#2 connected to mongodb

backend/.env

+DB_CONN_STRING="mongodb://localhost:27017"
+DB_NAME="linksDB"
+LINKS_COLLECTION_NAME="links"
+PORT='3000'
\ No newline at end of file

backend/package-lock.json

@@ -9,8 +9,11 @@
       "version": "1.0.0",
       "license": "ISC",
       "dependencies": {
+        "@types/node": "^18.15.0",
         "cors": "^2.8.5",
-        "express": "^4.18.2"
+        "dotenv": "^16.0.3",
+        "express": "^4.18.2",
+        "mongodb": "^5.1.0"
       },
       "devDependencies": {
         "@types/cors": "^2.8.13",
@@ -139,8 +142,7 @@
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       "resolved": "https://registry.npmjs.org/@types/node/-/node-18.15.0.tgz",
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-      "dev": true
+      "integrity": "sha512-z6nr0TTEOBGkzLGmbypWOGnpSpSIBorEhC4L+4HeQ2iezKCi4f77kyslRwvHeNitymGQ+oFyIWGP96l/DPSV9w=="
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       "dev": true
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+    "node_modules/@types/webidl-conversions": {
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+      "resolved": "https://registry.npmjs.org/@types/webidl-conversions/-/webidl-conversions-7.0.0.tgz",
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+    },
+    "node_modules/@types/whatwg-url": {
+      "version": "8.2.2",
+      "resolved": "https://registry.npmjs.org/@types/whatwg-url/-/whatwg-url-8.2.2.tgz",
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+      "dependencies": {
+        "@types/node": "*",
+        "@types/webidl-conversions": "*"
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       "resolved": "https://registry.npmjs.org/accepts/-/accepts-1.3.8.tgz",
@@ -293,6 +309,14 @@
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+    "node_modules/bson": {
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+      "resolved": "https://registry.npmjs.org/bson/-/bson-5.0.1.tgz",
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+      "engines": {
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@@ -436,6 +460,14 @@
         "node": ">=0.3.1"
       }
     },
+    "node_modules/dotenv": {
+      "version": "16.0.3",
+      "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-16.0.3.tgz",
+      "integrity": "sha512-7GO6HghkA5fYG9TYnNxi14/7K9f5occMlp3zXAuSxn7CKCxt9xbNWG7yF8hTCSUchlfWSe3uLmlPfigevRItzQ==",
+      "engines": {
+        "node": ">=12"
+      }
+    },
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       "version": "0.3.0",
       "resolved": "https://registry.npmjs.org/dynamic-dedupe/-/dynamic-dedupe-0.3.0.tgz",
@@ -690,6 +722,11 @@
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     },
+    "node_modules/ip": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/ip/-/ip-2.0.0.tgz",
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+    },
     "node_modules/ipaddr.js": {
       "version": "1.9.1",
       "resolved": "https://registry.npmjs.org/ipaddr.js/-/ipaddr.js-1.9.1.tgz",
@@ -766,6 +803,12 @@
         "node": ">= 0.6"
       }
     },
+    "node_modules/memory-pager": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/memory-pager/-/memory-pager-1.5.0.tgz",
+      "integrity": "sha512-ZS4Bp4r/Zoeq6+NLJpP+0Zzm0pR8whtGPf1XExKLJBAczGMnSi3It14OiNCStjQjM6NU1okjQGSxgEZN8eBYKg==",
+      "optional": true
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@@ -842,6 +885,47 @@
         "node": ">=10"
       }
     },
+    "node_modules/mongodb": {
+      "version": "5.1.0",
+      "resolved": "https://registry.npmjs.org/mongodb/-/mongodb-5.1.0.tgz",
+      "integrity": "sha512-qgKb7y+EI90y4weY3z5+lIgm8wmexbonz0GalHkSElQXVKtRuwqXuhXKccyvIjXCJVy9qPV82zsinY0W1FBnJw==",
+      "dependencies": {
+        "bson": "^5.0.1",
+        "mongodb-connection-string-url": "^2.6.0",
+        "socks": "^2.7.1"
+      },
+      "engines": {
+        "node": ">=14.20.1"
+      },
+      "optionalDependencies": {
+        "saslprep": "^1.0.3"
+      },
+      "peerDependencies": {
+        "@aws-sdk/credential-providers": "^3.201.0",
+        "mongodb-client-encryption": "^2.3.0",
+        "snappy": "^7.2.2"
+      },
+      "peerDependenciesMeta": {
+        "@aws-sdk/credential-providers": {
+          "optional": true
+        },
+        "mongodb-client-encryption": {
+          "optional": true
+        },
+        "snappy": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/mongodb-connection-string-url": {
+      "version": "2.6.0",
+      "resolved": "https://registry.npmjs.org/mongodb-connection-string-url/-/mongodb-connection-string-url-2.6.0.tgz",
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+      "dependencies": {
+        "@types/whatwg-url": "^8.2.1",
+        "whatwg-url": "^11.0.0"
+      }
+    },
     "node_modules/ms": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/ms/-/ms-2.0.0.tgz",
@@ -952,6 +1036,14 @@
         "node": ">= 0.10"
       }
     },
+    "node_modules/punycode": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/punycode/-/punycode-2.3.0.tgz",
+      "integrity": "sha512-rRV+zQD8tVFys26lAGR9WUuS4iUAngJScM+ZRSKtvl5tKeZ2t5bvdNFdNHBW9FWR4guGHlgmsZ1G7BSm2wTbuA==",
+      "engines": {
+        "node": ">=6"
+      }
+    },
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       "resolved": "https://registry.npmjs.org/qs/-/qs-6.11.0.tgz",
@@ -1053,6 +1145,18 @@
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     },
+    "node_modules/saslprep": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/saslprep/-/saslprep-1.0.3.tgz",
+      "integrity": "sha512-/MY/PEMbk2SuY5sScONwhUDsV2p77Znkb/q3nSVstq/yQzYJOH/Azh29p9oJLsl3LnQwSvZDKagDGBsBwSooag==",
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@@ -1113,6 +1217,28 @@
         "url": "https://github.com/sponsors/ljharb"
       }
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+    "node_modules/smart-buffer": {
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+        "node": ">= 6.0.0",
+        "npm": ">= 3.0.0"
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+      "resolved": "https://registry.npmjs.org/socks/-/socks-2.7.1.tgz",
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+      "dependencies": {
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+        "smart-buffer": "^4.2.0"
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@@ -1132,6 +1258,15 @@
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+    "node_modules/sparse-bitfield": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/sparse-bitfield/-/sparse-bitfield-3.0.3.tgz",
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+      "optional": true,
+      "dependencies": {
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     "node_modules/statuses": {
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       "resolved": "https://registry.npmjs.org/statuses/-/statuses-2.0.1.tgz",
@@ -1190,6 +1325,17 @@
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+    "node_modules/tr46": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/tr46/-/tr46-3.0.0.tgz",
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+      "dependencies": {
+        "punycode": "^2.1.1"
+      },
+      "engines": {
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     "node_modules/tree-kill": {
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@@ -1344,6 +1490,26 @@
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+    "node_modules/webidl-conversions": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/webidl-conversions/-/webidl-conversions-7.0.0.tgz",
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+      "engines": {
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+    "node_modules/whatwg-url": {
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+      "resolved": "https://registry.npmjs.org/whatwg-url/-/whatwg-url-11.0.0.tgz",
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+      "dependencies": {
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@@ -1485,8 +1651,7 @@
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-      "dev": true
+      "integrity": "sha512-z6nr0TTEOBGkzLGmbypWOGnpSpSIBorEhC4L+4HeQ2iezKCi4f77kyslRwvHeNitymGQ+oFyIWGP96l/DPSV9w=="
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       "dev": true
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+    "@types/webidl-conversions": {
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+      "resolved": "https://registry.npmjs.org/@types/webidl-conversions/-/webidl-conversions-7.0.0.tgz",
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+    },
+    "@types/whatwg-url": {
+      "version": "8.2.2",
+      "resolved": "https://registry.npmjs.org/@types/whatwg-url/-/whatwg-url-8.2.2.tgz",
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+      "requires": {
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@@ -1614,6 +1793,11 @@
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+    "bson": {
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+      "resolved": "https://registry.npmjs.org/bson/-/bson-5.0.1.tgz",
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       "dev": true
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+    "dotenv": {
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+      "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-16.0.3.tgz",
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+    "ip": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/ip/-/ip-2.0.0.tgz",
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+    },
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@@ -2101,6 +2321,11 @@
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@@ -2217,6 +2451,20 @@
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+      "version": "4.2.0",
+      "resolved": "https://registry.npmjs.org/smart-buffer/-/smart-buffer-4.2.0.tgz",
+      "integrity": "sha512-94hK0Hh8rPqQl2xXc3HsaBoOXKV20MToPkcXvwbISWLEs+64sBq5kFgn2kJDHb1Pry9yrP0dxrCI9RRci7RXKg=="
+    },
+    "socks": {
+      "version": "2.7.1",
+      "resolved": "https://registry.npmjs.org/socks/-/socks-2.7.1.tgz",
+      "integrity": "sha512-7maUZy1N7uo6+WVEX6psASxtNlKaNVMlGQKkG/63nEDdLOWNbiUMoLK7X4uYoLhQstau72mLgfEWcXcwsaHbYQ==",
+      "requires": {
+        "ip": "^2.0.0",
+        "smart-buffer": "^4.2.0"
+      }
+    },
     "source-map": {
       "version": "0.6.1",
       "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.6.1.tgz",
@@ -2233,6 +2481,15 @@
         "source-map": "^0.6.0"
       }
     },
+    "sparse-bitfield": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/sparse-bitfield/-/sparse-bitfield-3.0.3.tgz",
+      "integrity": "sha512-kvzhi7vqKTfkh0PZU+2D2PIllw2ymqJKujUcyPMd9Y75Nv4nPbGJZXNhxsgdQab2BmlDct1YnfQCguEvHr7VsQ==",
+      "optional": true,
+      "requires": {
+        "memory-pager": "^1.0.2"
+      }
+    },
     "statuses": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/statuses/-/statuses-2.0.1.tgz",
@@ -2270,6 +2527,14 @@
       "resolved": "https://registry.npmjs.org/toidentifier/-/toidentifier-1.0.1.tgz",
       "integrity": "sha512-o5sSPKEkg/DIQNmH43V0/uerLrpzVedkUh8tGNvaeXpfpuwjKenlSox/2O/BTlZUtEe+JG7s5YhEz608PlAHRA=="
     },
+    "tr46": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/tr46/-/tr46-3.0.0.tgz",
+      "integrity": "sha512-l7FvfAHlcmulp8kr+flpQZmVwtu7nfRV7NZujtN0OqES8EL4O4e0qqzL0DC5gAvx/ZC/9lk6rhcUwYvkBnBnYA==",
+      "requires": {
+        "punycode": "^2.1.1"
+      }
+    },
     "tree-kill": {
       "version": "1.2.2",
       "resolved": "https://registry.npmjs.org/tree-kill/-/tree-kill-1.2.2.tgz",
@@ -2364,6 +2629,20 @@
       "resolved": "https://registry.npmjs.org/vary/-/vary-1.1.2.tgz",
       "integrity": "sha512-BNGbWLfd0eUPabhkXUVm0j8uuvREyTh5ovRa/dyow/BqAbZJyC+5fU+IzQOzmAKzYqYRAISoRhdQr3eIZ/PXqg=="
     },
+    "webidl-conversions": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/webidl-conversions/-/webidl-conversions-7.0.0.tgz",
+      "integrity": "sha512-VwddBukDzu71offAQR975unBIGqfKZpM+8ZX6ySk8nYhVoo5CYaZyzt3YBvYtRtO+aoGlqxPg/B87NGVZ/fu6g=="
+    },
+    "whatwg-url": {
+      "version": "11.0.0",
+      "resolved": "https://registry.npmjs.org/whatwg-url/-/whatwg-url-11.0.0.tgz",
+      "integrity": "sha512-RKT8HExMpoYx4igMiVMY83lN6UeITKJlBQ+vR/8ZJ8OCdSiN3RwCq+9gH0+Xzj0+5IrM6i4j/6LuvzbZIQgEcQ==",
+      "requires": {
+        "tr46": "^3.0.0",
+        "webidl-conversions": "^7.0.0"
+      }
+    },
     "wrappy": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",

backend/package.json

@@ -10,8 +10,11 @@
   "author": "",
   "license": "ISC",
   "dependencies": {
+    "@types/node": "^18.15.0",
     "cors": "^2.8.5",
-    "express": "^4.18.2"
+    "dotenv": "^16.0.3",
+    "express": "^4.18.2",
+    "mongodb": "^5.1.0"
   },
   "devDependencies": {
     "@types/cors": "^2.8.13",

backend/src/index.ts

 import express, {Express} from 'express';
-import {linksRouter} from './routes/linksRouter';
+import {linksRouter} from './routes/links.router';
+import {connectToDatabase} from './services/database.service';
 
 const app: Express = express();
 app.use(express.json());
 app.use('/links', linksRouter);
 
-app.listen(3000, () => {
-  console.log(`Server is listening on port 3000`);
-});
+connectToDatabase()
+  .then(() => {
+    app.use('/links', linksRouter);
+    app.listen(process.env.PORT, () => {
+      console.log(`Server started at http://localhost:${process.env.PORT}`);
+    });
+  })
+  .catch((error: Error) => {
+    console.log('Database connection failed');
+    process.exit();
+  });

backend/src/models/links.ts

+import {ObjectId} from 'mongodb';
+
+export default class Link {
+  constructor(public originalUrl: string, public id?: ObjectId) {}
+}

backend/src/routes/links.router.ts

+import express, {Router, Request, Response} from 'express';
+import {ObjectId} from 'mongodb';
+import {collections} from '../services/database.service';
+import Link from '../models/links';
+
+export const linksRouter: Router = express.Router();
+
+linksRouter.get('/', (req: Request, res: Response) => {
+  try {
+    res.send('Hello');
+  } catch (error: unknown) {
+    const err = error as Error;
+    res.status(500).send(err.message);
+  }
+});
+
+linksRouter.post('/', async (req: Request, res: Response) => {
+  try {
+    const newLink = req.body as Link;
+    const result = await collections.links?.insertOne(newLink);
+    if (result) {
+      res
+        .status(201)
+        .send(`Successfully created a new link with id ${result.insertedId}`);
+    } else {
+      res.status(500).send('Failed to create a new link.');
+    }
+  } catch (err: unknown) {
+    const error = err as Error;
+    res.status(500).send(error.message);
+  }
+});

backend/src/routes/linksRouter.ts

-import express, {Router, Request, Response} from 'express';
-
-export const linksRouter: Router = express.Router();
-
-linksRouter.get('/', (req: Request, res: Response) => {
-  res.send('Hello');
-});
-
-linksRouter.post('/', (req: Request, res: Response) => {
-  res.send('Hello');
-});

backend/src/services/database.service.ts

+import * as mongoDB from 'mongodb';
+import * as dotenv from 'dotenv';
+export const collections: {links?: mongoDB.Collection} = {};
+
+export const connectToDatabase = async () => {
+  dotenv.config();
+  const client: mongoDB.MongoClient = new mongoDB.MongoClient(
+    process.env.DB_CONN_STRING
+  );
+  await client.connect();
+  const db: mongoDB.Db = client.db(process.env.DB_NAME);
+  const linksCollection: mongoDB.Collection = db.collection(
+    process.env.LINKS_COLLECTION_NAME
+  );
+  collections.links = linksCollection;
+  console.log('Connected to database');
+};

backend/src/types/environment.d.ts

+declare global {
+  namespace NodeJS {
+    interface ProcessEnv {
+      PORT: string;
+      DB_CONN_STRING: string;
+      DB_NAME: string;
+      LINKS_COLLECTION_NAME: string;
+    }
+  }
+}
+
+export {};