docker / getting-started

Node.js Web Application Structure

This outline details the structure of the Node.js web application used in the getting-started repository.

Application Entry Point (server.js)

The application entry point is server.js [server.js]. This file:

  1. Sets up the Express Server: Creates an instance of the Express application (app).
  2. Configures Middleware: Includes middleware such as morgan for logging and bodyParser for parsing request bodies.
  3. Defines Routes: Contains the application’s routes defined using Express routing mechanisms.
  4. Starts the Server: Starts the server and listens on the specified port.

Routing (routes.js)

The routes.js file [routes.js] handles route definitions and requests to the application.

  1. Route Definitions: Defines routes using the app.get and app.post methods for various URLs.
  2. Controller Calls: Executes functions from controllers to handle specific requests.

Controllers (controllers)

The controllers directory [tree/master/controllers] contains functions that handle specific actions and logic related to the application’s routes. Examples include:

  1. index.js: Contains the getHomePage function that renders the home page.
  2. todo.js: Contains functions to:
    • addTodo: Adds a new todo item.
    • getTodos: Retrieves all todo items.
    • deleteTodo: Deletes a specific todo item.

Data Persistence (db.js)

The db.js file [db.js] handles data persistence using sqlite3.

  1. Database Connection: Establishes a connection to the SQLite database.
  2. Data Operations: Implements functions for:
    • getTodos: Retrieves all todo items.
    • addTodo: Adds a new todo item.
    • deleteTodo: Deletes a specific todo item.

Application Logic

The application uses a combination of Express routing and database operations to provide the following functionalities:

  1. Home Page: Displays a welcome message and links to the todo list.
  2. Todo List: Displays a list of todo items with options to add new items and delete existing items.
  3. Data Persistence: Saves and retrieves todo items using the SQLite database.

Example Usage

Adding a new todo item:

curl -X POST http://localhost:3000/todos -d '{"todo": "New Todo Item"}'

Retrieving all todo items:

curl http://localhost:3000/todos

Deleting a todo item:

curl -X DELETE http://localhost:3000/todos/1

Error Handling

The application includes basic error handling using try...catch blocks within controller functions.

Deployment

The application can be deployed using Docker by building and running the Docker image provided in the repository.

Conclusion

This outline provides a summary of the Node.js web application’s structure and functionalities. The code is designed to be simple and demonstrate basic web application development with Node.js, Express, and SQLite.