partial move to async / await

Author: bertho-zero

api/actions/__tests__/widget-load-test.js

@@ -14,17 +14,15 @@ describe('widget load', () => {
       sinon.stub(Math, 'random').returns(0.4);
     });
 
-    it('uses the widgets from the session', () => {
-      load({ session: { user: {}, widgets: ['a', 'b', 'c'] } }, undefined).then(widgets => {
-        expect(widgets.length).to.equal(3);
-      });
+    it('uses the widgets from the session', async () => {
+      const widgets = await load({ session: { user: {}, widgets: ['a', 'b', 'c'] } }, undefined);
+      expect(widgets.length).to.equal(3);
     });
 
-    it('initializes the widgets ', () => {
-      load({ session: { user: {} } }, undefined).then(widgets => {
-        expect(widgets.length).to.equal(4);
-        expect(widgets[0].color).to.equal('Red');
-      });
+    it('initializes the widgets ', async () => {
+      const widgets = await load({ session: { user: {} } }, undefined);
+      expect(widgets.length).to.equal(4);
+      expect(widgets[0].color).to.equal('Red');
     });
   });
 
@@ -34,12 +32,11 @@ describe('widget load', () => {
     });
 
     it('rejects the call', () => {
-      load({ session: { user: {} } }, undefined).then(
-        () => {},
-        err => {
-          expect(err).to.equal('Widget load fails 33% of the time. You were unlucky.');
-        }
-      );
+      try {
+        load({ session: { user: {} } }, undefined);
+      } catch (err) {
+        expect(err).to.equal('Widget load fails 33% of the time. You were unlucky.');
+      }
     });
   });
 });

api/actions/widget/update.js

@@ -3,29 +3,27 @@ import load from './load';
 export default function update(req) {
   return new Promise((resolve, reject) => {
     // write to database
-    setTimeout(() => {
+    setTimeout(async () => {
       if (Math.random() < 0.2) {
         reject('Oh no! Widget save fails 20% of the time. Try again.');
       } else {
-        load(req).then(
-          data => {
-            const widgets = data;
-            const widget = req.body;
-            if (widget.color === 'Green') {
-              reject({
-                color: 'We do not accept green widgets' // example server-side validation error
-              });
-            }
-            if (widget.id) {
-              widgets[widget.id - 1] = widget; // id is 1-based. please don't code like this in production! :-)
-              req.session.widgets = widgets;
-            }
-            resolve(widget);
-          },
-          err => {
-            reject(err);
+        try {
+          const data = await load(req);
+          const widgets = data;
+          const widget = req.body;
+          if (widget.color === 'Green') {
+            reject({
+              color: 'We do not accept green widgets' // example server-side validation error
+            });
           }
-        );
+          if (widget.id) {
+            widgets[widget.id - 1] = widget; // id is 1-based. please don't code like this in production! :-)
+            req.session.widgets = widgets;
+          }
+          resolve(widget);
+        } catch (err) {
+          reject(err);
+        }
       }
     }, 1500); // simulate async db write
   });

api/api.js

@@ -6,7 +6,6 @@ import cookieParser from 'cookie-parser';
 import hooks from 'feathers-hooks';
 import rest from 'feathers-rest';
 import socketio from 'feathers-socketio';
-import isPromise from 'is-promise';
 import PrettyError from 'pretty-error';
 import config from './config';
 import middleware from './middleware';
@@ -35,37 +34,37 @@ app
   .use(bodyParser.urlencoded({ extended: true }))
   .use(bodyParser.json());
 
-const actionsHandler = (req, res, next) => {
-  const splittedUrlPath = req.url.split('?')[0].split('/').slice(1);
+const actionsHandler = async (req, res, next) => {
+  const splittedUrlPath = req.url
+    .split('?')[0]
+    .split('/')
+    .slice(1);
   const { action, params } = mapUrl(actions, splittedUrlPath);
 
   req.app = app;
 
-  const catchError = error => {
+  const catchError = async error => {
     console.error('API ERROR:', pretty.render(error));
     res.status(error.status || 500).json(error);
   };
 
   if (action) {
     try {
-      const handle = action(req, params);
-      (isPromise(handle) ? handle : Promise.resolve(handle))
-        .then(result => {
-          if (result instanceof Function) {
-            result(res);
-          } else {
-            res.json(result);
-          }
-        })
-        .catch(reason => {
-          if (reason && reason.redirect) {
-            res.redirect(reason.redirect);
-          } else {
-            catchError(reason);
-          }
-        });
+      try {
+        const result = await action(req, params);
+        if (result instanceof Function) {
+          result(res);
+        } else {
+          res.json(result);
+        }
+      } catch (reason) {
+        if (reason && reason.redirect) {
+          return res.redirect(reason.redirect);
+        }
+        return catchError(reason);
+      }
     } catch (error) {
-      catchError(error);
+      return catchError(error);
     }
   } else {
     next();

api/hooks/validateHook.js

@@ -2,10 +2,14 @@ import errors from 'feathers-errors';
 import { createAsyncValidator as validator } from 'utils/validation';
 
 export default function validateHook(schema) {
-  return hook =>
-    validator(schema, { hook })(hook.data).then(() => hook).catch(errorsValidation => {
+  return async hook => {
+    try {
+      await validator(schema, { hook })(hook.data);
+      return hook;
+    } catch (errorsValidation) {
       if (Object.keys(errorsValidation).length) {
         throw new errors.BadRequest('Validation failed', errorsValidation);
       }
-    });
+    }
+  };
 }

api/utils/validation.js

@@ -1,29 +1,19 @@
-import isPromise from 'is-promise';
 import * as validation from '../../src/utils/validation';
 
 function createAsyncValidator(rules, params) {
-  return (data = {}) => {
+  return async (data = {}) => {
     const errors = validation.createValidator(rules, params)(data);
 
-    const promises = Object.keys(errors).map(name => {
-      const error = errors[name];
-      const myResolve = () => ({ status: 'resolved', name });
-      const myReject = err => ({ status: 'rejected', name, error: err });
-
-      if (isPromise(error)) {
-        return error.then(myResolve).catch(myReject);
+    const finalErrors = await Object.keys(errors).reduce(async (result, name) => {
+      try {
+        const error = await errors[name];
+        return error ? Object.assign(result, { [name]: error }) : result;
+      } catch (error) {
+        return Object.assign(result, { [name]: error });
       }
+    }, {});
 
-      return error ? myReject() : myResolve();
-    });
-
-    return Promise.all(promises).then(results => {
-      const finalErrors = results
-        .filter(x => x.status === 'rejected')
-        .reduce((prev, next) => ({ ...prev, [next.name]: next.error }), {});
-
-      return Object.keys(finalErrors).length ? Promise.reject(finalErrors) : Promise.resolve(data);
-    });
+    return (await Object.keys(finalErrors).length) ? Promise.reject(finalErrors) : data;
   };
 }
 

src/containers/ChatFeathers/ChatFeathers.js

@@ -49,16 +49,17 @@ export default class ChatFeathers extends Component {
     this.props.app.service('messages').removeListener('created', this.props.addMessage);
   }
 
-  handleSubmit = event => {
+  handleSubmit = async event => {
     event.preventDefault();
-    this.props.app
-      .service('messages')
-      .create({ text: this.state.message })
-      .then(() => this.setState({ message: '', error: false }))
-      .catch(error => {
-        console.log(error);
-        this.setState({ error: error.message || false });
-      });
+
+    try {
+      await this.props.app.service('messages').create({ text: this.state.message });
+
+      this.setState({ message: '', error: false });
+    } catch (error) {
+      console.log(error);
+      this.setState({ error: error.message || false });
+    }
   };
 
   render() {
@@ -69,14 +70,14 @@ export default class ChatFeathers extends Component {
       <div className="container">
         <h1>Chat</h1>
 
-        {user &&
+        {user && (
           <div>
             <ul>
-              {messages.map(msg =>
-                (<li key={`chat.msg.${msg._id}`}>
+              {messages.map(msg => (
+                <li key={`chat.msg.${msg._id}`}>
                   {msg.sentBy.email}: {msg.text}
-                </li>)
-              )}
+                </li>
+              ))}
             </ul>
             <form onSubmit={this.handleSubmit}>
               <input
@@ -91,12 +92,10 @@ export default class ChatFeathers extends Component {
               <button className="btn" onClick={this.handleSubmit}>
                 Send
               </button>
-              {error &&
-                <div className="text-danger">
-                  {error}
-                </div>}
+              {error && <div className="text-danger">{error}</div>}
             </form>
-          </div>}
+          </div>
+        )}
       </div>
     );
   }

src/containers/Login/Login.js

@@ -26,19 +26,26 @@ export default class Login extends Component {
     router: PropTypes.object
   };
 
-  onFacebookLogin = (err, data) => {
+  onFacebookLogin = async (err, data) => {
     if (err) return;
-    this.props.login('facebook', data, false).then(this.successLogin).catch(error => {
+
+    try {
+      const result = await this.props.login('facebook', data, false);
+      this.successLogin(result);
+    } catch (error) {
       if (error.message === 'Incomplete oauth registration') {
         this.context.router.push({
           pathname: '/register',
           state: { oauth: error.data }
         });
       }
-    });
+    }
   };
 
-  login = data => this.props.login('local', data).then(this.successLogin);
+  login = async data => {
+    const result = await this.props.login('local', data);
+    return this.successLogin(result);
+  };
 
   successLogin = data => {
     this.props.notifSend({
@@ -49,18 +56,19 @@ export default class Login extends Component {
     return data;
   };
 
-  FacebookLoginButton = ({ facebookLogin }) =>
-    (<button className="btn btn-primary" onClick={facebookLogin}>
+  FacebookLoginButton = ({ facebookLogin }) => (
+    <button className="btn btn-primary" onClick={facebookLogin}>
       Login with <i className="fa fa-facebook-f" />
-    </button>);
+    </button>
+  );
 
   render() {
     const { user, logout } = this.props;
     return (
       <div className="container">
         <Helmet title="Login" />
         <h1>Login</h1>
-        {!user &&
+        {!user && (
           <div>
             <LoginForm onSubmit={this.login} />
             <p>This will "log you in" as this user, storing the username in the session of the API server.</p>
@@ -71,19 +79,19 @@ export default class Login extends Component {
               onLogin={this.onFacebookLogin}
               component={this.FacebookLoginButton}
             />
-          </div>}
-        {user &&
+          </div>
+        )}
+        {user && (
           <div>
-            <p>
-              You are currently logged in as {user.email}.
-            </p>
+            <p>You are currently logged in as {user.email}.</p>
 
             <div>
               <button className="btn btn-danger" onClick={logout}>
                 <i className="fa fa-sign-out" /> Log Out
               </button>
             </div>
-          </div>}
+          </div>
+        )}
       </div>
     );
   }

src/containers/Register/Register.js

@@ -21,7 +21,10 @@ export default class Register extends Component {
     return location.state && location.state.oauth;
   };
 
-  register = data => this.props.register(data).then(this.successRegister);
+  register = async data => {
+    const result = await this.props.register(data);
+    return this.successRegister(result);
+  };
 
   successRegister = result => {
     this.props.notifSend({