "",
  "main": "handler.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "request": "^2.87.0",
    "request-promise": "^4.2.2",
    "uuid": "^3.2.1"
  }
}

serverless.yml

service: teams-webhook-service

provider:
  name: aws
  runtime: nodejs8.10
  region: ap-northeast-1


# you can add statements to the Lambda function's IAM Role here
#  iamRoleStatements:
#    - Effect: "Allow"
#      Action:
#        - "s3:ListBucket"
#      Resource: { "Fn::Join" : ["", ["arn:aws:s3:::", { "Ref" : "ServerlessDeploymentBucket" } ] ]  }
#    - Effect: "Allow"
#      Action:
#        - "s3:PutObject"
#      Resource:
#        Fn::Join:
#          - ""
#          - - "arn:aws:s3:::"
#            - "Ref" : "ServerlessDeploymentBucket"
#            - "/*"

# you can define service wide environment variables here
#  environment:
#    variable1: value1

# you can add packaging information here
#package:
#  include:
#    - include-me.js
#    - include-me-dir/**
#  exclude:
#    - exclude-me.js
#    - exclude-me-dir/**

functions:
  hello:
    handler: handler.hello
    events:
      - http:
          path: api/hello
          method: post

#    The following are a few example events you can configure
#    NOTE: Please make sure to change your handler code to work with those events
#    Check the event documentation for details
#    events:
#      - http:
#          path: users/create
#          method: get
#      - s3: ${env:BUCKET}
#      - schedule: rate(10 minutes)
#      - sns: greeter-topic
#      - stream: arn:aws:dynamodb:region:XXXXXX:table/foo/stream/1970-01-01T00:00:00.000
#      - alexaSkill: amzn1.ask.skill.xx-xx-xx-xx
#      - alexaSmartHome: amzn1.ask.skill.xx-xx-xx-xx
#      - iot:
#          sql: "SELECT * FROM 'some_topic'"
#      - cloudwatchEvent:
#          event:
#            source:
#              - "aws.ec2"
#            detail-type:
#              - "EC2 Instance State-change Notification"
#            detail:
#              state:
#                - pending
#      - cloudwatchLog: '/aws/lambda/hello'
#      - cognitoUserPool:
#          pool: MyUserPool
#          trigger: PreSignUp

#    Define function environment variables here
#    environment:
#      variable2: value2

# you can add CloudFormation resource templates here
#resources:
#  Resources:
#    NewResource:
#      Type: AWS::S3::Bucket
#      Properties:
#        BucketName: my-new-bucket
#  Outputs:
#     NewOutput:
#       Description: "Description for the output"
#       Value: "Some output value"