@usecomma/modulus-check/README.md

Validate a UK bank account number against a sort code using the VocaLink modulus check

# modulus-check
Modulus checking allows payment originators to confirm that customer codes and account numbers are compatible before submitting a Bacs Direct Credit of Direct Debit.

## Status
[![npm version][npm-image]][npm-url]

## Installation
Install the package via `yarn`:

```sh
yarn add modulus-check
```
or `npm`:
```sh
npm install modulus-check
```

## Usage

### `new ModulusCheck({ accountNumber, sortCode }).isValid()`

This method validates if the given accountNumber and sortCode represent a valid `Faster Payment Account`.

#### Arguments

1. `accountNumber` *(string)*: The account number to validate.
2. `sortCode` *(string)*: The sort code to validate.

#### Returns
*(boolean)*:  Returns `true` if the account is valid.

#### Example
```js
new ModulusCheck({ accountNumber: '15764273', sortCode: '938063' }).isValid();
// => false

new ModulusCheck({ accountNumber: '66374958', sortCode: '089999' }).isValid();
// => true

new ModulusCheck({ accountNumber: '66374958', sortCode: '08-99-99' }).isValid();
// => true

new ModulusCheck({ accountNumber: '66374958', sortCode: '08-9999' }).isValid();
// => true
```

## Tests

```sh
npm test
```

## Release
Run the below command and commit to `master` branch
```sh
npm version [<newversion> | major | minor | patch] -m "Release %s"
```
Head to circelci and trigger a new pipeline with parameter `release: true`

## License
MIT

## Credits
Many thanks to [bazerk/uk-modulus-checking](https://github.com/bazerk/uk-modulus-checking) for the original inspiration and [uphold/uk-modulus-checking](https://github.com/uphold/uk-modulus-checking) for the initial development.

[npm-image]: https://img.shields.io/npm/v/modulus-check.svg?style=flat-square
[npm-url]: https://npmjs.org/package/@usecomma/modulus-check