refactored remove rule and added updateRule

Author: ilanskogan

docs/engine.md

@@ -44,6 +44,8 @@ undefined facts as `undefined`. (default: false)
 
 `pathResolver` - Allows a custom object path resolution library to be used. (default: `json-path` syntax). See [custom path resolver](./rules.md#condition-helpers-custom-path-resolver) docs.
 
+`ruleKeyField` - By default this field is set to 'id', this field is the rule property that will be used when removing a rule by a key string or when updating rule
+
 ### engine.addFact(String id, Function [definitionFunc], Object [options])
 
 ```js
@@ -73,6 +75,7 @@ engine.removeFact('speed-of-light')
 ### engine.addRule(Rule instance|Object options)
 
 Adds a rule to the engine. The engine will execute the rule upon the next ```run()```
+if the rule doesn't have value set at rule[engine.ruleKeyField], a random string will be set instead.
 
 ```js
 let Rule = require('json-rules-engine').Rule
@@ -102,6 +105,22 @@ engine.addRule(rule)
 
 //remove it
 engine.removeRule(rule)
+//or
+engine.removeRule(rule.id)
+```
+
+ ### engine.updateRule(Rule instance|Object options)
+
+ Updates a rule in the engine.
+
+```javascript
+// adds a rule
+let rule = new Rule()
+engine.addRule(rule)
+rule.conditions.all = []
+
+//update it
+engine.updateRule(rule)
 ```
 
 ### engine.addOperator(String operatorName, Function evaluateFunc(factValue, jsonValue))

src/engine.js

@@ -25,6 +25,7 @@ class Engine extends EventEmitter {
  this.operators = new Map()
  this.facts = new Map()
  this.status = READY
+ this.ruleKeyField = options.ruleKeyField || 'id'
  rules.map(r => this.addRule(r))
  defaultOperators.map(o => this.addOperator(o))
  }
@@ -47,27 +48,44 @@ class Engine extends EventEmitter {
  } else {
  if (!Object.prototype.hasOwnProperty.call(properties, 'event')) throw new Error('Engine: addRule() argument requires "event" property')
  if (!Object.prototype.hasOwnProperty.call(properties, 'conditions')) throw new Error('Engine: addRule() argument requires "conditions" property')
-
  rule = new Rule(properties)
  }
  rule.setEngine(this)
-
+ if (!rule[this.ruleKeyField]) rule[this.ruleKeyField] = '_' + Math.random().toString(36).substr(2, 9)
  this.rules.push(rule)
  this.prioritizedRules = null
  return this
  }
 
  /**
- * Remove a rule from the engine
+ * update a rule in the engine
  * @param {object|Rule} rule - rule definition. Must be a instance of Rule
  */
- removeRule (rule) {
- if ((rule instanceof Rule) === false) throw new Error('Engine: removeRule() rule must be a instance of Rule')
+ updateRule (rule) {
+ const ruleIndex = this.rules.findIndex(ruleInEngine => ruleInEngine[this.ruleKeyField] === rule[this.ruleKeyField])
+ if (ruleIndex > -1) {
+ this.rules.splice(ruleIndex, 1)
+ this.addRule(rule)
+ } else {
+ throw new Error('Engine: updateRule() rule not found')
+ }
+ }
 
- const index = this.rules.indexOf(rule)
- if (index === -1) return false
- this.prioritizedRules = null
- return Boolean(this.rules.splice(index, 1).length)
+ /**
+ * Remove a rule from the engine
+ * @param {object|Rule||string} rule - rule definition. Must be a instance of Rule
+ */
+ removeRule (rule) {
+ if (!(rule instanceof Rule)) {
+ this.rules = this.rules.filter(ruleInEngine => ruleInEngine[this.ruleKeyField] !== rule)
+ this.prioritizedRules = null
+ return Boolean(this.rules.length)
+ } else {
+ const index = this.rules.indexOf(rule)
+ if (index === -1) return false
+ this.prioritizedRules = null
+ return Boolean(this.rules.splice(index, 1).length)
+ }
  }
 
  /**

test/engine.test.js

@@ -84,6 +84,17 @@ describe('Engine', () => {
  })
  })
 
+ describe('updateRule()', () => {
+ it('updates rule', () => {
+ const rule = new Rule(factories.rule())
+ engine.addRule(rule)
+ expect(engine.rules[0].conditions.all.length).to.equal(2)
+ rule.conditions = { all: [] }
+ engine.updateRule(rule)
+ expect(engine.rules[0].conditions.all.length).to.equal(0)
+ })
+ })
+
  describe('removeRule()', () => {
  describe('rule instance', () => {
  it('removes the rule', () => {
@@ -96,14 +107,6 @@ describe('Engine', () => {
  })
  })
 
- describe('required fields', () => {
- it('.conditions', () => {
- expect(() => {
- engine.removeRule([])
- }).to.throw(/Engine: removeRule\(\) rule must be a instance of Rule/)
- })
- })
-
  it('can only remove added rules', () => {
  expect(engine.rules.length).to.equal(0)
  const rule = new Rule(factories.rule())
@@ -118,6 +121,14 @@ describe('Engine', () => {
  engine.removeRule(rule)
  expect(engine.prioritizedRules).to.equal(null)
  })
+ it('removes rule based on ruleKey', () => {
+ const rule = new Rule(factories.rule())
+ engine.addRule(rule)
+ expect(engine.rules.length).to.equal(1)
+ engine.removeRule(rule.id)
+ expect(engine.rules.length).to.equal(0)
+ expect(engine.prioritizedRules).to.equal(null)
+ })
  })
 
  describe('addOperator()', () => {