[解決済み] モジュール "@angular-devkit/build-angular" が見つかりませんでした。

質問

Angular 6.0.1にアップデートした後、以下のエラーが発生します。 ng serve :

Could not find module "@angular-devkit/build-angular" from "/home/Projects/myProjectName".
Error: Could not find module "@angular-devkit/build-angular" from "/home/Projects/myProjectName".
    at Object.resolve (/home/Projects/myProjectName/node_modules/@angular-devkit/core/node/resolve.js:141:11)
    at Observable.rxjs_1.Observable [as _subscribe] (/home/Projects/myProjectName/node_modules/@angular-devkit/architect/src/architect.js:132:40)

ng update は、すべてが整ったことを意味します。削除する node_modules フォルダを作成し、新たに npm install をインストールしてもダメでした。

私のプロジェクトは ng2-admin(Angular4版) . 以下は、私のpackage.jsonのdependeciesです。

 "dependencies": {
    "@angular/animations": "^6.0.1",
    "@angular/common": "^6.0.1",
    "@angular/compiler": "^6.0.1",
    "@angular/core": "^6.0.1",
    "@angular/forms": "^6.0.1",
    "@angular/http": "^6.0.1",
    "@angular/platform-browser": "^6.0.1",
    "@angular/platform-browser-dynamic": "^6.0.1",
    "@angular/platform-server": "^6.0.1",
    "@angular/router": "^6.0.1",
    "@ng-bootstrap/ng-bootstrap": "1.0.0-alpha.26",
    "@ngx-translate/core": "^10.0.1",
    "@ngx-translate/http-loader": "^3.0.1",
    "amcharts3": "github:amcharts/amcharts3",
    "ammap3": "github:amcharts/ammap3",
    "angular-table": "^1.0.4",
    "angular2-csv": "^0.2.5",
    "angular2-datatable": "0.6.0",
    "animate.css": "3.5.2",
    "bootstrap": "4.0.0-alpha.6",
    "bower": "^1.8.4",
    "chart.js": "1.1.1",
    "chartist": "0.10.1",
    "chroma-js": "1.3.3",
    "ckeditor": "4.6.2",
    "core-js": "2.4.1",
    "easy-pie-chart": "2.1.7",
    "font-awesome": "4.7.0",
    "fullcalendar": "3.3.1",
    "google-maps": "3.2.1",
    "ionicons": "2.0.1",
    "jquery": "3.2.1",
    "jquery-slimscroll": "1.3.8",
    "leaflet": "0.7.7",
    "leaflet-map": "0.2.1",
    "lodash": "4.17.4",
    "ng2-ckeditor": "1.1.6",
    "ng2-completer": "^1.6.3",
    "ng2-handsontable": "^2.1.0-rc.3",
    "ng2-slim-loading-bar": "^4.0.0",
    "ng2-smart-table": "^1.0.3",
    "ng2-tree": "2.0.0-alpha.5",
    "ngx-uploader": "4.2.4",
    "normalize.css": "6.0.0",
    "roboto-fontface": "0.7.0",
    "rxjs": "^6.1.0",
    "rxjs-compat": "^6.1.0",
    "zone.js": "0.8.26"
  },
  "devDependencies": {
    "@angular/cli": "^6.0.1",
    "@angular/compiler-cli": "^6.0.1",
    "@types/fullcalendar": "2.7.40",
    "@types/jasmine": "2.5.38",
    "@types/jquery": "2.0.41",
    "@types/jquery.slimscroll": "1.3.30",
    "@types/lodash": "4.14.61",
    "@types/node": "6.0.69",
    "codelyzer": "3.0.1",
    "gh-pages": "0.12.0",
    "jasmine-core": "2.5.2",
    "jasmine-spec-reporter": "3.2.0",
    "karma": "1.4.1",
    "karma-chrome-launcher": "2.0.0",
    "karma-cli": "1.0.1",
    "karma-coverage-istanbul-reporter": "0.2.0",
    "karma-jasmine": "1.1.0",
    "karma-jasmine-html-reporter": "0.2.2",
    "npm-run-all": "4.0.2",
    "protractor": "5.1.0",
    "rimraf": "2.6.1",
    "standard-changelog": "1.0.1",
    "stylelint": "7.10.1",
    "ts-node": "2.1.2",
    "tslint": "5.2.0",
    "tslint-eslint-rules": "4.0.0",
    "tslint-language-service": "0.9.6",
    "typescript": "^2.7.2",
    "typogr": "0.6.6",
    "underscore": "1.8.3",
    "wintersmith": "2.2.5",
    "wintersmith-sassy": "1.1.0"
  }

と私のangular.jsonです。

{
  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "newProjectRoot": "projects",
  "projects": {
    "ng2-admin": {
      "root": "",
      "sourceRoot": "src",
      "projectType": "application",
      "architect": {
        "build": {
          "builder": "@angular-devkit/build-angular:browser",
          "options": {
            "outputPath": "dist",
            "index": "src/index.html",
            "main": "src/main.ts",
            "tsConfig": "src/tsconfig.app.json",
            "polyfills": "src/polyfills.ts",
            "assets": [
              "src/assets",
              "src/favicon.ico"
            ],
            "styles": [
              "node_modules/roboto-fontface/css/roboto/sass/roboto-fontface.scss",
              "node_modules/normalize.css/normalize.css",
              "node_modules/font-awesome/scss/font-awesome.scss",
              "node_modules/ionicons/scss/ionicons.scss",
              "node_modules/bootstrap/scss/bootstrap.scss",
              "node_modules/leaflet/dist/leaflet.css",
              "node_modules/chartist/dist/chartist.css",
              "node_modules/fullcalendar/dist/fullcalendar.css",
              "node_modules/handsontable/dist/handsontable.full.css",
              "node_modules/ng2-slim-loading-bar/style.css",
              "src/app/theme/theme.scss",
              "src/styles.scss"
            ],
            "scripts": [
              "node_modules/jquery/dist/jquery.js",
              "node_modules/easy-pie-chart/dist/jquery.easypiechart.js",
              "node_modules/jquery-slimscroll/jquery.slimscroll.js",
              "node_modules/tether/dist/js/tether.js",
              "node_modules/bootstrap/dist/js/bootstrap.js",
              "node_modules/handsontable/dist/handsontable.full.js",
              "node_modules/chroma-js/chroma.js"
            ]
          },
          "configurations": {
            "production": {
              "optimization": true,
              "outputHashing": "all",
              "sourceMap": false,
              "extractCss": true,
              "namedChunks": false,
              "aot": true,
              "extractLicenses": true,
              "vendorChunk": false,
              "buildOptimizer": true,
              "fileReplacements": [
                {
                  "replace": "src/environments/environment.ts",
                  "with": "src/environments/environment.prod.ts"
                }
              ]
            }
          }
        },
        "serve": {
          "builder": "@angular-devkit/build-angular:dev-server",
          "options": {
            "browserTarget": "ng2-admin:build"
          },
          "configurations": {
            "production": {
              "browserTarget": "ng2-admin:build:production"
            }
          }
        },
        "extract-i18n": {
          "builder": "@angular-devkit/build-angular:extract-i18n",
          "options": {
            "browserTarget": "ng2-admin:build"
          }
        },
        "test": {
          "builder": "@angular-devkit/build-angular:karma",
          "options": {
            "main": "src/test.ts",
            "karmaConfig": "./karma.conf.js",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "src/tsconfig.spec.json",
            "scripts": [
              "node_modules/jquery/dist/jquery.js",
              "node_modules/easy-pie-chart/dist/jquery.easypiechart.js",
              "node_modules/jquery-slimscroll/jquery.slimscroll.js",
              "node_modules/tether/dist/js/tether.js",
              "node_modules/bootstrap/dist/js/bootstrap.js",
              "node_modules/handsontable/dist/handsontable.full.js",
              "node_modules/chroma-js/chroma.js"
            ],
            "styles": [
              "node_modules/roboto-fontface/css/roboto/sass/roboto-fontface.scss",
              "node_modules/normalize.css/normalize.css",
              "node_modules/font-awesome/scss/font-awesome.scss",
              "node_modules/ionicons/scss/ionicons.scss",
              "node_modules/bootstrap/scss/bootstrap.scss",
              "node_modules/leaflet/dist/leaflet.css",
              "node_modules/chartist/dist/chartist.css",
              "node_modules/fullcalendar/dist/fullcalendar.css",
              "node_modules/handsontable/dist/handsontable.full.css",
              "node_modules/ng2-slim-loading-bar/style.css",
              "src/app/theme/theme.scss",
              "src/styles.scss"
            ],
            "assets": [
              "src/assets",
              "src/favicon.ico"
            ]
          }
        },
        "lint": {
          "builder": "@angular-devkit/build-angular:tslint",
          "options": {
            "tsConfig": [
              "src/tsconfig.app.json",
              "src/tsconfig.spec.json"
            ],
            "exclude": []
          }
        }
      }
    },
    "ng2-admin-e2e": {
      "root": "",
      "sourceRoot": "",
      "projectType": "application",
      "architect": {
        "e2e": {
          "builder": "@angular-devkit/build-angular:protractor",
          "options": {
            "protractorConfig": "./protractor.conf.js",
            "devServerTarget": "ng2-admin:serve"
          }
        },
        "lint": {
          "builder": "@angular-devkit/build-angular:tslint",
          "options": {
            "tsConfig": [
              "e2e/tsconfig.e2e.json"
            ],
            "exclude": []
          }
        }
      }
    }
  },
  "defaultProject": "ng2-admin",
  "schematics": {
    "@schematics/angular:component": {
      "prefix": "app",
      "styleext": "scss"
    },
    "@schematics/angular:directive": {
      "prefix": "app"
    }
  }
}

解決方法は？

インストール @angular-devkit/build-angular をdev依存とする。このパッケージは Angular 6.0 で新たに導入されました。

npm install --save-dev @angular-devkit/build-angular

または

yarn add @angular-devkit/build-angular --dev