feat(elbv2): scaffold Elastic Load Balancing v2 — LoadBalancers + Tags

[vieiralucas]

Summary

First batch of ELBv2 (Application/Network/Gateway Load Balancer) support — picks up the Wave 4 roadmap slot after ECR + ECS shipped.

• New crate fakecloud-elbv2 wired into server under SigV4 service elasticloadbalancing. Wire protocol: AWS Query, XML responses (matching real ELBv2).
• 12 ops shipped this batch: CreateLoadBalancer, DescribeLoadBalancers, DeleteLoadBalancer, SetSubnets, SetSecurityGroups, SetIpAddressType, ModifyIpPools, AddTags, RemoveTags, DescribeTags, DescribeAccountLimits, DescribeSSLPolicies.
• All 3 LB types (application, network, gateway) — ARN prefix matches AWS conventions (app/, net/, gwy/); idempotent CreateLoadBalancer; cascade-delete listeners/rules on DeleteLoadBalancer; tags routing across every taggable resource.
• Smithy-exact validation: 1–32 char name, alphanumeric + hyphens, internal- prefix rejection, Type/Scheme/IpAddressType enum constraints — returns ValidationError with the AWS-shaped error envelope.

Introspection

• GET /_fakecloud/elbv2/load-balancers
• GET /_fakecloud/elbv2/target-groups
• GET /_fakecloud/elbv2/listeners
• GET /_fakecloud/elbv2/rules

SDKs

• TypeScript: Elbv2Client (fc.elbv2.getLoadBalancers() etc.)
• Python: Elbv2Client + _SyncElbv2Client + dataclass types
• Go/PHP/Java/Rust SDKs land alongside the next batch (ops they introspect aren't shipped yet)

Docs

• README service table + LocalStack comparison row
• website/content/local-elb.md landing page
• website/static/llms.txt updated
• Conformance audit map gains elasticloadbalancing + ECR/ECS entries

Roadmap

Subsequent batches: target groups + targets + health, listeners + rules, attributes + trust stores + capacity reservations, real in-process HTTP routing + ECS auto-register-target.

Test plan

• cargo test -p fakecloud-elbv2 — 7 unit tests pass
• cargo test -p fakecloud-conformance --test elbv2 — 12 Smithy-checksum-validated tests pass
• cargo build --tests workspace clean
• cargo clippy --workspace --all-targets -- -D warnings clean
• cargo fmt --all -- --check clean

---

Summary by cubic

Adds first batch of ELBv2 support (ALB/NLB/GWLB) for Load Balancers and Tags under SigV4 elasticloadbalancing. Ships 12 core ops with Smithy-accurate validation, SDKs, and introspection.

• New Features

  • New crate fakecloud-elbv2 (AWS Query, XML) wired into the server.
  • 12 ops: Create/Describe/Delete LoadBalancers; SetSubnets/SecurityGroups/IpAddressType; ModifyIpPools; Add/Remove/DescribeTags; DescribeAccountLimits/SSLPolicies.
  • Supports application, network, gateway types with correct ARN prefixes (app/, net/, gwy/); idempotent create; cascade-delete listeners/rules.
  • Strict validation (name rules, internal- prefix, enum constraints) returning AWS-shaped ValidationError.
  • Introspection: /_fakecloud/elbv2/{load-balancers,target-groups,listeners,rules}.
  • SDKs: TypeScript and Python Elbv2Client + types; testkit elbv2_client(); conformance wired via aws-sdk-elasticloadbalancingv2.
  • Tests/Docs/Models: 12 conformance tests + 7 unit; README service table updated; website/content/local-elb.md; added aws-models/elasticloadbalancingv2.json + service-map entry.

• Bug Fixes

  • Enforce IpAddressType validation in CreateLoadBalancer and SetSubnets via a shared helper (was only in SetIpAddressType).
  • Python SDK: ruff fixes and formatting in Elbv2Client code.
  • Docs: update website/static/llms.txt headline counts to 26 services / 1,810 ops.
  • Rust: format validate_ip_address_type helper.

^{Written for commit 0d472ab. Summary will update on new commits.}

[cubic-dev-ai]

3 issues found across 26 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="website/static/llms.txt">

<violation number="1" location="website/static/llms.txt:8">
P3: The updated service list now includes 26 services, but the nearby headline still says 23 services / 1,680 operations, so this section is internally inconsistent.</violation>
</file>

<file name="crates/fakecloud-elbv2/src/service.rs">

<violation number="1" location="crates/fakecloud-elbv2/src/service.rs:439">
P2: Validate `IpAddressType` in `CreateLoadBalancer`; invalid values are currently accepted and stored.</violation>

<violation number="2" location="crates/fakecloud-elbv2/src/service.rs:658">
P2: `SetSubnets` should validate `IpAddressType` before updating state.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[codecov]

Codecov Report

❌ Patch coverage is 57.86273% with 485 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
crates/fakecloud-elbv2/src/service.rs	67.51%	305 Missing ⚠️
crates/fakecloud-server/src/introspection.rs	0.00%	93 Missing ⚠️
crates/fakecloud-server/src/main.rs	0.00%	74 Missing ⚠️
crates/fakecloud-elbv2/src/state.rs	62.85%	13 Missing ⚠️

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