aws/aws-cdk

aws-applicationautoscaling: Target Tracking Scaling Policy does not support account for custom metric

Open

#36401 opened on Dec 16, 2025

View on GitHub
 (2 comments) (0 reactions) (0 assignees)TypeScript (10,710 stars) (3,530 forks)batch import
@aws-cdk/aws-applicationautoscalingeffort/smallfeature-requestgood first issuep2

Description

Describe the bug

Target Scaling Policy does not return the account information from the metric so cross account metric cannot be used.

https://github.com/aws/aws-cdk/blob/244c02de488a9dfe7dad9eca1e9bb301863216bc/packages/aws-cdk-lib/aws-applicationautoscaling/lib/target-tracking-scaling-policy.ts#L170

Regression Issue

  • Select this option if this issue appears to be a regression.

Last Known Working CDK Library Version

No response

Expected Behavior

The renderCustomMetric function the target tracking policy should return the account from the metric as well

https://github.com/aws/aws-cdk/blob/244c02de488a9dfe7dad9eca1e9bb301863216bc/packages/aws-cdk-lib/aws-applicationautoscaling/lib/target-tracking-scaling-policy.ts#L162C10-L162C28

Current Behavior

The account information is never fetched from the metric so it default to the current account when creating it

Reproduction Steps

Create a Target Tracking Policy using a Custom Metric and specify the a different account for the metric and it will be ignored

Possible Solution

No response

Additional Information/Context

No response

AWS CDK Library version (aws-cdk-lib)

2.223.0

AWS CDK CLI version

2.1031.2

Node.js Version

22.9.0

OS

Amazon Linux 2023

Language

Python

Language Version

3.11

Other information

No response

Contributor guide

Tech stack
typescriptaws
Domain
backendcloud
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
TypeScriptAWS CDKUnderstanding of CloudFormation metrics
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40
Research direction
The bug is located in the renderCustomMetric function in the file packages/aws cdk lib/aws applicationautoscaling/lib/target tracking scaling policy.ts (lines 162-170). The issue is that the function currently doesn't include the account from the metric, so cross account metrics default to the current account. A contributor should examine how the metric's account property can be accessed and modify the rendering logic to include it. Additionally, ensure that any other functions that generate metric configurations also account for this property. Check the linked file and the autoscaling documentation for reference.