implement derivedState + derivedParam

README.md

@@ -20,8 +20,22 @@ npm install bottender-recognizer
 (state, event) => intent | undefined
 ```
 
+Example:
+
+```js
+async (state, intent) => ({
+  name: 'INTENT_NAME',
+  payload: {},
+});
+```
+
 ### Intent
 
+* `name` - Must have.
+* `payload` - Recommended.
+
+Example:
+
 ```js
 {
   name: "INTENT_NAME",
@@ -35,12 +49,60 @@ npm install bottender-recognizer
 (state, intent) => action
 ```
 
+Example:
+
+```js
+(state, intent) => doSomething;
+```
+
+With `derivedState` and `derivedParam`:
+
+```
+(state, intent) => derivedState + derivedParam + action
+```
+
+Example:
+
+```js
+(state, intent) => ({
+  action: doSomething,
+  derivedState: {
+    x: 1,
+  },
+  derivedParam: {
+    y: 2,
+  },
+});
+```
+
 ### Action
 
 ```
 context => void
 ```
 
+Example:
+
+```js
+async context => {
+  // ...
+};
+```
+
+With parameters:
+
+```
+context + param => void
+```
+
+Example:
+
+```js
+async (context, param) => {
+  // ...
+};
+```
+
 ## API Reference
 
 ### `createHandler({ recognizer, resolver, chatbase, debug })`

package.json

@@ -20,7 +20,8 @@
   },
   "dependencies": {
     "@google/chatbase": "^1.0.0",
-    "delay": "^2.0.0"
+    "delay": "^2.0.0",
+    "warning": "^3.0.0"
   },
   "devDependencies": {
     "eslint": "^4.13.1",

src/__tests__/index.spec.js

@@ -1,7 +1,23 @@
 const delay = require('delay');
+const warning = require('warning');
 
 const { createHandler, combineRecognizers } = require('../');
 
+jest.mock('warning');
+
+function createContext() {
+  return {
+    state: {},
+    event: {},
+    setState(state) {
+      this.state = {
+        ...this.state,
+        ...state,
+      };
+    },
+  };
+}
+
 it('exports public apis', () => {
   expect(createHandler).toBeDefined();
   expect(combineRecognizers).toBeDefined();
@@ -14,10 +30,7 @@ describe('#combineRecognizers', () => {
       () => Promise.resolve({ name: 'intent' }),
     ]);
 
-    const context = {
-      state: {},
-      event: {},
-    };
+    const context = createContext();
 
     const intent = await recognizers(context.state, context.event);
 
@@ -30,10 +43,7 @@ describe('#combineRecognizers', () => {
       () => Promise.resolve(null),
     ]);
 
-    const context = {
-      state: {},
-      event: {},
-    };
+    const context = createContext();
 
     const intent = await recognizers(context.state, context.event);
 
@@ -46,10 +56,7 @@ describe('#combineRecognizers', () => {
       { timeout: 100 }
     );
 
-    const context = {
-      state: {},
-      event: {},
-    };
+    const context = createContext();
 
     const intent = recognizers(context.state, context.event);
     await Promise.resolve();
@@ -65,10 +72,7 @@ describe('#combineRecognizers', () => {
       { timeout: 500 }
     );
 
-    const context = {
-      state: {},
-      event: {},
-    };
+    const context = createContext();
 
     const intent = recognizers(context.state, context.event);
     await Promise.resolve();
@@ -84,10 +88,7 @@ describe('#createHandler', () => {
     const targetHandler = jest.fn();
     const recognizer = () => Promise.resolve({ name: 'intent' });
     const resolver = () => targetHandler;
-    const context = {
-      state: {},
-      event: {},
-    };
+    const context = createContext();
 
     const handler = createHandler({ recognizer, resolver });
 
@@ -97,4 +98,93 @@ describe('#createHandler', () => {
 
     expect(targetHandler).toBeCalledWith(context, otherArg);
   });
+
+  it('should warning when resolver resolve undefined', async () => {
+    const recognizer = () => Promise.resolve({ name: 'intent' });
+    const resolver = () => {};
+    const context = createContext();
+
+    const handler = createHandler({ recognizer, resolver });
+
+    await handler(context);
+
+    expect(warning).toBeCalled();
+  });
+
+  it('should support derivedState', async () => {
+    const targetHandler = jest.fn();
+    const recognizer = () => Promise.resolve({ name: 'intent' });
+    const resolver = () => ({
+      action: targetHandler,
+      derivedState: {
+        x: 1,
+      },
+    });
+    const context = createContext();
+
+    const handler = createHandler({ recognizer, resolver });
+
+    await handler(context);
+
+    expect(targetHandler.mock.calls[0][0].state).toEqual({
+      x: 1,
+    });
+  });
+
+  describe('derivedParam', () => {
+    it('should warning when second arg is not an object', async () => {
+      const targetHandler = jest.fn();
+      const recognizer = () => Promise.resolve({ name: 'intent' });
+      const resolver = () => ({
+        action: targetHandler,
+        derivedParam: {
+          x: 1,
+        },
+      });
+      const context = createContext();
+
+      const handler = createHandler({ recognizer, resolver });
+
+      await handler(context, 1);
+
+      expect(targetHandler).toBeCalledWith(context, 1);
+      expect(warning).toBeCalled();
+    });
+
+    it('should merge when second arg is an object', async () => {
+      const targetHandler = jest.fn();
+      const recognizer = () => Promise.resolve({ name: 'intent' });
+      const resolver = () => ({
+        action: targetHandler,
+        derivedParam: {
+          x: 1,
+        },
+      });
+      const context = createContext();
+
+      const handler = createHandler({ recognizer, resolver });
+
+      await handler(context, { y: 2 });
+
+      expect(targetHandler).toBeCalledWith(context, { x: 1, y: 2 });
+    });
+
+    it('should provide param when second arg is undefined', async () => {
+      const targetHandler = jest.fn();
+      const recognizer = () => Promise.resolve({ name: 'intent' });
+      const resolver = () => ({
+        action: targetHandler,
+        derivedParam: {
+          x: 1,
+        },
+      });
+      const context = createContext();
+
+      const handler = createHandler({ recognizer, resolver });
+
+      await handler(context);
+
+      expect(targetHandler).toBeCalledWith(context, { x: 1 });
+    });
+  });
 });

src/index.js

@@ -1,4 +1,5 @@
 const delay = require('delay');
+const warning = require('warning');
 
 exports.combineRecognizers = function combineRecognizers(
   recognizers,
@@ -42,7 +43,7 @@ exports.createHandler = function createHandler({
       .setPlatform(chatbase.platform); // The platform you are interacting with the user over
   }
 
-  return async (context, ...otherArgs) => {
+  return async (context, arg, ...otherArgs) => {
     const intent = await recognizer(context.state, context.event);
 
     // log intent to chatbase or other service here
@@ -63,7 +64,27 @@ exports.createHandler = function createHandler({
         .catch(console.error);
     }
 
-    const action = resolver(context.state, intent);
+    const result = resolver(context.state, intent);
+
+    if (
+      !result ||
+      !(typeof result === 'object' || typeof result === 'function')
+    ) {
+      warning(false, 'resolver must return a function or an object.');
+      return;
+    }
+
+    let action;
+    let derivedState;
+    let derivedParam;
+
+    if (typeof result === 'object') {
+      action = result.action;
+      derivedState = result.derivedState;
+      derivedParam = result.derivedParam;
+    } else {
+      action = result;
+    }
 
     if (debug) {
       console.log('Action: ', action.displayName || action.name);
@@ -80,6 +101,26 @@ exports.createHandler = function createHandler({
         .catch(console.error);
     }
 
-    await action(context, ...otherArgs);
+    if (derivedState) {
+      context.setState(derivedState);
+    }
+
+    if (!derivedParam) {
+      await action(context, arg, ...otherArgs);
+      return;
+    }
+    if (arg && typeof arg !== 'object') {
+      warning(
+        false,
+        'should not provide not object type param with derivedParam. derivedParam will not be applied.'
+      );
+      await action(context, arg, ...otherArgs);
+    } else {
+      const param = {
+        ...arg,
+        ...derivedParam,
+      };
+      await action(context, param, ...otherArgs);
+    }
   };
 };

yarn.lock

@@ -3347,6 +3347,12 @@ walker@~1.0.5:
   dependencies:
     makeerror "1.0.x"
 
+warning@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/warning/-/warning-3.0.0.tgz#32e5377cb572de4ab04753bdf8821c01ed605b7c"
+  dependencies:
+    loose-envify "^1.0.0"
+
 watch@~0.18.0:
   version "0.18.0"
   resolved "https://registry.yarnpkg.com/watch/-/watch-0.18.0.tgz#28095476c6df7c90c963138990c0a5423eb4b986"