Add full_server folder

Author: Mar-Issah

0x05-Node_JS_basic/full_server/controllers/AppController.js

@@ -0,0 +1,12 @@
+/**
+ * Contains the route handlers.
+ *
+ */
+class AppController {
+  static getHomepage(request, response) {
+    response.status(200).send('Hello Holberton School!');
+  }
+}
+
+export default AppController;
+module.exports = AppController;

0x05-Node_JS_basic/full_server/controllers/StudentsController.js

@@ -0,0 +1,70 @@
+import readDatabase from '../utils';
+
+/**
+ * The list of supported majors.
+ */
+const VALID_MAJORS = ['CS', 'SWE'];
+
+/**
+ * Contains the student-related route handlers.
+ *
+ */
+class StudentsController {
+  static getAllStudents(request, response) {
+    const dataPath = process.argv.length > 2 ? process.argv[2] : '';
+
+    readDatabase(dataPath)
+      .then((studentGroups) => {
+        const responseParts = ['This is the list of our students'];
+        const cmpFxn = (a, b) => {
+          if (a[0].toLowerCase() < b[0].toLowerCase()) {
+            return -1;
+          }
+          if (a[0].toLowerCase() > b[0].toLowerCase()) {
+            return 1;
+          }
+          return 0;
+        };
+
+        for (const [field, group] of Object.entries(studentGroups).sort(cmpFxn)) {
+          responseParts.push(
+            [
+              `Number of students in ${field}: ${group.length}.`,
+              'List:',
+              group.map((student) => student.firstname).join(', '),
+            ].join(' ')
+          );
+        }
+        response.status(200).send(responseParts.join('\n'));
+      })
+      .catch((err) => {
+        response.status(500).send(err instanceof Error ? err.message : err.toString());
+      });
+  }
+
+  static getAllStudentsByMajor(request, response) {
+    const dataPath = process.argv.length > 2 ? process.argv[2] : '';
+    const { major } = request.params;
+
+    if (!VALID_MAJORS.includes(major)) {
+      response.status(500).send('Major parameter must be CS or SWE');
+      return;
+    }
+    readDatabase(dataPath)
+      .then((studentGroups) => {
+        let responseText = '';
+
+        if (Object.keys(studentGroups).includes(major)) {
+          const group = studentGroups[major];
+          responseText = `List: ${group.map((student) => student.firstname).join(', ')}`;
+        }
+        response.status(200).send(responseText);
+      })
+      .catch((err) => {
+        response.status(500).send(err instanceof Error ? err.message : err.toString());
+      });
+  }
+}
+
+export default StudentsController;
+module.exports = StudentsController;

0x05-Node_JS_basic/full_server/routes/index.js

@@ -0,0 +1,17 @@
+import AppController from '../controllers/AppController';
+import StudentsController from '../controllers/StudentsController';
+
+/**
+ * Binds the routes to the appropriate handler in the
+ * given Express application.
+ * @param {Express} app The Express application.
+ * @returns {void}
+ */
+const mapRoutes = (app) => {
+  app.get('/', AppController.getHomepage);
+  app.get('/students', StudentsController.getAllStudents);
+  app.get('/students/:major', StudentsController.getAllStudentsByMajor);
+};
+
+export default mapRoutes;
+module.exports = mapRoutes;

0x05-Node_JS_basic/full_server/server.js

@@ -0,0 +1,13 @@
+import express from 'express';
+import mapRoutes from './routes';
+
+const app = express();
+const PORT = 1245;
+
+mapRoutes(app);
+app.listen(PORT, () => {
+  console.log(`Server listening on PORT ${PORT}`);
+});
+
+export default app;
+module.exports = app;

0x05-Node_JS_basic/full_server/utils.js

@@ -0,0 +1,49 @@
+import fs from 'fs';
+
+/**
+ * Reads the data of students in a CSV data file.
+ * @param {String} dataPath The path to the CSV data file.
+ * @author Bezaleel Olakunori <https://github.com/B3zaleel>
+ * @returns {Promise<{
+ *   String: {firstname: String, lastname: String, age: number}[]
+ * }>}
+ */
+const readDatabase = (dataPath) => new Promise((resolve, reject) => {
+  if (!dataPath) {
+    reject(new Error('Cannot load the database'));
+  }
+  if (dataPath) {
+    fs.readFile(dataPath, (err, data) => {
+      if (err) {
+        reject(new Error('Cannot load the database'));
+      }
+      if (data) {
+        const fileLines = data
+          .toString('utf-8')
+          .trim()
+          .split('\n');
+        const studentGroups = {};
+        const dbFieldNames = fileLines[0].split(',');
+        const studentPropNames = dbFieldNames
+          .slice(0, dbFieldNames.length - 1);
+
+        for (const line of fileLines.slice(1)) {
+          const studentRecord = line.split(',');
+          const studentPropValues = studentRecord
+            .slice(0, studentRecord.length - 1);
+          const field = studentRecord[studentRecord.length - 1];
+          if (!Object.keys(studentGroups).includes(field)) {
+            studentGroups[field] = [];
+          }
+          const studentEntries = studentPropNames
+            .map((propName, idx) => [propName, studentPropValues[idx]]);
+          studentGroups[field].push(Object.fromEntries(studentEntries));
+        }
+        resolve(studentGroups);
+      }
+    });
+  }
+});
+
+export default readDatabase;
+module.exports = readDatabase;