connection to mongodb works with mongoose

package-lock.json

@@ -2262,6 +2262,16 @@
         "@types/node": "*"
       }
     },
+    "@types/mongoose": {
+      "version": "5.10.2",
+      "resolved": "https://registry.npmjs.org/@types/mongoose/-/mongoose-5.10.2.tgz",
+      "integrity": "sha512-n23tptnyVk0FDew/5YMG9eee5DQGRq2YLyFxm5b04V5QzCmomX6L8sA4BUv1s4ibr+HP9gCABIEhcItFOQi/dA==",
+      "dev": true,
+      "requires": {
+        "@types/mongodb": "*",
+        "@types/node": "*"
+      }
+    },
     "@types/node": {
       "version": "12.19.1",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-12.19.1.tgz",

package.json

@@ -47,6 +47,7 @@
     "@types/express": "^4.17.9",
     "@types/jasmine": "~3.5.0",
     "@types/jasminewd2": "~2.0.3",
+    "@types/mongoose": "^5.10.2",
     "@types/node": "^12.11.1",
     "codelyzer": "^6.0.0",
     "jasmine-core": "~3.5.0",
@@ -58,6 +59,7 @@
     "karma-jasmine-html-reporter": "^1.5.0",
     "protractor": "~7.0.0",
     "ts-node": "~8.3.0",
+    "ts-node-dev": "^1.0.0",
     "tslint": "~6.1.0",
     "typescript": "^3.9.7"
   },

src/index.ts

 import express from 'express';
+import mongoose from 'mongoose';
 import { json } from 'body-parser';
 import { todoRouter } from './routes/todo'
 
@@ -6,6 +7,14 @@ const app = express()
 app.use(json())
 app.use(todoRouter)
 
+mongoose.connect('mongodb://localhost:27017/todo', {
+    useCreateIndex: true,
+    useNewUrlParser: true,
+    useUnifiedTopology: true
+}, () => {
+    console.log('connected to database')
+})
+
 app.listen(3000, () => {
     console.log('server is listening on port 3000')
 })
\ No newline at end of file