Tagging an Amazon ECR Public repository

To help you manage your Amazon ECR Public repositories, you can optionally assign your own metadata to each repository by using tags. This topic provides an overview about tags and how to create them.

Tag basics

A tag is a label that you assign to an AWS resource. Each tag consists of a key and an optional value. You define both of them.

You can use tags to categorize your AWS resources in different ways, for example, by purpose, owner, or environment. This is useful when you have many resources of the same type. This is because you can quickly identify a specific resource based on the tags you've assigned to it. For example, you can define a set of tags for your account's Amazon ECR Public repositories to track each repository's owner.

We recommend that you devise a set of tag keys that meets your specific needs. Using a consistent set of tag keys can help you keep better track of your resources and find specific resources quickly. That is, you can search and filter the resources based on the specific tags that you add.

Tags don't have any semantic meaning to Amazon ECR and are interpreted strictly as a string of characters. Tags aren't automatically assigned to your resources. You can edit tag keys and values, and you can remove tags from a resource at any time. You can set the value of a tag to an empty string. However, you can't set the value of a tag to null. If you add a tag that has the same key as an existing tag on that resource, the new value overwrites the old value. If you delete a resource, any tags for the resource are also deleted.

You can work with tags using the AWS Management Console, the AWS CLI, and the Amazon ECR Public API.

If you're using AWS Identity and Access Management (IAM), you can control which users in your AWS account have permission to manage tags.

Tagging your resources

You can tag new or existing Amazon ECR Public repositories.

If you're using the Amazon ECR console, you can apply tags to new resources when they're created or to existing resources by using the Tags option on the navigation pane at any time.

If you're using the Amazon ECR Public API, the AWS CLI, or an AWS SDK, you can apply tags to new repositories using the tags parameter on the CreateRepository API action or use the TagResource API action to apply tags to existing resources. For more information, see TagResource.

Additionally, if tags can't be applied when a repository is created, the repository creation process is rolled back. This ensures that repositories are either created with tags or not created at all and that no repositories are left untagged at any time. By tagging repositories when they're created, you eliminate the need to run custom tagging scripts after the repository is created.

Tag restrictions

The following restrictions and conditions apply to tags:

• A maximum of 50 tags can be associated with a repository.

• For each repository, each tag key must be unique, and each tag key can have only one value.

• A key can be up to 128 Unicode characters long, and must be in UTF-8.

• A value can be up to 256 Unicode characters long, and must be in UTF-8.

• If your tagging schema is used across multiple services and resources, remember that other services might have restrictions on allowed characters. Characters that are allowed across most services are letters, numbers, white spaces (representable in UTF-8), plus signs (+), hyphens (-), equal signs (=), periods (.) underscores (_), colons (:) slashes (/), and the at symbol (@).

• Tag keys and values are case sensitive.

• Don't use the aws: prefix for either keys or values. It's reserved for AWS use only. You can't edit or delete tag keys or values with this prefix. Tags with this prefix aren't included in your tag per resource quota.

Working with tags using the console

Using the Amazon ECR console, you can manage the tags that are associated with new or existing repositories.

When you select a specific repository in the Amazon ECR console, you can view the tags by selecting Tags in the navigation pane.

To add a tag to a public repository

1. Open the Amazon ECR console at https://console.aws.amazon.com/ecr/.

2. From the navigation bar, select the AWS Region to use.

3. In the navigation pane, choose Repositories.

4. On the Repositories page, on the Public tab, choose the repository to view.

5. On the Repositories > repository_name page, select Tags from the navigation pane.

6. On the Tags page, select Add tags, Add tag.

7. On the Edit Tags page, specify the key and value for each tag, and then choose Save.

To delete a tag from an individual resource

1. Open the Amazon ECR console at https://console.aws.amazon.com/ecr/.

2. From the navigation bar, select the Region to use.

3. On the Repositories page, on the Public tab, choose the repository to view.

4. On the Repositories > repository_name page, select Tags from the navigation pane.

5. On the Tags page, select Edit.

6. On the Edit tags page, select Remove for each tag you want to delete, and choose Save.

Working with tags using the AWS CLI or API

Use the following to add, update, list, and delete the tags for your resources. The corresponding documentation provides examples.

Tagging support for Amazon ECR Public resources
Task	AWS CLI	API action
Add or overwrite one or more tags.	tag-resource	TagResource
Delete one or more tags.	untag-resource	UntagResource

The following examples show how to manage tags using the AWS CLI.

Example 1: Tag an existing public repository

The following command tags an existing public repository.

aws ecr-public tag-resource \
      --resource-arn arn:aws:ecr-public::account_id:repository/repository_name \
      --tags Key=stack,Value=dev \
      --region us-east-1

Example 2: Tag an existing public repository with multiple tags

The following command tags an existing repository.

aws ecr-public tag-resource \
      --resource-arn arn:aws:ecr-public::account_id:repository/repository_name \
      --tags Key=key1,Value=value1 Key=key2,Value=value2 Key=key3,Value=value3 \
      --region us-east-1

Example 3: Untag an existing public repository

The following command deletes a tag from an existing public repository.

aws ecr-public untag-resource \
      --resource-arn arn:aws:ecr-public::account_id:repository/repository_name \
      --tag-keys tag_key \
      --region us-east-1

Example 4: List tags for a public repository

The following command lists the tags that are associated with an existing public repository.

aws ecr-public list-tags-for-resource \
      --resource-arn arn:aws:ecr-public::account_id:repository/repository_name \
      --region us-east-1

Example 5: Create a public repository and apply a tag

The following command creates a public repository that's named test-repo and adds a tag with key team and value devs.

aws ecr-public create-repository \
      --repository-name test-repo \
      --tags Key=team,Value=devs \
      --region us-east-1