Function: splitSources()

splitSources<CommonAction, Aliases>(source$, partitions?): { [K in string | number | symbol]: ActionMap<CommonAction>[Aliases[K]] } & ActionMap<CommonAction>

Defined in: libs/rxjs/src/lib/sources/split-sources.function.ts:77

splitSources is a function that takes in an Observable that emits multiple types of Action objects and splits it into a source for each Action type. It takes two arguments:

• source$: Observable<CommonAction>
• aliases?: Aliases extends { [index: string]: CommonType } — An optional object with keys that will become the new source names, and values that will filter against the type property of the actions from the source$ observable.

It returns a proxy object that defines keys from the source types and the aliases argument (if provided), and values of type Observable<Action<Payload, Type>> where Payload and Type are inferred from the filtered CommonAction type.

If the source type is specific (as in 'even$' | 'odd$'), the returned object will have 'even$' and 'odd$' properties. If the source type is just a string, any string can be accessed, and splitSources will filter against that string. The proxy defines this filtered source once the property is accessed.

Example: Splitting a source into multiple sources

import { getAction } from '@state-adapt/core';
import { splitSources } from '@state-adapt/rxjs';
import { interval, map } from 'rxjs';

const evenAndOdd$ = interval(1000).pipe(
  map(n => ({
    // type has to be 'even$' | 'odd$', not just a string
    type: n % 2 === 0 ? ('even$' as const) : ('odd$' as const),
    payload: n,
  })),
);

evenAndOdd$.subscribe(console.log);
// { type: 'even$', payload: 0 }
// { type: 'odd$', payload: 1 }
// { type: 'even$', payload: 2 }
// { type: 'odd$', payload: 3 }

const { even$, odd$ } = splitSources(evenAndOdd$);

even$.subscribe(console.log);
// { type: 'even$', payload: 0 }
// { type: 'even$', payload: 2 }

odd$.subscribe(console.log);
// { type: 'odd$', payload: 1 }
// { type: 'odd$', payload: 3 }

Example: Splitting an HTTP source using aliases

import { getAction } from '@state-adapt/core';
import { toSource, splitSources } from '@state-adapt/rxjs';
import { ajax } from 'rxjs/ajax';

const http$ = ajax('https://jsonplaceholder.typicode.com/todos/1').pipe(
  map(res => ({ type: 'todos.success$' as const, payload: res })),
  catchError(error => of({ type: 'todos.error$' as const, payload: error })),
);

const { success$, error$ } = splitSources(http$, {
  success$: 'todos.success$',
  error$: 'todos.error$',
});

success$.subscribe(console.log);
// { type: 'success$', payload: { ... } }

error$.subscribe(console.log);
// { type: 'error$', payload: { ... } }

Type Parameters

CommonAction

CommonAction extends object

Aliases

Aliases extends object

Parameters

source$

Observable<CommonAction>

partitions?

Aliases

Returns

{ [K in string | number | symbol]: ActionMap<CommonAction>[Aliases[K]] } & ActionMap<CommonAction>