Start Project

+node_modules/
+.env
\ No newline at end of file

+var express = require('express');
+var app = express();
+const line = require('@line/bot-sdk');
+require("dotenv").config({path : '.env'});
+
+
+//papago api
+var request = require('request');
+
+//번역 api_url
+var translate_api_url = 'https://openapi.naver.com/v1/papago/n2mt';
+
+//언어감지 api_url
+var languagedetect_api_url = 'https://openapi.naver.com/v1/papago/detectLangs'
+
+// Naver Auth Key
+//새로 발급받은 naver papago api id, pw 입력
+var client_id = process.env.client_id;
+var client_secret = process.env.client_secret;
+const config = {
+  channelAccessToken: process.env.channelAccessToken,
+  channelSecret: process.env.channelSecret,
+};
+
+
+// create LINE SDK client
+const client = new line.Client(config);
+
+// create Express app
+// about Express itself: https://expressjs.com/
+
+// register a webhook handler with middleware
+// about the middleware, please refer to doc
+app.post('/webhook', line.middleware(config), (req, res) => {
+  Promise
+    .all(req.body.events.map(handleEvent))
+    .then((result) => res.json(result))
+    .catch((err) => {
+      console.error(err);
+      res.status(200).end();
+    });
+});
+
+// event handler
+function handleEvent(event) {
+  if (event.type !== 'message' || event.message.type !== 'text') {
+    // ignore non-text-message event
+    return Promise.resolve(null);
+  }
+  return new Promise(function(resolve, reject) {
+    //언어 감지 option
+    var detect_options = {
+      url : languagedetect_api_url,
+      form : {'query': event.message.text},
+      headers: {'X-Naver-Client-Id': client_id, 'X-Naver-Client-Secret': client_secret}
+    };
+
+    //papago 언어 감지
+    request.post(detect_options,function(error,response,body){
+      console.log(response.statusCode);
+      if(!error && response.statusCode == 200){
+        var detect_body = JSON.parse(response.body);
+        var source = '';
+        var target = '';
+        var result = { type: 'text', text:''};
+
+        //언어 감지가 제대로 됐는지 확인
+        console.log(detect_body.langCode);
+
+
+        //번역은 한국어->영어 / 영어->한국어만 지원
+        if(detect_body.langCode == 'ko'||detect_body.langCode == 'en'){
+          source = detect_body.langCode == 'ko' ? 'ko':'en';
+          target = source == 'ko' ? 'en':'ko';
+          //papago 번역 option
+          var options = {
+              url:  translate_api_url,
+              // 한국어(source : ko), 영어(target: en), 카톡에서 받는 메시지(text)
+              form: {'source':source, 'target':target, 'text':event.message.text},
+              headers: {'X-Naver-Client-Id': client_id, 'X-Naver-Client-Secret': client_secret}
+          };
+
+          // Naver Post API
+          request.post(options, function(error, response, body){
+              // Translate API Sucess
+              if(!error && response.statusCode == 200){
+                  // JSON
+                  var objBody = JSON.parse(response.body);
+                  // Message 잘 찍히는지 확인
+
+                  result.text = objBody.message.result.translatedText;
+                  console.log(result.text);
+                  //번역된 문장 보내기
+                  client.replyMessage(event.replyToken,result).then(resolve).catch(reject);
+              }
+          });
+        }
+        // 메시지의 언어가 영어 또는 한국어가 아닐 경우
+        else{
+          result.text = '언어를 감지할 수 없습니다. \n 번역 언어는 한글 또는 영어만 가능합니다.';
+          client.replyMessage(event.replyToken,result).then(resolve).catch(reject);
+        }
+
+      }
+
+    });
+
+    });
+  }
+
+app.listen(3000, function () {
+  console.log('Linebot listening on port 3000!');
+});

+#!/usr/bin/env node
+
+/**
+ * Module dependencies.
+ */
+
+var app = require('../app');
+var debug = require('debug')('project:server');
+var http = require('http');
+
+/**
+ * Get port from environment and store in Express.
+ */
+
+var port = normalizePort(process.env.PORT || '3000');
+app.set('port', port);
+
+/**
+ * Create HTTP server.
+ */
+
+var server = http.createServer(app);
+
+/**
+ * Listen on provided port, on all network interfaces.
+ */
+
+server.listen(port);
+server.on('error', onError);
+server.on('listening', onListening);
+
+/**
+ * Normalize a port into a number, string, or false.
+ */
+
+function normalizePort(val) {
+  var port = parseInt(val, 10);
+
+  if (isNaN(port)) {
+    // named pipe
+    return val;
+  }
+
+  if (port >= 0) {
+    // port number
+    return port;
+  }
+
+  return false;
+}
+
+/**
+ * Event listener for HTTP server "error" event.
+ */
+
+function onError(error) {
+  if (error.syscall !== 'listen') {
+    throw error;
+  }
+
+  var bind = typeof port === 'string'
+    ? 'Pipe ' + port
+    : 'Port ' + port;
+
+  // handle specific listen errors with friendly messages
+  switch (error.code) {
+    case 'EACCES':
+      console.error(bind + ' requires elevated privileges');
+      process.exit(1);
+      break;
+    case 'EADDRINUSE':
+      console.error(bind + ' is already in use');
+      process.exit(1);
+      break;
+    default:
+      throw error;
+  }
+}
+
+/**
+ * Event listener for HTTP server "listening" event.
+ */
+
+function onListening() {
+  var addr = server.address();
+  var bind = typeof addr === 'string'
+    ? 'pipe ' + addr
+    : 'port ' + addr.port;
+  debug('Listening on ' + bind);
+}

+{
+  "name": "linebot",
+  "version": "1.0.0",
+  "description": "",
+  "main": "app.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "start": "node server.js"
+  },
+  "author": "김형도",
+  "license": "MIT",
+  "dependencies": {
+    "@line/bot-sdk": "^6.8.3",
+    "dotenv": "^8.2.0",
+    "express": "^4.17.1",
+    "request": "^2.88.0",
+    "request-promise-native": "^1.0.8"
+  }
+}