Access values inside RxJS Observables as if they were directly available on the stream!
stream.pipe(pluck('msg')).subscribe(…);
// turn ↑ into ↓
stream.msg.subscribe(…);
With good TypeScript support!
proxify( Observable<{ msg: string }> ) ≈ Observable<{ msg: string }> & { msg: Observable<string> }
But recursively. So stream.msg
is a Proxy itself, allowing you to stream.msg.length.subscribe(…)
!
Proxify lets you access Observable API as well as pluck props and call methods at any depth of an Observable, Subject, or BehaviorSubject! See the API and Examples sections to learn more.
📦 Install
npm i rxjs-proxify
or try it online!
🛠 API
There are two methods available to you: proxify
and statify
Proxify
proxify(stream)
will wrap your Observable, Subject or BehaviorSubject in a Proxy:
Observable Proxy
subscribe at any depth
const observable = proxify( of({ p: '🐑' }) );
observable.subscribe(console.log); // > { p: 🐑 }
observable.p.subscribe(console.log); // > 🐑
Subject Proxy
subscribe at any depth, push at the root
const subject = proxify(new Subject<{ p: string }>());
subject.subscribe(console.log);
subject.p.subscribe(console.log);
subject.next({ p: '🐥' }); // > { p: 🐥 } // > 🐥
BehaviorSubject Proxy
subscribe at any depth, push at any depth, synchronously read the current state
const behavior = proxify(new BehaviorSubject({ p: '🐖' }));
behavior.p.subscribe(console.log); // > 🐖
behavior.p.next('🐇'); // > 🐇
console.log(behavior.p.value) // > 🐇
Statify
statify(value)
will put the value in a BehaviorSubject Proxy and add a distinctUntilChanged
operator on each property access.
State Proxy
subscribe to distinct updates at any depth, push at any depth, synchronously read the current state
// create a state
const state = statify({ a: '🐰', z: '🏡' });
// listen to & log root state changes
state.subscribe(console.log); //> { a:🐰 z:🏡 }
// update particular substate
state.a.next('🐇'); //> { a:🐇 z:🏡 }
// read current values
console.log(state.z.value + state.a.value); //> 🏡🐇
// update root state, still logging
state.next({ a: '🐇', z: '☁️' }) //> { a:🐇 z:☁️ }
// and then…
state.z.next('🌙'); //> { a:🐇 z:🌙 }
state.a.next('🐇👀'); //> { a:🐇👀 z:🌙 }
state.z.next('🛸') //> { a:🐇👀 z:🛸 }
state.a.next('💨'); //> { a:💨 z:🛸 }
See Examples section for more details.
📖 Examples
Basic
import { proxify } from "rxjs-proxify";
import { of } from "rxjs";
const o = of({ msg: 'Hello' }, { msg: 'World' });
const p = proxify(o);
p.msg.subscribe(console.log);
// equivalent to
// o.pipe(pluck('msg')).subscribe(console.log);
With JS destructuring
Convenient stream props splitting
import { proxify } from "rxjs-proxify";
import { of } from "rxjs";
const o = of({ msg: 'Hello', status: 'ok' }, { msg: 'World', status: 'ok' });
const { msg, status } = proxify(o);
msg.subscribe(console.log);
status.subscribe(console.log);
// equivalent to
// const msg = o.pipe(pluck('msg'));
// const status = o.pipe(pluck('status'));
// msg.subscribe(console.log);
// status.subscribe(console.log);
proxify
, e.g. with shareReplay
:
const { msg, status } = proxify(o.pipe(shareReplay(1)));
With pipe
Concatenate all messages using pipe
with scan
operator:
import { proxify } from "rxjs-proxify";
import { of } from "rxjs";
import { scan } from "rxjs/operators";
const o = of({ msg: 'Hello' }, { msg: 'World' });
const p = proxify(o);
p.msg.pipe(scan((a,c)=> a + c)).subscribe(console.log);
// equivalent to
// o.pipe(pluck('msg'), scan((a,c)=> a + c)).subscribe(console.log);
Calling methods
Pick a method and call it:
import { proxify } from "rxjs-proxify";
import { of } from "rxjs";
const o = of({ msg: () => 'Hello' }, { msg: () => 'World' });
const p = proxify(o);
p.msg().subscribe(console.log);
// equivalent to
// o.pipe(map(x => x?.map())).subscribe(console.log);
Accessing array values
Proxify is recursive, so you can keep chaining props or indices
import { proxify } from "rxjs-proxify";
import { of } from "rxjs";
const o = of({ msg: () => ['Hello'] }, { msg: () => ['World'] });
const p = proxify(o);
p.msg()[0].subscribe(console.log);
// equivalent to
// o.pipe(map(x => x?.map()), pluck(0)).subscribe(console.log);
🤝 Want to contribute to this project?
That will be awesome!
Please create an issue before submiting a PR — we'll be able to discuss it first!
Thanks!