Fix HTTP codegen infinite loop for [AsParameters] + [ReadAggregate]/[WriteAggregate]

[jeremydmiller]

Problem

A hybrid message-handler / HTTP endpoint that uses Marten with [ReadAggregate] (or [WriteAggregate]), brings the aggregate identifier through a route argument, and binds the request with [AsParameters] sends HTTP code generation into an infinite loop (StackOverflow), so the app can't boot.

Reproduction (the reported shape):

public record GetJourney([FromRoute] Guid JourneyId);

public static class GetJourneyHandler
{
    [WolverineGet("/api/example-event-sourcing/journey/{journeyId:guid}")]
    public static JourneyResponse Handle([AsParameters] GetJourney query, [ReadAggregate] Journey journey)
        => JourneyResponse.From(journey);
}

Root cause (all in code generation)

The cyclic Next chain that overflows the stack:

AsParametersBindingFrame.GenerateCode
 → TagHttpHandlerFrame → OpenMartenSessionFrame → CreateMessageContextWithMaybeTenantFrame
 → ReadHttpFrame.GenerateCode
 → AsParametersBindingFrame.GenerateCode   ← cycles forever

AsParametersBindingFrame owns the route-read ReadHttpFrame for the id and generates it inline (as a constructor argument of the bound query object). The [ReadAggregate]/[WriteAggregate] identity resolution searches with ValueSource.Anything, and HttpChain.TryFindVariable returned that same owned route Variable. The aggregate-loader frame therefore depended on it, so MethodFrameArranger pulled the owned ReadHttpFrame into the method chain and gave it a Next — and generating it inline re-entered the whole chain, forever.

(This only happens with [AsParameters]: a plain route param or [FromQuery] id binds to a standalone frame that nothing re-embeds, so there's no cycle — which is why the existing /orders/latest/{id} and …/from-query endpoints work.)

Fix

When an endpoint binds an [AsParameters] object, a ValueSource.Anything lookup for a value that lives on that object now resolves to a member access on the bound object (query.Id) instead of the route/query read frame that AsParametersBindingFrame owns and generates inline. The aggregate loader then depends on the [AsParameters] object (a normal standalone frame in the chain) rather than on the inline-generated read frame — no cyclic Next.

• New HttpChain.AsParametersVariable, set by the [AsParameters] strategy.
• HttpChain.TryFindVariable short-circuits to new MemberAccessVariable(AsParametersVariable, member) for matching members, scoped to ValueSource.Anything so specific-source (RouteValue/FromQuery/Header) bindings are untouched.

Generated code is now straightforward and correct:

var getLatestOrderQuery = new GetLatestOrderQuery(Id);
var order = await documentSession.Events.FetchLatest<Order>(getLatestOrderQuery.Id, httpContext.RequestAborted);

Tests

• New end-to-end test happy_path_reading_aggregate_with_id_from_asparameters_route exercising the route-id-through-[AsParameters] + [ReadAggregate] combination (would hang on regression), plus the sample endpoint in WolverineWebApi.
• Entire Wolverine.Http.Tests suite run locally: 779 passed, 10 skipped, 0 failed — no regressions in the regression-prone HTTP codegen.

🤖 Generated with Claude Code