Error: Schema validation failed with the following errors: Data path "" should NOT have additional properties(project)

Question

After migrating application from angular 5 to 6, on running ng serve the following errors pop up.

Schema validation failed with the following errors: Data path "" should NOT have additional properties(project). Error: Schema validation failed with the following errors: Data path "" should NOT have additional properties(project). at MergeMapSubscriber._registry.compile.pipe.operators_1.concatMap.validatorResult [as project] (.../TemplateApp/me-cmf-web-template-angular/node_modules/@angular-devkit/core/src/workspace/workspace.js:210:42) at MergeMapSubscriber._tryNext (/.../me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/operators/mergeMap.js:65:27) at MergeMapSubscriber._next (.../me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/operators/mergeMap.js:55:18) at MergeMapSubscriber.Subscriber.next (/home/training/Attinad_Projects/TemplateApp/me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/Subscriber.js:64:18) at MergeMapSubscriber.notifyNext (.../TemplateApp/me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/operators/mergeMap.js:84:26) at InnerSubscriber._next (.../me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/InnerSubscriber.js:25:21) at InnerSubscriber.Subscriber.next (/.../me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/Subscriber.js:64:18) at MapSubscriber._next (.../me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/operators/map.js:52:26) at MapSubscriber.Subscriber.next (/.../me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/Subscriber.js:64:18) at SwitchMapSubscriber.notifyNext (.../me-cmf-web-template-angular/node_modules/@angular-devkit/core/node_modules/rxjs/internal/operators/switchMap.js:77:26)

I assume that the error is with .angular.json file which I re-named from .angular-cli.json .

My .angular.json file is as follows :

{     "$schema": "./node_modules/@angular/cli/lib/config/schema.json",     "project": {         "name": "mediaweb"     },     "apps": [{             "root": "src",             "outDir": "dist/browser",             "assets": [                 "assets",                 "favicon.ico"             ],             "index": "index.html",             "main": "main.ts",             "polyfills": "polyfills.ts",             "test": "test.ts",             "tsconfig": "tsconfig.app.json",             "testTsconfig": "tsconfig.spec.json",             "prefix": "app",             "styles": [                 "styles.scss",                 "../node_modules/owl.carousel/dist/assets/owl.carousel.css",                 "../node_modules/owl.carousel/dist/assets/owl.theme.default.css",                 "../node_modules/video.js/dist/video-js.css"             ],             "scripts": [                 "../node_modules/jquery/dist/jquery.js",                 "../node_modules/owl.carousel/dist/owl.carousel.js",                 "../node_modules/video.js/dist/ie8/videojs-ie8.js",                 "../node_modules/video.js/dist/video.js"             ],             "environmentSource": "environments/environment.ts",             "environments": {                 "dev": "environments/environment.dev.ts",                 "prod": "environments/environment.prod.ts"             }         },         {             "platform": "server",             "root": "src",             "outDir": "dist/server",             "assets": [                 "assets",                 "favicon.ico"             ],             "index": "index.html",             "main": "main.server.ts",             "test": "test.ts",             "tsconfig": "tsconfig.server.json",             "testTsconfig": "tsconfig.spec.json",             "prefix": "app",             "styles": [                 "styles.scss"             ],             "scripts": [],             "environmentSource": "environments/environment.ts",             "environments": {                 "dev": "environments/environment.dev.ts",                 "prod": "environments/environment.prod.ts"             }         }     ],     "e2e": {         "protractor": {             "config": "./protractor.conf.js"         }     },     "lint": [{             "project": "src/tsconfig.app.json",             "exclude": ["**/node_modules/**", "**/UI/**"]         },         {             "project": "src/tsconfig.spec.json",             "exclude": "**/node_modules/**"         },         {             "project": "e2e/tsconfig.e2e.json",             "exclude": "**/node_modules/**"         }     ],     "test": {         "karma": {             "config": "./karma.conf.js"         }     },     "defaults": {         "styleExt": "scss",         "component": {}     } } 

Should I re-structure the json file, if so how?.

Any help would be great.

Answer 1

The issue is generally because of a version mismatch in your package.json file.

In my Angular 7 app, I have changed "@angular-devkit/build-angular": "^0.800.2" to "@angular-devkit/build-angular": "~0.7.0".

Then I ran the command npm install after deleting node_modules.

Aside: Use ^ carefully. Your working code may not work in the future if there is a major change in the package used.