https://github.com/ruben-arushanyan/secure-event-emitter
secure-event-emitter is a tiny javascript package that uses restrict rules and mechanisms to build safer and protected event-driven architecture. It's similar to nodejs EventEmitter, but dictates stricter rules to prevent misuse.
https://github.com/ruben-arushanyan/secure-event-emitter
emit emits emitter event event-emitter eventdispatche eventemitter events handlers javascript listener listeners observer private-event-emitter protected-emitter secure secure-emitter secure-event-emitter trigger
Last synced: about 1 month ago
JSON representation
secure-event-emitter is a tiny javascript package that uses restrict rules and mechanisms to build safer and protected event-driven architecture. It's similar to nodejs EventEmitter, but dictates stricter rules to prevent misuse.
- Host: GitHub
- URL: https://github.com/ruben-arushanyan/secure-event-emitter
- Owner: Ruben-Arushanyan
- License: mit
- Created: 2021-07-26T00:52:18.000Z (almost 4 years ago)
- Default Branch: master
- Last Pushed: 2023-01-03T08:03:24.000Z (over 2 years ago)
- Last Synced: 2025-03-16T10:06:19.819Z (about 1 month ago)
- Topics: emit, emits, emitter, event, event-emitter, eventdispatche, eventemitter, events, handlers, javascript, listener, listeners, observer, private-event-emitter, protected-emitter, secure, secure-emitter, secure-event-emitter, trigger
- Language: JavaScript
- Homepage: https://secure-event-emitter.js.org
- Size: 1.52 MB
- Stars: 13
- Watchers: 1
- Forks: 0
- Open Issues: 5
-
Metadata Files:
- Readme: README.md
- Contributing: CONTRIBUTING.md
- Funding: .github/FUNDING.yml
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
Awesome Lists containing this project
README
# [Secure Event Emitter](https://secure-event-emitter.js.org)
> You can find the full documentation on the
**secure-event-emitter** is a tiny javascript package that uses restrict rules and mechanisms to build safer and protected event-driven architecture. It's similar to nodejs [EventEmitter](https://nodejs.org/api/events.html), but dictates stricter rules to prevent misuse.
## The Main Features
- All event types must be **predefined**․
- Not possible to call the `emit()` method anywhere without the **emitterKey**.
- Ability to **validate** emitted values․
## Installation
```bash
npm install secure-event-emitter
```
## SecureEventEmitter
SecureEventEmitter is the main constructor for creating emitter instances.
#### Import
```js
import {SecureEventEmitter} from 'secure-event-emitter'
```
#### Syntax
#### `new SecureEventEmitter(eventTypes, emitterKey, validator?)`
- **eventTypes** ``
An non-empty array of all event types.
- **emitterKey** `` | ``
Any string or symbol value without which we won't be able to call the `.emit()` method.
- **validator** ``
Function to validate the emitted values․ The function receives the emitted values in the argument and returns an error message if something is wrong there.
#### Usage
```js
import {SecureEventEmitter} from 'secure-event-emitter'
const eventTypes = ['event-1', 'event-2']
const emitterKey = Symbol()
const myEmitter = new SecureEventEmitter(eventTypes, emitterKey)
myEmitter.on('event-1', (a, b) => {
console.log(a, b)
})
myEmitter.on('event-2', (x) => {
console.log(x)
})
myEmitter.unlock(emitterKey).emit('event-1', 2021, 2022)
myEmitter.unlock(emitterKey).emit('event-2', 123)
```
### Validator
We can define a validator function to validate the emitted values.
The function receives the emitted values in the argument and returns an error message if something is wrong there.
#### Example
This example defines a validator function that ensures that the emitter can emit only numbers.
```js
const validator = (x) => {
if (typeof x !== 'number') {
return 'Can emit only numbers!' // error message
}
}
```
#### Usage
```js
import {SecureEventEmitter} from 'secure-event-emitter'
const eventTypes = ['event-1']
const emitterKey = Symbol()
const validator = (x) => {
if (typeof x !== 'number') {
return 'Can emit only numbers!' // error message
}
}
const myEmitter = new SecureEventEmitter(eventTypes, emitterKey, validator)
myEmitter.on('event-1', (a) => {
console.log(a)
})
myEmitter.unlock(emitterKey).emit('event-1', 2021)
myEmitter.unlock(emitterKey).emit('event-1', '2021') // TypeError: Can emit only numbers!
```
## SingularEventEmitter
**SingularEventEmitter** is a special case of **SecureEventEmitter** where each emitter is designed to trigger one type of event․
### basic usage
```js
import {SingularEventEmitter} from 'secure-event-emitter'
// create emitterKey
const emitterKey = Symbol('My Singular Emitter Key')
// create onFoo instance
const onFoo = new SingularEventEmitter(
emitterKey // emitter key is an any Symbol type value
)
// add listeners
onFoo.on((a) => {
// ...
})
onFoo.on((a) => {
// ...
})
onFoo.unlock(emitterKey).emit(2021)
onFoo.unlock(emitterKey).emit(2022)
```
## Payload
**Payload** is a class with which we can create objects that meet certain standards
### basic usage
```js
import {Payload} from 'secure-event-emitter'
// first argument is an origin, can be only symbol type and required
const payload_1 = new Payload(Symbol('My Origin 1'), 1, 2, 3)
// {
// origin: Symbol('My Origin 1'),
// args: [1, 2, 3],
// meta: {
// date: 545125412152,
// _index: 1
// }
// }
const payload_2 = new Payload(Symbol('My Origin 2'), 'a', 'b')
// {
// origin: Symbol('My Origin 2'),
// args: [1, 2, 3],
// meta: {
// date: 54512541999,
// _index: 1
// }
// }
```
## useListener
**useListener** is a helper hook for use emitter in react component
### basic usage
```js
import {useListener} from 'secure-event-emitter/react'
// ...
// ...
useListener(emitter, 'event-type', () => {
// ...
})
// ...
// ...
```
## [Contributing](https://github.com/ruben-arushanyan/secure-event-emitter/blob/master/CONTRIBUTING.md)
Read our [contributing guide](https://github.com/ruben-arushanyan/secure-event-emitter/blob/master/CONTRIBUTING.md) to learn about our development process.
## [Code of Conduct](https://github.com/ruben-arushanyan/secure-event-emitter/blob/master/CODE_OF_CONDUCT.md)
This project has adopted the [Contributor Covenant](https://www.contributor-covenant.org) as its Code of Conduct, and we expect project participants to adhere to it. Please read the [full text](https://github.com/ruben-arushanyan/secure-event-emitter/blob/master/CODE_OF_CONDUCT.md) so that you can understand what actions will and will not be tolerated.
## Authors
- [Ruben Arushanyan](https://github.com/ruben-arushanyan)
## License
[MIT](https://github.com/ruben-arushanyan/secure-event-emitter/blob/master/LICENSE)