Adding Tags in AWS CDK - BioErrorLog Tech Blog

This is a quick reference guide for adding tags in AWS CDK.

Introduction
Environment
Adding Tags in CDK
- Examples
  - Adding Tags at the Stack Level
  - Adding Tags at the Construct Level
- Note: Deprecated Tag Assignment Method
Conclusion
References

Introduction

When adding tags to resources in CDK, I often forget the exact method and end up searching for it again.

To avoid having to look it up every time, I'm documenting the tag assignment methods here.

Note: This article was translated from my original post.

Environment

The work was done in the following environment:

CDK version: 1.92.0
OS: Amazon Linux 2 (Cloud9)

Adding Tags in CDK

To add tags in CDK, the recommended approach is to use the Tags class.

Tags and the AWS CDK - AWS Cloud Development Kit (AWS CDK) v2

※There's also a method using the Tag class, but it's deprecated.

Let's look at how to add tags using Python as an example.

Examples

Tags are added in the following format:

Tags.of(SCOPE).add(key, value)

For SCOPE, specify a Construct or Stack, and for key and value, specify the tag key and value respectively.

Here are some concrete examples.

Adding Tags at the Stack Level

from aws_cdk import (
    aws_s3 as s3,
    core
)


class TagSampleStack(core.Stack):

    def __init__(self, scope: core.Construct, construct_id: str, **kwargs) -> None:
        super().__init__(scope, construct_id, **kwargs)
        
        s3_01 = s3.Bucket(self, "TagTestBucket01", bucket_name="tag-test-bucket-001")
        s3_02 = s3.Bucket(self, "TagTestBucket02", bucket_name="tag-test-bucket-002")


app = core.App()
tag_sample_stack = TagSampleStack(app, "tag-sample")

# Add tags to the Stack
core.Tags.of(tag_sample_stack).add("Project", "TagTest")

app.synth()

When you add a tag to a Stack this way, the tag is applied to all resources contained in that Stack.

In the above case, both S3 buckets tag-test-bucket-001 and tag-test-bucket-002 included in the Stack will be tagged with Project: TagTest.

Adding Tags at the Construct Level

from aws_cdk import (
    aws_s3 as s3,
    core
)


class TagSampleStack(core.Stack):

    def __init__(self, scope: core.Construct, construct_id: str, **kwargs) -> None:
        super().__init__(scope, construct_id, **kwargs)
        
        s3_01 = s3.Bucket(self, "TagTestBucket01", bucket_name="tag-test-bucket-001")
        s3_02 = s3.Bucket(self, "TagTestBucket02", bucket_name="tag-test-bucket-002")

        # Add tags to the Construct
        core.Tags.of(s3_01).add("Project", "TagTest")


app = core.App()
tag_sample_stack = TagSampleStack(app, "tag-sample")

app.synth()

When you add a tag to a specific Construct this way, the tag is applied only to that target Construct.

In the above case, only the S3 bucket tag-test-bucket-001 will be tagged with Project: TagTest.

Note: Deprecated Tag Assignment Method

While you can add tags using the Tag class as shown below, this method is deprecated.

Tag.add(SCOPE, key, value)

Code example:

from aws_cdk import (
    aws_s3 as s3,
    core
)


class TagSampleStack(core.Stack):

    def __init__(self, scope: core.Construct, construct_id: str, **kwargs) -> None:
        super().__init__(scope, construct_id, **kwargs)
        
        s3_01 = s3.Bucket(self, "TagTestBucket01", bucket_name="tag-test-bucket-001")
        s3_02 = s3.Bucket(self, "TagTestBucket02", bucket_name="tag-test-bucket-002")


app = core.App()
tag_sample_stack = TagSampleStack(app, "tag-sample")

# Add tags using the Tag class
core.Tag.add(tag_sample_stack, "Project", "TagTest")

app.synth()

When you run the above code, you'll see a warning that using Tag.add is deprecated, and it recommends using Tags.of(scope).add(k,v) instead.

[Warning at /tag-sample] The API @aws-cdk/core.Tag.add(scope,k,v) is deprecated: Use "Tags.of(scope).add(k,v)" instead. This API will be removed in the next major release