migration-angular.md

Transitioning to Nx

Within an Nx workspace, you gain many capabilities that help you build applications and libraries using a monorepo approach. If you are currently using an Angular CLI workspace, you can transform it into an Nx workspace.

Prerequisites

• The major version of your Angular CLI must align with the version of Nx you are upgrading to. For example, if you're using Angular CLI version 7, you must transition using the latest version 7 release of Nx.
• Currently, transforming an Angular CLI workspace to an Nx workspace automatically only supports a single project. If you have more than one project in your Angular CLI workspace, you can still migrate manually.

Using the Nx CLI while preserving the existing structure

To use the Nx CLI in an existing Angular CLI workspace while keeping your existing file structure in place, use the ng add command with the --preserveAngularCLILayout option:

ng add @nrwl/workspace --preserveAngularCLILayout

This installs the @nrwl/workspace package into your workspace and applies the following changes to your workspace:

• Adds and installs the @nrwl/workspace package in your development dependencies.
• Creates an nx.json file in the root of your workspace.
• Adds a decorate-angular-cli.js to the root of your workspace, and a postinstall script in your package.json to run the script when your dependencies are updated. The script forwards the ng commands to the Nx CLI (nx) to enable features such as Computation Caching.

After the process completes, you can continue using the same serve/build/lint/test commands you are used to.

Transforming an Angular CLI workspace to an Nx workspace

To transform an Angular CLI workspace to an Nx workspace, run the following command:

ng add @nrwl/workspace

This installs the @nrwl/workspace package into your workspace and runs a generator (or schematic) to transform your workspace. The generator applies the following changes to your workspace:

• Installs the packages for the Nx plugin @nrwl/angular in your package.json.
• Creates an nx.json file in the root of your workspace.
• Creates configuration files for Prettier.
• Creates an apps folder for generating applications.
• Creates a libs folder for generating libraries.
• Creates a tools folder that includes files for custom workspace tooling, such as workspace-specific generators and scripts.
• Moves your application into the apps folder, and updates the relevant file paths in your configuration files.
• Moves your e2e suite into the apps/{{app name}}-e2e folder, and updates the relevant file paths in your configuration files.
• Updates your package.json with scripts to run various Nx workspace commands.
• Updates your angular.json configuration to reflect the new paths.

After the changes are applied, your workspace file structure should look similar to the one below:

<workspace name>/
├── apps/
│   ├── <app name>/
│   │   ├── src/
│   │   │   ├── app/
│   │   │   ├── assets/
│   │   │   ├── environments/
│   │   │   ├── favicon.ico
│   │   │   ├── index.html
│   │   │   ├── main.ts
│   │   │   ├── polyfills.ts
│   │   │   ├── styles.css
│   │   │   └── test.ts
│   │   ├── .browserslistrc
│   │   ├── karma.conf.js
│   │   ├── tsconfig.app.json
│   │   └── tsconfig.spec.json
│   └── <app name>-e2e/
│       ├── src/
│       ├── protractor.conf.js | cypress.json
│       └── tsconfig.json
├── libs/
├── tools/
├── .editorconfig
├── .gitignore
├── .prettierignore
├── .prettierrc
├── angular.json
├── decorate-angular-cli.js
├── karma.conf.js
├── nx.json
├── package.json
├── README.md
└── tsconfig.base.json

Your workspace is now powered by Nx! You can verify out that your application still runs as intended:

• To serve, run ng serve.
• To build, run ng build.
• To run unit tests, run ng test.
• To run e2e tests, run ng e2e.
• To see your project graph, run nx graph.

Your project graph will grow as you add, and use more applications and libraries. You can add the --watch flag to nx graph to see this changes in-browser as you add them.

Learn more about the advantages of Nx in the following guides:

• Using Cypress for e2e tests
• Using Jest for unit tests
• Computation Caching
• Rebuilding and Retesting What is Affected

Transitioning Manually

If you are unable to automatically transform your Angular CLI workspace to an Nx workspace using the ng add method, there are some manual steps you can take to move your project(s) into an Nx workspace.

Generating a new workspace

To start, run the command to generate an Nx workspace with an Angular application.

Using npx

npx create-nx-workspace myorg --preset=angular

Using npm init

npm init nx-workspace myorg --preset=angular

Using yarn create

yarn create nx-workspace myorg --preset=angular

When prompted for the application name, enter the project name from your current angular.json file.

A new Nx workspace with your org name as the folder name, and your application name as the first application is generated.

<workspace name>/
├── apps/
│   ├── <app name>/
│   │   ├── src/
│   │   │   ├── app/
│   │   │   ├── assets/
│   │   │   ├── environments/
│   │   │   ├── favicon.ico
│   │   │   ├── index.html
│   │   │   ├── main.ts
│   │   │   ├── polyfills.ts
│   │   │   ├── styles.css
│   │   │   └── test.ts
│   │   ├── browserslist
│   │   ├── jest.conf.js
│   │   ├── tsconfig.app.json
│   │   ├── tsconfig.json
│   │   ├── tslint.json
│   │   └── tsconfig.spec.json
│   └── <app name>-e2e/
│       ├── src/
│       ├── cypress.json
│       ├── tsconfig.e2e.json
│       ├── tslint.json
│       └── tsconfig.json
├── libs/
├── tools/
├── .prettierignore
├── .prettierrc
├── README.md
├── angular.json
├── jest.config.js
├── nx.json
├── package.json
├── tsconfig.base.json
└── tslint.json

Copying over application files

Your application code is self-contained within the src folder of your Angular CLI workspace.

• Copy the src folder from your Angular CLI project to the apps/<app name> folder, overwriting the existing src folder.
• Copy any project-specific files, such as browserslist, or service worker configuration files into their relative path under the apps/<app name> folder.
• Transfer the assets, scripts, styles, and build-specific configuration, such as service worker configuration, from your Angular CLI angular.json to the Nx workspace angular.json file.

Verify your app runs correctly by running:

ng serve <app name>

Updating your unit testing configuration

Nx uses Jest by default. If you have any custom Jest configuration, you need to update the workspace Jest configuration also.

Verify your tests run correctly by running:

ng test <app name>

If you are using Karma for unit testing:

• Copy the karma.conf.js file to your apps/<app name> folder.
• Copy the test.ts file to your apps/<app name>/src folder.
• Copy the test target in your architect configuration from your Angular CLI angular.json file into your Nx workspace angular.json file.
• Update your test target to prepend apps/<app name> to each of the file paths.

{
  "projects": {
    "<app name>": {
      "projectType": "application",
      "schematics": {},
      "root": "apps/<app name>",
      "sourceRoot": "apps/<app name>/src",
      "prefix": "myapp",
      "architect": {
        "test": {
          "builder": "@angular-devkit/build-angular:karma",
          "options": {
            "main": "apps/<app name>/src/test.ts",
            "polyfills": "apps/<app name>/src/polyfills.ts",
            "tsConfig": "apps/<app name>/tsconfig.spec.json",
            "karmaConfig": "apps/<app name>/karma.conf.js",
            "assets": [
              "apps/<app name>/src/favicon.ico",
              "apps/<app name>/src/assets"
            ],
            "styles": ["apps/<app name>/src/styles.css"],
            "scripts": []
          }
        }
      }
    }
  },
  "cli": {
    "defaultCollection": "@nrwl/angular"
  },
  "schematics": {
    "@nrwl/angular:application": {
      "unitTestRunner": "jest",
      "e2eTestRunner": "cypress"
    },
    "@nrwl/angular:library": {
      "unitTestRunner": "jest"
    }
  },
  "defaultProject": "<app name>"
}

Jest will be used by default when generating new applications. If you want to continue using Karma, set the unitTestRunner to karma in the schematics section of the angular.json file.

• Update test-setup.ts to test.ts in the files array of the apps/<app name>/tsconfig.spec.json file.

{
  "extends": "./tsconfig.json",
  "compilerOptions": {
    "outDir": "../../dist/out-tsc",
    "module": "commonjs",
    "types": ["node"]
  },
  "files": ["src/test.ts", "src/polyfills.ts"],
  "include": ["**/*.spec.ts", "**/*.d.ts"]
}

Verify your tests run correctly by running:

ng test <app name>

Updating your E2E testing configuration

Nx uses Cypress by default. If you are already using Cypress, copy your E2E setup files into the apps/<app name>-e2e folder and verify your tests still run correctly by running:

ng e2e <app name>-e2e

If you are using Protractor for E2E testing:

• Delete the apps/<app name>-e2e folder that was generated to use Cypress.
• Copy the e2e folder from your Angular CLI workspace into the apps file to your apps/<app name> folder.
• Rename the e2e folder to <app name>-e2e.
• In the Nx workspace angular.json, update your <app name>-e2e project with the Protractor configuration.

{
  "version": 1,
  "projects": {
    "<app name>-e2e": {
      "root": "apps/<app name>-e2e",
      "projectType": "application",
      "architect": {
        "e2e": {
          "builder": "@angular-devkit/build-angular:protractor",
          "options": {
            "protractorConfig": "apps/<app name>-e2e/protractor.conf.js",
            "devServerTarget": "<app name>:serve"
          },
          "configurations": {
            "production": {
              "devServerTarget": "<app name>:serve:production"
            }
          }
        },
        "lint": {
          "builder": "@angular-devkit/build-angular:tslint",
          "options": {
            "tsConfig": "apps/<app name>-e2e/tsconfig.e2e.json",
            "exclude": ["**/node_modules/**", "!apps/<app name>-e2e/**/*"]
          }
        }
      }
    }
  },
  "cli": {
    "defaultCollection": "@nrwl/angular"
  },
  "schematics": {
    "@nrwl/angular:application": {
      "unitTestRunner": "jest",
      "e2eTestRunner": "cypress"
    },
    "@nrwl/angular:library": {
      "unitTestRunner": "jest"
    }
  },
  "defaultProject": "<app name>"
}

Create a tsconfig.e2e.json file under apps/<app name>-e2e folder:

{
  "extends": "./tsconfig.json",
  "compilerOptions": {
    "outDir": "../../dist/out-tsc"
  }
}

Update the apps/<app name>/tsconfig.json to extend the root tsconfig.json:

{
  "extends": "../../tsconfig.json",
  "compilerOptions": {
    "outDir": "../../out-tsc/<app name>-e2e",
    "module": "commonjs",
    "target": "es5",
    "types": ["jasmine", "jasminewd2", "node"]
  }
}

Verify your E2E tests run correctly by running:

ng e2e <app name>-e2e

Cypress will be used by default when generating new applications. If you want to continue using Protractor, set the e2eTestRunner to protractor in the schematics section of the angular.json file.

Updating your linting configuration

For lint rules, migrate your existing rules into the root tslint.json file.

Verify your lint checks run correctly by running:

npm run lint

OR

yarn lint

Learn more about the advantages of Nx in the following guides:

Using Cypress for e2e tests
Using Jest for unit tests
Rebuilding and Retesting What is Affected