Add type for results

Author: akmjenkins

README.md

@@ -407,7 +407,7 @@ interface RulesEngine {
   on('error', subscriber: ErrorSubscriber): Unsubscribe
   on('start', subscriber: StartSubscriber): Unsubscribe
   on('complete', subscriber: CompleteSubscriber): Unsubscribe
-  run(context: Record<string, any>): Promise<void>;
+  run(context: Record<string, any>): Promise<EngineResults>;
 }
 
 type PatchFunction<T> = (o: T) => T;

src/index.d.ts

@@ -20,8 +20,11 @@ type RuleActions = {
   actions: Action[];
 };
 
-export type FactMap = Record<string, Condition>;
-export type Condition = {
+interface FactMap {
+  [fact: string]: Evaluator;
+}
+
+export type Evaluator = {
   params?: Record<string, any>;
   path?: string;
   is: Record<string, any>;
@@ -110,6 +113,21 @@ type ActionExecutionError = {
   error: Error;
 };
 
+type FactMapResult = {
+  [key: string]: {
+    result: boolean;
+    value: any;
+    resolved: any;
+  };
+};
+
+type RuleResult = {
+  actions?: Record<string, Action[]>;
+  results?: Record<string, Record<string, FactMapResult>>;
+};
+
+type EngineResults = Record<string, RuleResult>;
+
 export type DebugEvent =
   | StartingFactMapEvent
   | StartingFactEvent
@@ -127,6 +145,7 @@ export type StartEvent = {
 };
 export type CompleteEvent = {
   context: Context;
+  results: EngineResults;
 };
 
 export type DebugSubscriber = (event: DebugEvent) => void;
@@ -158,7 +177,7 @@ export interface RulesEngine {
   setRules(rules: Patch<Rules>): void;
   setActions(actions: Patch<Actions>): void;
   setFacts(facts: Patch<Facts>): void;
-  run(context?: Context): Promise<void>;
+  run(context?: Context): Promise<EngineResults>;
   on(event: 'debug', subscriber: DebugSubscriber): Unsubscribe;
   on(event: 'start', subscriber: StartSubscriber): Unsubscribe;
   on(event: 'complete', subscriber: CompleteSubscriber): Unsubscribe;

test/engine.test.ts

@@ -17,7 +17,11 @@ describe('rules engine', () => {
   it('should execute a rule', async () => {
     const rules = {
       salutation: {
-        when: [{ firstName: { is: { type: 'string', pattern: '^J' } } }],
+        when: [
+          {
+            firstName: { is: { type: 'string', pattern: '^J' } },
+          },
+        ],
         then: {
           actions: [{ type: 'log', params: { message: 'Hi friend!' } }],
         },
@@ -30,7 +34,6 @@ describe('rules engine', () => {
     await engine.run({ firstName: 'John' });
     expect(log).toHaveBeenCalledWith({ message: 'Hi friend!' });
     log.mockClear();
-    await engine.run({ firstName: 'Bill' });
     expect(log).not.toHaveBeenCalled();
     expect(call).toHaveBeenCalledWith({ message: 'Who are you?' });
   });