spyne/src/spyne/utils/viewstream-observables.js

Reactive Real-DOM Framework for Advanced Javascript applications

import { Subject } from 'rxjs'
import { filter, map } from 'rxjs/operators'
import { flip, mergeRight, clone, forEach, propSatisfies } from 'ramda'
export class ViewStreamObservable {
  constructor(props) {
    /**
     * @module ViewStreamObservable
     * @type internal
     *
     * @constructor
     * @desc
     * Internal observable that creates the ViewStream Observable that branches out to parent, internal and child directions
     */
    this.props.observableStreams = ViewStreamObservable.createDirectionalObservables()
  }

  static createDirectionalFiltersObject() {
    const dirInternal = 'internal'
    const dirParent = 'parent'
    const dirChild = 'child'
    return {
      P: [dirParent],
      C: [dirChild],
      PCI: [dirParent, dirInternal, dirChild],
      CI: [dirChild, dirInternal],
      PI: [dirParent, dirInternal],
      PC: [dirParent, dirChild]
    }
  }

  static addDefaultDir(obj) {
    const defaults = flip(mergeRight)
    return defaults({ $dir:['internal'] }, clone(obj))
  }

  static addDownInternalDir(obj, arr = ['internal', 'down']) {
    const defaults = flip(mergeRight)
    return defaults(clone(obj), { $dir:arr })
  }

  static addChildAndInternalDir(obj, arr = ['child', 'down']) {
    const defaults = flip(mergeRight)
    return defaults(clone(obj), { $dir:arr })
  }

  static mapToDefaultDir(p) {
    return this.addDefaultDir(p)
  }

  static createDirectionalObservables(obs$ = new Subject(), viewName, vsid) {
    if (viewName !== undefined && vsid !== undefined) {
      obs$.viewName = viewName
      obs$.vsid = vsid
    }

    const filterStreams = val => propSatisfies(arrType => arrType.includes(val), '$dir')
    const filterParent = filterStreams('parent')
    const filterChild = filterStreams('child')
    const filterInternal = filterStreams('internal')

    const addfrom$ = relStr => mergeRight({ from$:relStr })
    const addParentfrom$ = addfrom$('child')
    const addInternalfrom$ = addfrom$('internal')
    const addChildfrom$ = addfrom$('parent')

    const raw$ =  obs$
      .pipe(filter((payload) => payload !== undefined && payload.action !== undefined))

    const toInternal$ = obs$.pipe(filter(filterInternal), map(addInternalfrom$))
    const toParent$ = obs$.pipe(filter(filterParent), map(addParentfrom$))
    const toChild$ = obs$.pipe(filter(filterChild), map(addChildfrom$))

    const streamObj = {
      parent: toParent$,
      internal: toInternal$,
      child: toChild$
    }

    const completeStream = (arr = []) => {
      const endStream = o => {
        o.complete()
        o.isStopped = true
      }

      const setCompleteStream = (str) => {
        if (streamObj[str] !== undefined) {
          const obs$ = streamObj[str]
          endStream(obs$)
        }
      }

      if (arr !== undefined && arr.length >= 1) {
        arr.forEach(setCompleteStream)
      }
    }
    const completeAll = () => {
      const completeStream = o => {
        o.complete()
        o.isStopped = true
      }
      forEach(completeStream, [raw$, toInternal$, toParent$, toChild$])
    }

    return {
      raw$, toInternal$, toParent$, toChild$, completeAll, completeStream
    }
  }
}