pl-decorator v1.4.28

Welcome to pl-decorator

pl-decorator is a collection of decorator that support developer to develop solutions in low time expend

Installation

Install pl-decorator with npm

npm install pl-decorator

Features

In this version, there are very utility for decorate class, properties, attribute of class and other

Decorator Class:

• @Singleton()

• @Injectable()

Decorator method:

• @Log(mode: "log" | "debug" | "info" | "warn" = "log")

• @TryCatch(errorHandle: new () => ErrorHandle)

• @Delay(milliseconds)

Decorator for attribute class:

• @FormatDate(format: string = "DD/MM/yyyy HH: mm: ss", localeId = "it")

• @FormatNumber(format: string | string[] = FORMAT_NUMBER.IT, options?: Intl.NumberFormatOptions)

• @Inject(type:Class)

• @Unsubscribe(ignore = [])

Usage/Examples

@Unsubscribe(ignore = [])

We know very well that RXJS objects are indispensable for Angular and non-Angular applications, but at the same time they are very dangerous, if not destroyed, they could saturate the memory, so that their life cycle does not end with the destruction of a class.
These must be cleared manually or with custom automation.
For this occasion it is possible to create a classy decorator.

@Component({
	selector: 'app-home',
	templateUrl: './home.component.html',
	styleUrls: ['./home.component.css'],
	providers:[HomeService]
})

@Unsubscribe([])

export class HomeComponent implements OnInit {
	/**declaration property observe */
	private testObserve:BehaviorSubject <any> = new BehaviorSubject<any>(null);
	/*********************************************************************** **** */
	/** print variable value */
	ngOnInit() {
		/**listen testObserve for next event, and print received value */
		this.testObserve.subscribe(value => {
		console.log(value);
	}
)

@Log

This annotation takes care of wrapping the annotated function and inserting the start and end function log. The logs report both the input parameters and the return value, in case the function returns a value

import { Log } from  "pl-decorator"

export  class  Test {
 
    public  time:Date = null;
    
    constructor() {
    
	    this.time=new  Date()
    
    }
   
    @Log()
    
	    getDate() {
	    
		    return  this.time
	    
	    }

}

@TryCatch()

This annotation wrap method adding tye catch block and centralize all throws of exception in HandlerError. The annotation receives in input any class that implements the herrorhandler interface in order to then pass the result of the encountered exception, thus centralizing the handling of errors.

@Singleton

export  class  MyErrorHandler  implements  ErrorHandle {

	constructor() { 	}

	handleError(error: Error, propertyKey: string) {
		console.log(`Exception from method ${propertyKey}`);
	}

}



export  class  Test {
		public  time: string = "";
		constructor() { }

	@TryCatch(MyErrorHandler)
	throwExceptionTest(n) {
		throw  new  Error("a")
	}
}

@Singleton

This annotation implement singleton pattern for class. By annotating a class with this annotation, at the time of construction of the class, its previously created instance is returned, if it is not available, a new class is created and the instance is saved to make it available later.

@Singleton

export  class  MyErrorHandler  implements  ErrorHandle {

	constructor() { }

	handleError(error: Error, propertyKey: string) {

	console.log(`Exception from method ${propertyKey}`);

	}

}

  

@FormatDate

This annotation is responsible for formatting date how we prefer. The allowed values are calculated according to this format.

1. YYYY: 4-digit year '2019'

2. YY: 2-digit year '19'

3. MMMM: Full-length month 'June'

4. MMM: 3 character month 'Jun'

5. MM: Month of the year, zero-padded '06'

6. M: Month of the year '6'

7. DD: Day of the month, zero-padded '01'

8. D: Day of the month '1'

9. Do: Day of the month with numeric ordinal contraction '1st'

10. HH: hour of day from 0-24, zero-padded, '14'

11. H: hour of day from 0-24, '14'

12. hh: hour of day on 12-hour clock, zero-padded, '02'

13. h: hour of the day on 12 hour clock, '2'

14. mm: minute, zero-padded, '04'

15. m: minute, '4'

16. ss: second, zero-padded

17. s: second

18. A: 'AM' or 'PM'

19. a: 'am' or 'pm'

export  class  Test {

@FormatDate("HH:mm:ss a")

public  time: Date = null;

constructor() { this.time=new  Date()}

getTime() {

	return  this.time;

}

}

@FormatNumber

This annotation is responsible for formatting number how we prefer, by currency or other, for example

export  class  Test {

	@FormatNumber(FORMAT_NUMBER.DE, {
		style:  'currency',
		currency:  'GBP'
	})
	public  value= 123234345334454;

	constructor() { }

	getValue() {

		return  this.value;
		}

	}

When we print value of variable, it's formatted with DE, and GBP currency.. this is optional, in casi default is IT

@Delay

This annotation is responsible for scedue execution function, it's run at time in input

export  class  Test {

public  time: Date = null;

constructor() { this.time=new  Date()}

@Delay(5000)

	getTime() {

		return  this.time;

	}

}

for call method getTime(), is necessary run with await declaration,

public async method() {
	let t1 = new Test();
	let response = await t1.getTime();
	console.log(response);
}

@Injectable @Inject

These annotations must be placed one on the class to be made injectable and one on the class attribute, where the class declared in the same annotation will be injected. The class will be injected only if it is marked @Injectable, otherwise an error will be thrown indicating that the class cannot be injected.

@Injectable

export  class  Test {

	public  time: Date = null;

	constructor() { this.time=new  Date()}

	getTime() {

		return  this.time;

	}

}


@Injectable
export  class  Test2 {

	@Inject(Test1) test1:Test1;

	console.log(this.test1.time);

	public  time: Date = null;

	constructor() { this.time=new  Date()}

	getTime() {

		return  this.time;

	}
}

export  class  main {

@Inject(Test1) test1:Test1;

@Inject(Test2) test2:Test2;


console.log(this.test2.time);
console.log(this.test1.time);

//in this case, test1 will be created at runtime with injection system because test1 is marked Inject(..) in Test2 class
console.log(this.test2.test1.time);

}

  

All properties marked with @Inject(...) are created automatically and wil be in singleton mode

  

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## Authors

  

- @l.piciollo