Add Controller.validate and automatically handle validation errors

src/Controller.ts

@@ -2,7 +2,7 @@ import {RequestHandler, Router} from "express";
 import {PathParams} from "express-serve-static-core";
 import config from "config";
 import Logger from "./Logger";
-import Validator from "./db/Validator";
+import Validator, {ValidationBag} from "./db/Validator";
 
 export default abstract class Controller {
     private static readonly routes: { [p: string]: string } = {};
@@ -82,9 +82,24 @@ export default abstract class Controller {
 
     private wrap(handler: RequestHandler): RequestHandler {
         return (req, res, next) => {
+            function handleErr(e: any) {
+                if (e instanceof ValidationBag) {
+                    req.flash('validation', e.getMessages());
+                    res.redirectBack();
+                } else {
+                    next(e);
+                }
+            }
+
+            try {
                 const promise = handler.call(this, req, res, next);
                 if (promise instanceof Promise) {
-                promise.catch(err => next(err));
+                    promise.catch(e => {
+                        handleErr(e);
+                    });
+                }
+            } catch (e) {
+                handleErr(e);
             }
         };
     }
@@ -118,12 +133,22 @@ export default abstract class Controller {
     }
 
     protected async validate(validationMap: { [p: string]: Validator<any> }, body: any): Promise<void> {
+        const bag = new ValidationBag();
+
         for (const p in validationMap) {
             if (validationMap.hasOwnProperty(p)) {
+                try {
                     await validationMap[p].execute(p, body[p], false);
+                } catch (e) {
+                    if (e instanceof ValidationBag) {
+                        bag.addBag(e);
+                    } else throw e;
                 }
             }
         }
+
+        if (bag.hasMessages()) throw bag;
+    }
 }
 
 export type RouteParams = { [p: string]: string } | string[] | string | number;