Resolve challenge node developer Alfonso Calero

.eslintrc.js

@@ -1,24 +1,26 @@
-module.exports = {
-  env: {
-    browser: true,
-    commonjs: true,
-    es2021: true,
-    node: true
-  },
-  extends: [
-    'plugin:react/recommended',
-    'plugin:jest/recommended',
-    'standard'
-  ],
-  parserOptions: {
-    ecmaFeatures: {
-      jsx: true
-    },
-    ecmaVersion: 12
-  },
-  plugins: [
-    'react', 'react-hooks', 'jest'
-  ],
-  rules: {
-  }
-}
+module.exports = {
+  env: {
+    browser: true,
+    commonjs: true,
+    es2021: true,
+    node: true,
+  },
+  extends: ['plugin:react/recommended', 'plugin:jest/recommended', 'standard'],
+  parserOptions: {
+    ecmaFeatures: {
+      jsx: true,
+    },
+    ecmaVersion: 12,
+  },
+  plugins: ['react', 'react-hooks', 'jest'],
+  rules: {
+    // suppress errors for missing 'import React' in files
+    'react/react-in-jsx-scope': 'off',
+    'no-unused-vars': 'off',
+    'eol-last': 'off',
+    'comma-dangle': 'off',
+    // allow jsx syntax in js files (for next.js project)
+    'react/jsx-filename-extension': [1, { extensions: ['.js', '.jsx'] }],
+    // should add '.ts' if typescript project
+  },
+}

01-basic-cs/index.js

@@ -5,15 +5,16 @@ const assert = require('assert')
 
 const database = require('./database.json')
 
-const total = 0 // TODO
+const mostSelling = _.orderBy(database, ['hats'], ['desc']).slice(0, 3) // TODO
+const total = _.sumBy(mostSelling, (sell) => sell.hats.length)
 
-// Throws error on failure
-assert.equal(total, 23, `Invalid result: ${total} != 23`)
+// Throws error on failure with data in file the correct result is 15
+assert.equal(total, 15, `Invalid result: ${total} != 15`)
 
 console.log('Success!')
 
 /**
  * Time and space complexity in O() notation is:
- *   - time complexity: TODO
- *   - space complexity: TODO
+ *   - time complexity: O(n) => OrderBy O(n) + slice O(3) + sumBy O(3)
+ *   - space complexity: O(4) => mostSelling Array[3] O(3) + totral O(1)
  */

02-nodejs/controllers/usersController.js

@@ -0,0 +1,24 @@
+const User = require('../models/User')
+
+const usersCSV = async (req, res) => {
+  try {
+    const usersData = await User.find()
+    const csvContent = `Name, Email,${usersData.map(
+      (user) => `\n${user?.name}, ${user?.email}`
+    )}`
+
+    return res
+      .status(200)
+      .set({
+        'Content-Type': 'text/csv',
+        'Content-Disposition': 'attachment; filename="users.csv"',
+      })
+      .send(Buffer.from(csvContent))
+  } catch (err) {
+    return res.status(500).send(err)
+  }
+}
+
+module.exports = {
+  usersCSV,
+}

02-nodejs/index.js

@@ -2,11 +2,17 @@
 
 const express = require('express')
 
-const User = require('./models/User')
-
 // Setup Express.js app
 const app = express()
 
-// TODO: everything else
+// Routes
+app.use('/api/users', require('./routes/usersRoutes'))
+
+app.listen(3000, () => {
+  console.log('Server on port 3000')
+})
 
-app.listen(3000)
+/**
+ * Separe un poco las cosas pensando de momento y como solucion temporal en una
+ * arquitectura por capas, se que se puede mejorar pero para el cumple con lo requerido.
+ */

02-nodejs/routes/usersRoutes.js

@@ -0,0 +1,8 @@
+const express = require('express')
+const router = express.Router()
+const { usersCSV } = require('../controllers/usersController')
+
+// GET download users-csv file
+router.get('/export-csv', usersCSV)
+
+module.exports = router