Merge pull request #240 from CacheControl/almanac-events

Author: CacheControl

CHANGELOG.md

@@ -1,7 +1,8 @@
 #### 6.0. / 2020-12-XX
   * BREAKING CHANGES
     * Private `rule.event` property renamed. Use `rule.getEvent()` to avoid breaking changes in the future.
-    * Engine and Rule events `on('success')`, `on('failure')`, and Rule callbacks `onSuccess` and `onFailure` now honor returned promises; any event handler that returns a promise will be waited upon to resolve before engine execution continues.
+    * Engine and Rule events `on('success')`, `on('failure')`, and Rule callbacks `onSuccess` and `onFailure` now honor returned promises; any event handler that returns a promise will be waited upon to resolve before engine execution continues. (fixes #235)
+    * The 'success-events' fact used to store successful events has been converted to an internal data structure and will no longer appear in the almanac's facts. (fixes #187)
 
 #### 5.3.0 / 2020-12-02
   * Allow facts to have a value of `undefined`

src/almanac.js

@@ -17,6 +17,7 @@ export default class Almanac {
     this.factMap = new Map(factMap)
     this.factResultsCache = new Map() // { cacheKey:  Promise<factValu> }
     this.allowUndefinedFacts = Boolean(options.allowUndefinedFacts)
+    this.successEvents = []
 
     for (const factId in runtimeFacts) {
       let fact
@@ -31,6 +32,21 @@ export default class Almanac {
     }
   }
 
+  /**
+   * Adds a success event
+   * @param {Object} event
+   */
+  addSuccessEvent (event) {
+    this.successEvents.push(event)
+  }
+
+  /**
+   * retrieve successful events
+   */
+  getSuccessEvents () {
+    return this.successEvents
+  }
+
   /**
    * Retrieve fact by id, raising an exception if it DNE
    * @param  {String} factId

src/engine-facts.js

@@ -5,7 +5,6 @@ import Rule from './rule'
 import Operator from './operator'
 import Almanac from './almanac'
 import EventEmitter from 'eventemitter2'
-import { SuccessEventFact } from './engine-facts'
 import defaultOperators from './engine-default-operators'
 import debug from './debug'
 
@@ -192,10 +191,9 @@ class Engine extends EventEmitter {
       return rule.evaluate(almanac).then((ruleResult) => {
         debug(`engine::run ruleResult:${ruleResult.result}`)
         if (ruleResult.result) {
-          return Promise.all([
-            almanac.factValue('success-events', { event: ruleResult.event }),
-            this.emitAsync('success', ruleResult.event, almanac, ruleResult)
-          ]).then(() => this.emitAsync(ruleResult.event.type, ruleResult.event.params, almanac, ruleResult))
+          almanac.addSuccessEvent(ruleResult.event)
+          return this.emitAsync('success', ruleResult.event, almanac, ruleResult)
+            .then(() => this.emitAsync(ruleResult.event.type, ruleResult.event.params, almanac, ruleResult))
         } else {
           return this.emitAsync('failure', ruleResult.event, almanac, ruleResult)
         }
@@ -211,7 +209,6 @@ class Engine extends EventEmitter {
    */
   run (runtimeFacts = {}) {
     debug('engine::run started')
-    runtimeFacts['success-events'] = new Fact('success-events', SuccessEventFact(), { cache: false })
     this.status = RUNNING
     const almanac = new Almanac(this.facts, runtimeFacts, { allowUndefinedFacts: this.allowUndefinedFacts })
     const orderedSets = this.prioritizeRules()
@@ -228,7 +225,7 @@ class Engine extends EventEmitter {
       cursor.then(() => {
         this.status = FINISHED
         debug('engine::run completed')
-        return almanac.factValue('success-events')
+        return almanac.getSuccessEvents()
       }).then(events => {
         resolve({
           events,

src/engine.js

@@ -41,6 +41,17 @@ describe('Almanac', () => {
     })
   })
 
+  describe('addSuccessEvent() / getSuccessEvents()', () => {
+    it('manages success events', () => {
+      const event = {}
+      almanac = new Almanac()
+      expect(almanac.getSuccessEvents()).to.be.empty()
+      almanac.addSuccessEvent(event)
+      expect(almanac.getSuccessEvents()).to.have.a.lengthOf(1)
+      expect(almanac.getSuccessEvents()[0]).to.equal(event)
+    })
+  })
+
   describe('arguments', () => {
     beforeEach(() => {
       const fact = new Fact('foo', async (params, facts) => {