Local Development Setup

Relevant source files

The following files were used as context for generating this wiki page:

• package.json
• APP/config/db.config.js
• server.js
• APP/models/model.model.js
• seed.js
• public/index.html
• APP/models/index.js

This document outlines the necessary steps and components to set up and run the LostData project on a local development machine. The project is a full-stack application consisting of a Node.js/Express backend, a MongoDB database, and a vanilla JavaScript frontend. It serves as a database for "models," allowing for CRUD operations, data import/export, and role-based access control.

The core of the application is an Express server that provides a REST API for managing model data. The frontend is a single-page application that consumes this API to display and interact with the data. Data persistence is handled by a MongoDB database, with a Mongoose schema defining the data structure.

Architecture Overview

The local development environment consists of three main components: the Frontend Client, the Backend Server, and the Database.

This diagram shows the basic interaction flow: the frontend makes API calls to the Express server, which in turn communicates with the MongoDB database to perform data operations.
Sources: server.js, public/index.html, APP/models/index.js

Prerequisites and Dependencies

To run the project, a Node.js environment and a running MongoDB instance are required. The necessary Node.js packages are listed in package.json.

Dependency	Purpose
express	Web framework for Node.js, used to build the server and API.
mongoose	MongoDB object modeling tool for Node.js.
cors	Middleware to enable Cross-Origin Resource Sharing.
dotenv	Loads environment variables from a .env file.
express-session	Middleware for managing user sessions (used for login).
multer	Middleware for handling multipart/form-data, used for file uploads.
csv-parser	Parses CSV files, used for the import feature.
json2csv	Converts JSON to CSV, used for the export feature.

Sources: package.json:2-10

Install these dependencies using a package manager:

npm install

Configuration

The application requires environment variables for configuration, which can be placed in a .env file at the root of the project.

Variable	Description	Default Value
MONGODB_URI	The connection string for the MongoDB database.	mongodb://127.0.0.1:27017/model_db
PORT	The port on which the Express server will listen.	3000

Sources: server.js:1, 26, 143, APP/config/db.config.js:2

Example .env file:

MONGODB_URI=mongodb://127.0.0.1:27017/model_db
PORT=3000

Database Setup

The application uses MongoDB for data storage. The connection is managed by Mongoose.

Sources: server.js:25-26, APP/models/index.js, APP/config/db.config.js

Model Schema

The data is structured according to the Model schema defined in Mongoose. This schema includes fields for model information, pricing, and an automatically updated history of changes.

The diagram above illustrates the fields and types for the Model collection in the database.

Sources: APP/models/model.model.js:2-15

The schema fields are detailed below:

Field	Type	Constraints	Description
id	String	required, unique	A unique identifier for the model.
name	String	required	The name of the model.
age	Number	-	The age of the model.
location	String	-	The location of the model.
profile	String	required	A detailed profile description.
pricing	String	required	Pricing information.
dosAndDonts	String	required	A list of allowed and disallowed activities.
extraTabs	Array	default: []	An array for additional information tabs.
history	Array	default: []	An audit log of changes made to the record. Automatically updated on save.
createdAt	Date	(timestamps: true)	Timestamp of when the document was created.
updatedAt	Date	(timestamps: true)	Timestamp of the last update.

Sources: APP/models/model.model.js:4-16

A pre-save hook automatically populates the history array with changes whenever an existing document is modified.
Sources: APP/models/model.model.js:18-27

Data Seeding

The seed.js script can be used to populate the database with initial model data. It connects to the MongoDB instance specified in the configuration and inserts a predefined set of model records.

This flowchart shows the execution process of the seed.js script.

To run the seeder:

node seed.js

Sources: seed.js

Running the Application

Once dependencies are installed and the environment is configured, start the server from the project root:

node server.js

The server will perform the following actions on startup:

1. Load environment variables from .env.
2. Connect to the MongoDB database.
3. Set up Express middleware for CORS, JSON parsing, URL encoding, and sessions.
4. Define API routes for login, logout, and model CRUD operations.
5. Serve static files from the public directory.
6. Listen for incoming requests on the configured PORT.

Upon successful startup, you will see DB connected and Server on [PORT] logged to the console. You can then access the application in your browser at http://localhost:3000.

Sources: server.js:1-29, 140-144

API Endpoints

The server.js file defines a RESTful API for interacting with the model data. Access to modification endpoints (POST, PUT, DELETE) and data export is restricted to admin users.

Authentication

• POST /api/login: Logs a user in. An email ending in @admin.com grants 'admin' role, otherwise 'chatter' role. The role is stored in the session.
• POST /api/logout: Destroys the user session.

Sources: server.js:28-41

Model API

The following diagram shows the sequence for fetching all models.

Method	Path	Admin	Description
GET	/api/models	No	Retrieves a sorted list of all models.
GET	/api/models/:id	No	Retrieves a single model by its _id.
POST	/api/models	Yes	Creates a new model.
PUT	/api/models/:id	Yes	Updates an existing model by its _id.
DELETE	/api/models/:id	Yes	Deletes a model by its _id.
GET	/api/export/json	Yes	Exports all models as a JSON file.
GET	/api/export/csv	Yes	Exports all models as a CSV file.
POST	/api/import/csv	Yes	Imports models from an uploaded CSV file.

Sources: server.js:50-132