btc-pay-checker/README.md

# Bitcoin Payment Checker

Bitcoin Payment Checker is a Go application that allows clients to pay for orders using Bitcoin. The application calculates the Bitcoin equivalent of the order amount, provides a wallet address for payment, and tracks the payment status.

## Demo
You can try it here on bitcoin testnet: https://btcpaychecker.urkob.com/

## Application Structure

The application is structured into several packages:

- `handler`: Contains the HTTP handlers for the application. The `OrderHandler` is responsible for processing new orders and calculating the Bitcoin price.
- `services`: Contains various services used by the application, such as the `Order` service for managing orders and the `PriceConversor` service for converting USD to Bitcoin.
- `main`: The entry point of the application. It sets up the database connection, initializes the services, and starts the HTTP server.

## Key Files

- `handler/order.go`: Contains the `OrderHandler` which processes new orders. It calculates the Bitcoin price of the order, stores the order in the database, and renders an HTML page with the order details.
- `main.go`: The entry point of the application. It sets up the database connection, initializes the services, and starts the HTTP server.

## Running the Application

To run the application, you need to have Go installed. Then, you can run the application using the `go run` command:

```bash
go run main.go
```

This will start the application and listen for HTTP requests on the configured port.

## Environment Variables

The application uses the following environment variables:
```
    PAY_CHECKER_ENV: The environment the application is running in. If set to "dev", the application will load configuration from a .env file.
    DB_ADDRESS: The address of the MongoDB database.
    DB_NAME: The name of the MongoDB database.
    ORDERS_COLLECTION: The name of the MongoDB collection for orders.
    CONVERSOR_API: The API used for converting USD to Bitcoin.
    RPC_HOST, RPC_AUTH, RPC_ZMQ, WALLET_ADDRESS: Configuration for the Bitcoin service.
    MAIL_USER, MAIL_PASSWORD, MAIL_HOST, MAIL_PORT, MAIL_FROM, MAIL_TEMPLATES_DIR: Configuration for the mail service.
```    

### Webhook configuration
If you want some http endpoint to be called by **POST** you have to set up `WEBHOOK_URL` as environment variable with absolute URL of your endpoint. After payment is completed by client, order will be send through http `POST`.

## Dependencies

The application uses several external packages:

    gofiber/fiber/v2: For building the HTTP server and handling requests.
    go.mongodb.org/mongo-driver/mongo: For connecting to and interacting with MongoDB.
    net/smtp: For sending emails.