feat(ec2): network interface definitions for launch templates

[pasiorovuo]

This PR implements basic functionality for defining network interfaces as part of Launch Template.

Issue # (if applicable)

Fixes #14494

Reason for this change

Current Launch Template L2 is missing the ability to define multiple interfaces, their subnets etc. This functionality is required in advanced scenarios where instances need multiple public IP addresses or need to be multi-homed etc.

Description of changes

Multiple new types have been introduced in packages/aws-cdk-lib/aws-ec2/lib/launch-template.ts. Many of them are just renamed extends of the ec2-generated types. This made sense as the Cloudformation type definition is suitable, but I'm a bit uncertain if this violates the design requirement Do not “leak” the details or types of the CFN layer when defining your construct API.

Main type is NetworkInterface which defines the attributes for the interfaces. Additional changes are in LaunchTemplate constructor to accommodate the new functionality.

README has been updated to include a simple usage example.

Description of how you validated changes

A single test has been added. I have also verified the implementation by creating stacks in different configurations and deployed them. There too many combinations to check them all, so only a subset has been tested, unfortunately.

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[aws-cdk-automation]

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[pasiorovuo]

I do not know what the failing check is about.

[aws-cdk-automation]

This PR cannot be merged because it has conflicts. Please resolve them. The PR will be considered stale and closed if it remains in an unmergeable state.

[aws-cdk-automation]

AWS CodeBuild CI Report

• CodeBuild project: AutoBuildv2Project1C6BFA3F-wQm2hXv2jqQv
• Commit ID: 8be843b
• Result: SUCCEEDED
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[pasiorovuo]

This seems to be overlapping in parts with #28901. If it would be accepted, I could update this PR to account for the new types etc. introduced by it.

[chenhe95]

I think that if networkInterfaces is defined, we should not be providing anything in securityGroupIds. Since the options provided in securityGroupsToken are not used at all unless props.networkInterfaces is undefined and props.associatePublicIpAddress is defined

On line securityGroupIds: networkInterfaces ? undefined : securityGroupsToken, right above

[chenhe95]

Would it be possible to also have unit tests in

aws-cdk/packages/aws-cdk-lib/aws-ec2/test/launch-template.test.ts

Line 4 in 7b2a653

CfnInstanceProfile,

that have cases for when different network interface options are provided and also a verification that when props.associatePublicIpAddress is incompatible with props.networkInterfaces, the correct error is thrown?

[chenhe95]

I was never able to figure out how these defaults are resolved since the AWS documentation doesn't have any info
https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-ec2-launchtemplate-privateipadd.html

PrivateIpAddresses

    One or more private IPv4 addresses.

    Required: No

    Type: Array of [PrivateIpAdd](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-ec2-launchtemplate-privateipadd.html)

    Update requires: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

[chenhe95]

Hi Pasi. Thanks for looking into this! I actually had the exact same issue #30891 as the one you're trying to solve. Your PR looks very similar to my local prototype with the differences being in how security group IDs are handled and how the unit tests are done. I was also not sure how AWS determines default behaviors when input fields are left undefined. Left comments on those parts.

Nice work!

[chenhe95]

Hi Pasi! I am wondering if this ticket is still being worked on, since I am very invested in getting launch templates to be more configurable
Thank you for all the work so far!