[seeeun-cho]

Description

Tags defined on the launch template (tags, runner_ec2_tags) are not part of the CreateFleet and RunInstances requests made by the scale-up and pool Lambdas, which only carry the module-owned ghr:* tags. Organization policies that evaluate aws:RequestTag (for example an SCP that denies ec2:RunInstances unless mandatory tags are present) therefore reject every launch, even when the tags are set in Terraform.

This change (following the review suggestion):

• describes the $Default version of the launch template used for the request and reads its instance and volume tag specifications;
• merges them into the request tag specifications on both the CreateFleet and RunInstances paths (the fleet tags use the instance tags);
• applies module-owned ghr:* tags last, so they take precedence;
• falls back to the module-owned tags, with a warning, if the launch template cannot be described.

There are no Terraform changes: no new environment variable, and the scale-up role already has ec2:DescribeLaunchTemplateVersions.

Behavior note: each launch now makes one extra DescribeLaunchTemplateVersions call (two when the on-demand failover retries). Three existing failover tests asserted the position of CreateFleet in the overall call order, so their ordinals were updated.

Not covered: the experimental modules/compute-providers path, which has its own tag semantics. Happy to extend it if maintainers prefer.

Test Plan

• Added unit tests in runners.test.ts: the $Default launch template version is read, template tags are merged into the instance, volume and fleet tags of CreateFleet, merged into RunInstances, module-owned ghr:* tags take precedence, and fallback when the template cannot be described. The merge tests fail without the change to runners.ts.
• All EC2 library tests pass (343/343). ESLint and Prettier are clean.
• Not yet tested against a live AWS account or an SCP.

Related Issues

None found.

🤖 Generated with Claude Code

[edersonbrilhante]

@seeeun-cho How about describe the launch template and get the tags specifications and merge the tags defined in ts code with the tags defined in the tf code?

[seeeun-cho]

Hi @edersonbrilhante, thanks for the suggestion.
Reworked: The Lambda now retrieves the launch template's default version and merges its instance and volume tag specifications into the CreateFleet/RunInstances request tags. Existing ghr:* tags take precedence. If the launch template cannot be described, the Lambda falls back to ghr:* tags only.