# Configure and use Yarn with CodeArtifact
<a name="npm-yarn"></a>

After you create a repository, you can use the Yarn client to manage npm packages.

**Note**  
`Yarn 1.X` reads and uses information from your npm configuration file (.npmrc), while `Yarn 2.X` does not. The configuration for `Yarn 2.X` must be defined in the .yarnrc.yml file.

**Contents**
+ [Configure Yarn 1.X with the `aws codeartifact login` command](#npm-yarn-configure-login)
+ [Configure Yarn 2.X with the `yarn config set` command](#npm-yarn-configure-yarn-command)

## Configure Yarn 1.X with the `aws codeartifact login` command
<a name="npm-yarn-configure-login"></a>

For `Yarn 1.X`, you can configure Yarn with CodeArtifact using the `aws codeartifact login` command. The `login` command will configure your \~/.npmrc file with your CodeArtifact repository endpoint information and credentials. With `Yarn 1.X`, `yarn` commands use the configuration information from the \~/.npmrc file.

**To configure `Yarn 1.X` with the login command**

1. If you haven't done so already, configure your AWS credentials for use with the AWS CLI, as described in [Getting started with CodeArtifact](getting-started.md).

1. To run the `aws codeartifact login` command successfully, npm must be installed. See [Downloading and installing Node.js and npm](https://docs.npmjs.com/downloading-and-installing-node-js-and-npm/) in the *npm documentation* for installation instructions.

1. Use the `aws codeartifact login` command to fetch CodeArtifact credentials and configure your \~/.npmrc file.
   + Replace {{my\_domain}} with your CodeArtifact domain name.
   + Replace {{111122223333}} with the AWS account ID of the owner of the domain. If you are accessing a repository in a domain that you own, you don't need to include `--domain-owner`. For more information, see [Cross-account domains](domain-overview.md#domain-overview-cross-account).
   + Replace {{my\_repo}} with your CodeArtifact repository name.

   ```
   aws codeartifact login --tool npm --domain {{my_domain}} --domain-owner {{111122223333}} --repository {{my_repo}}
   ```

   The `login` command makes the following changes to your \~/.npmrc file:
   + Adds an authorization token after fetching it from CodeArtifact using your AWS credentials.
   + Sets the npm registry to the repository specified by the `--repository` option.
   + **For npm 6 and lower:** Adds `"always-auth=true"` so the authorization token is sent for every npm command.

   The default authorization period after calling `login` is 12 hours, and `login` must be called to refresh the token periodically. For more information about the authorization token created with the `login` command, see [Tokens created with the `login` command](tokens-authentication.md#auth-token-login).

1. **For npm 7.X and 8.X**, you must add `always-auth=true` to your \~/.npmrc file to use Yarn.

   1. Open your \~/.npmrc file in a text editor and add `always-auth=true` on a new line.

You can use the `yarn config list` command to check that Yarn is using the correct configuration. After running the command, check the values in the `info npm config` section. The contents should look similar to the following snippet.

```
info npm config
{
  registry: 'https://my_domain-111122223333.d.codeartifact.us-west-2.amazonaws.com/npm/my_repo/',
  '//my_domain-111122223333.d.codeartifact.us-west-2.amazonaws.com/npm/my_repo/:_authToken': 'eyJ2ZXI...',
  'always-auth': true
}
```

## Configure Yarn 2.X with the `yarn config set` command
<a name="npm-yarn-configure-yarn-command"></a>

The following procedure details how to configure `Yarn 2.X` by updating your `.yarnrc.yml` configuration from the command line with the `yarn config set` command.

**To update the `yarnrc.yml` configuration from the command line**

1. If you haven't done so already, configure your AWS credentials for use with the AWS CLI, as described in [Getting started with CodeArtifact](getting-started.md).

1. Use the `aws codeartifact get-repository-endpoint` command to get your CodeArtifact repository's endpoint.
   + Replace {{my\_domain}} with your CodeArtifact domain name.
   + Replace {{111122223333}} with the AWS account ID of the owner of the domain. If you are accessing a repository in a domain that you own, you don't need to include `--domain-owner`. For more information, see [Cross-account domains](domain-overview.md#domain-overview-cross-account).
   + Replace {{my\_repo}} with your CodeArtifact repository name.

   ```
   aws codeartifact get-repository-endpoint --domain {{my_domain}} --domain-owner {{111122223333}} --repository {{my_repo}} --format npm
   ```

1. Update the `npmRegistryServer` value in your .yarnrc.yml file with your repository endpoint.

   ```
   yarn config set npmRegistryServer "https://{{my_domain}}-{{111122223333}}.d.codeartifact.{{region}}.amazonaws.com/npm/{{my_repo}}/"
   ```

1. Fetch a CodeArtifact authorization token and store it in an environment variable.
**Note**  
The following command is for macOS or Linux machines. For information on configuring environment variables on a Windows machine, see [Pass an auth token using an environment variable](tokens-authentication.md#env-var).
   + Replace {{my\_domain}} with your CodeArtifact domain name.
   + Replace {{111122223333}} with the AWS account ID of the owner of the domain. If you are accessing a repository in a domain that you own, you don't need to include `--domain-owner`. For more information, see [Cross-account domains](domain-overview.md#domain-overview-cross-account).
   + Replace {{my\_repo}} with your CodeArtifact repository name.

   ```
   export CODEARTIFACT_AUTH_TOKEN=`aws codeartifact get-authorization-token --domain {{my_domain}} --domain-owner {{111122223333}} --query authorizationToken --output text`
   ```

1. Use the `yarn config set` command to add your CodeArtifact authentication token to your .yarnrc.yml file. Replace the URL in the following command with your repository endpoint URL from Step 2.

   ```
   yarn config set 'npmRegistries["https://{{my_domain}}-{{111122223333}}.d.codeartifact.{{region}}.amazonaws.com/npm/{{my_repo}}/"].npmAuthToken' "${CODEARTIFACT_AUTH_TOKEN}"
   ```

1. Use the `yarn config set` command to set the value of `npmAlwaysAuth` to `true`. Replace the URL in the following command with your repository endpoint URL from Step 2.

   ```
   yarn config set 'npmRegistries["https://{{my_domain}}-{{111122223333}}.d.codeartifact.{{region}}.amazonaws.com/npm/{{my_repo}}/"].npmAlwaysAuth' "true"
   ```

After configuring, your .yarnrc.yml configuration file should have contents similar to the following snippet.

```
npmRegistries:
  "https://my_domain-111122223333.d.codeartifact.us-west-2.amazonaws.com/npm/my_repo/":
    npmAlwaysAuth: true
    npmAuthToken: eyJ2ZXI...

npmRegistryServer: "https://my_domain-111122223333.d.codeartifact.us-west-2.amazonaws.com/npm/my_repo/"
```

You can also use the `yarn config` command to check the values of `npmRegistries` and `npmRegistryServer`.