# fast-key-generator
##### Simple utils library for API calls.
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---

# Instalation
##### To install `fast-key-generator` - you can use `npm` or `yarn` package manager.
```bash
npm install fast-key-generator --save
```
```bash
yarn add fast-key-generator
```

---

# Documentation
The `fast-key-generator` library includes only one function `generateKey`.
Below you can find the documentation for this function.

---

## The `generateKey` function
##### The simple method for key generation.
##### The `generateKey` function takes only one parameter, which is an object.
##### The `options` parameter may includes the following fields:
| Name      | Type               | Default value  | Description |
| --------- | ------------------ | -------------- | ----------- |
| size      | number             | 16             | Key size (without prefix). |
| prefix    | string             | ""             | Key prefix. |
| chartype  | string             | "alpha"        | Can be one of "alpha", "numeric", "alphanum", "symbols". |
| chartset  | string             | ""             | If you provide `charset`, then the generator will use the characters from this charset & ignore the chartype. |
| transform | string or function | "none"         | Can be one of "none", "lower", "upper" or custom function that takes a key as the first argument & should return formatted key. |
| validate  | function           | empty function | If the function returns true, the generation process will be completed. If false, the generation process will start again until the function returns true. |
| exclude   | array of strings   | []             | An array of strings that should not be keys. |

---

# Examples
```js
import { generateKey } from 'fast-key-generator';

const key = generateKey();
// The key will be a string with a length of 16

```

---

```js
import { generateKey } from 'fast-key-generator';

const key = generateKey({
  size: 1,
  prefix: 'key_',
  chartype: 'numeric',
  exclude: [
    'key_0',
    'key_1',
    'key_2',
    'key_3',
    'key_4',
    'key_5',
    'key_6',
    'key_7',
    'key_8',
  ]
});

// The key will be "key_9"

```

---

```js
import { generateKey } from 'fast-key-generator';

const key = generateKey({
  size: 1,
  prefix: 'key_',
  chartype: 'numeric',
  validate: (key) => key.includes('2')
});

// The key will be "key_2"
```