README.md
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# seng-signals
Signal is a Observer Pattern that works on the basis that every event has its own controller, its more clear what a controller dispatches and its hi-performance.
## Installation
### npm
```sh
npm install --save seng-signals
```
### other
We also have browser, amd, commonjs, umd, systemjs and es6 versions of
this module available attached to the [Github Releases](https://github.com/mediamonks/seng-signals/releases).
### manual
Check the **build** section below to see your you can build for all the
targets yourself.
## Usage
```ts
import {Signal, Signal1, Signal2} from 'seng-signals';
var signal = new Signal();
var connection = signal.connect(function(){
console.log('emitted');
});
signal.emit(); // console.log('emitted');
signal.emit(); // console.log('emitted');
signal.emit(); // console.log('emitted');
// -----
connection.dispose();
var signal = new Signal();
var connection = signal.connect(function(){
console.log('emitted');
});
connection.once();
signal.emit(); // console.log('emitted');
signal.emit(); // nothing
signal.emit(); // nothing
// -----
var signal = new Signal1();
var connection = signal.connect(function(value){
console.log('emitted:', value);
});
signal.emit(1); // console.log('emitted:', 1);
signal.emit(2); // console.log('emitted:', 2);
signal.emit(3); // console.log('emitted:', 3);
// -----
var signal = new Signal2();
var connection = signal.connect(function(a, b){
console.log('emitted:', a, b);
});
signal.emit('apple', 1); // console.log('emitted:', 'apple', 1);
signal.emit('pinapple', 2); // console.log('emitted:', 'apple', 1);
connection.dispose();
signal.disconnectAll();
signal.emit('sugar', 3); // nothing
// -----
var signal = new Signal();
signal.connect(function(a, b){
console.log('emitted A');
}).once();
// put this listener on top of all others
signal.connect(function(){
console.log('emitted B');
}, true).once();
signal.emit();
// -----
```
### Usage with Class
This is all hypothetical fetch streaming code, this just gives a example of how to use signals in different setting.
```
class Loader {
constructor(path){
this.path = path;
this.progress = new Signal1();
this.complete = new Signal();
}
load(){
var _this = this;
fetch(this.path).then(response => {
var reader = response.body.getReader();
var bytesReceived = 0;
var totalBytes = 1000000;
reader.read().then(function processResult(result) {
if (result.done) {
_this.complete.emit();
return;
}
bytesReceived += result.value.length;
_this.progress.emit(bytesReceived/totalBytes);
return reader.read().then(processResult);
});
});
}
}
```
## Documentation
View the [generated documentation](https://rawgit.com/mediamonks/seng-signals/master/doc/typedoc/index.html).
## Building
In order to build signals, ensure that you have [Git](http://git-scm.com/downloads)
and [Node.js](http://nodejs.org/) installed.
Clone a copy of the repo:
```sh
git clone https://github.com/mediamonks/seng-signals.git
```
Change to the signals directory:
```sh
cd seng-signals
```
Install dev dependencies:
```sh
npm install
```
Use one of the following main scripts:
```sh
npm run build # build this project
npm run dev # run dev-watch mode, seving example/index.html in the browser
npm run generate # generate all artifacts (compiles ts, webpack, docs and coverage)
npm run test-unit # run the unit tests
npm run validate # runs validation scripts, including test, lint and coverage check
npm run lint # run tslint on this project
npm run doc # generate typedoc documentation
npm run typescript-npm # just compile the typescript output used in the npm module
```
When installing this module, it adds a pre-push hook, that runs the `validate`
script before committing, so you can be sure that everything checks out.
If you want to create the distribution files yourself, you can run the
`build-dist` script, and the following files will get generated in the
`dist` folder:
- **/dist/seng-signals.js**: bundled with webpack, can be loaded from
a script tag, available as `window.SengSignals`
- **/dist/seng-signals.min.js**: same as above, but minified
- **/dist/seng-signals-amd.js**: bundled with webpack, can be used
with e.g. requirejs
- **/dist/seng-signals-commonjs.js**: bundled with webpack, can be
used in systems that support commonjs, but you should just use npm
- **/dist/seng-signals-umd.js**: bundled with webpack, works in the
browser, with requirejs, and in a commonjs system
- **/dist/seng-signals-umd.min.js**: same as above, but minified
- **/dist/seng-signals-system.js**: bundled with typescript, can be
used in systems that support systemjs
- **/dist/seng-signals-es6.zip**: transpiled with typescript, only
types are removed from the source files
## Contribute
View [CONTRIBUTING.md](./CONTRIBUTING.md)
## Changelog
View [CHANGELOG.md](./CHANGELOG.md)
## Authors
View [AUTHORS.md](./AUTHORS.md)
## LICENSE
[MIT](./LICENSE)