MailPocket/README.md

# Forms Server

An extremely lightweight server written in Go to collect email form submissions. This project provides two independent server implementations:

1. **Batched Write Server**: A dependency-free server that stores emails in a CSV file.
2. **SQLite Server**: A server that uses SQLite for reliable and structured email storage.

Both servers are designed to be simple, efficient, and easy to deploy.

---

## Features

- **Batched Write Server**:
  - No external dependencies.
  - Stores emails in a CSV file (`emails.csv`).
  - Batches writes to reduce disk I/O.
  - Lightweight and minimalistic.

- **SQLite Server**:
  - Uses SQLite for structured and reliable email storage.
  - Prevents duplicate emails with a unique constraint.
  - Easy to query and manage stored emails.
  - Slightly more robust and feature-rich.

---

## Getting Started

### Prerequisites

- Go 1.20 or higher.
- For the SQLite Server, the `modernc.org/sqlite` dependency will be installed automatically.

---

### Running the Servers
1.0 Clone the repository:
   ```bash
   git clone https://github.com/your-username/forms-server.git
   cd forms-server
   ```

2.0 Using the Makefile:  
   - ```bash
   	 make run-batched # for CSV-based
   	 ```
   - ```bash
	 make run-sqlite # for SQLite-based
	 ```

2.1 **Batched Write Server**:
   - Navigate to the `batched-server` directory:
     ```bash
     cd batched-server
     ```
   - Run the server manually:
     ```bash
     go run main.go
     ```
   - The server will start on `http://localhost:3000`.

2.2 **SQLite Server**:
   - Navigate to the `sqlite-server` directory:
     ```bash
     cd sqlite-server
     ```
   - Install dependencies (if not already installed):
     ```bash
     go mod tidy
     ```
   - Run the server manually:
     ```bash
     go run main.go
     ```
   - The server will start on `http://localhost:3000`.

---

### API Endpoints

Both servers expose the following endpoints:

- **`GET /`**:
  - Returns a `200 OK` status with a message indicating the server is running.
  - Example response:
    ```json
    "Batched Write Server is running"
    ```

- **`POST /submit`**:
  - Accepts a form submission with an `email` field.
  - Example request:
    ```bash
    curl -X POST -d "email=user@example.com" http://localhost:3000/submit
    ```
  - Example response:
    ```json
    {"message": "data received"}
    ```

---

## Server Implementations

### 1. Batched Write Server (CSV-based)

- **Purpose**: A dependency-free implementation for users who want minimalism and simplicity.
- **Storage**: Emails are appended to a CSV file (`emails.csv`) in the `batched-server` directory.
- **Performance**: Batches writes to reduce disk I/O, flushing every 5 seconds or after 100 emails.
- **Format**: Each row in the CSV file contains an email and a timestamp.
- **Use Case**: Ideal for lightweight deployments where external dependencies are not desired.

### 2. SQLite Server

- **Purpose**: A more robust implementation using SQLite for structured storage.
- **Storage**: Emails are stored in an SQLite database (`emails.db`) in the `sqlite-server` directory.
- **Features**:
  - Prevents duplicate emails with a unique constraint.
  - Tracks the creation timestamp of each email.
- **Use Case**: Ideal for deployments where data integrity and querying capabilities are important.

---

## Configuration

- **Port**: Both servers run on port `3000` by default. To change the port, modify the `PORT` constant in the respective `main.go` file.
- **Storage Location**:
  - Batched Write Server: Emails are stored in `batched-server/emails.csv`.
  - SQLite Server: Emails are stored in `sqlite-server/emails.db`.

---

## Trade-offs

| Feature                | Batched Write Server (CSV)  | SQLite Server               |
|------------------------|------------------------------|-----------------------------|
| **Dependencies**       | None                        | Requires SQLite dependency  |
| **Storage**            | CSV file                    | SQLite database             |
| **Data Integrity**     | Basic                       | High (prevents duplicates)  |
| **Querying**           | Not supported               | Supported                   |
| **Performance**        | High (batched writes)       | High (SQLite optimized)     |
| **Use Case**           | Minimalist, dependency-free | Robust, structured storage  |

---

## Contributing

Contributions are welcome! Please open an issue or submit a pull request for any improvements or bug fixes.

---

## License

This project is licensed under the MIT License. See the [LICENSE](LICENSE) file for details.