diff --git a/index.ts b/index.ts new file mode 100644 index 0000000..bb83a70 --- /dev/null +++ b/index.ts @@ -0,0 +1,156 @@ +type RequestType = { + method: string; + host: string; + path: string; + body?: User; + params?: { + [key: string]: string; + } +} + +type ObserverHandlers = { + next: (value: RequestType) => void; + error: (error: Error) => void; + complete: () => void; +} + +class Observer { + private handlers: ObserverHandlers; + private isUnsubscribed: boolean; + _unsubscribe: () => void; + + constructor(handlers: ObserverHandlers) { + this.handlers = handlers; + this.isUnsubscribed = false; + } + + next(value: RequestType) { + if (this.handlers.next && !this.isUnsubscribed) { + this.handlers.next(value); + } + } + + error(error: Error) { + if (!this.isUnsubscribed) { + if (this.handlers.error) { + this.handlers.error(error); + } + + this.unsubscribe(); + } + } + + complete() { + if (!this.isUnsubscribed) { + if (this.handlers.complete) { + this.handlers.complete(); + } + + this.unsubscribe(); + } + } + + unsubscribe() { + this.isUnsubscribed = true; + + if (this._unsubscribe) { + this._unsubscribe(); + } + } +} + +class Observable { + private _subscribe: (observer: Observer) => () => void; + + constructor(subscribe: (observer: Observer) => () => void) { + this._subscribe = subscribe; + } + + static from(values: RequestType[]) { + return new Observable((observer: Observer) => { + values.forEach((value: RequestType) => observer.next(value)); + + observer.complete(); + + return () => { + console.log('unsubscribed'); + }; + }); + } + + subscribe(obs: ObserverHandlers) { + const observer = new Observer(obs); + + observer._unsubscribe = this._subscribe(observer); + + return ({ + unsubscribe() { + observer.unsubscribe(); + } + }); + } +} + +const HTTP_POST_METHOD = 'POST'; +const HTTP_GET_METHOD = 'GET'; + +const HTTP_STATUS_OK = 200; +const HTTP_STATUS_INTERNAL_SERVER_ERROR = 500; + +type User = { + name: string; + age: number; + roles: string[]; + createdAt: Date; + isDeleated: boolean; +} + +const userMock: User = { + name: 'User Name', + age: 26, + roles: [ + 'user', + 'admin' + ], + createdAt: new Date(), + isDeleated: false, +}; + +const requestsMock: RequestType[] = [ + { + method: HTTP_POST_METHOD, + host: 'service.example', + path: 'user', + body: userMock, + params: {}, + }, + { + method: HTTP_GET_METHOD, + host: 'service.example', + path: 'user', + params: { + id: '3f5h67s4s' + }, + } +]; + +const handleRequest = (request: RequestType) => { + // handling of request + return {status: HTTP_STATUS_OK}; +}; +const handleError = (error: Error) => { + // handling of error + return {status: HTTP_STATUS_INTERNAL_SERVER_ERROR}; +}; + +const handleComplete = () => console.log('complete'); + +const requests$ = Observable.from(requestsMock); + +const subscription = requests$.subscribe({ + next: handleRequest, + error: handleError, + complete: handleComplete +}); + +subscription.unsubscribe();