fix server_native callback wakeups and request uri handling

[kingwill101]

Summary

• restore absolute HttpRequest.uri / requestedUri reconstruction for server_native bridge requests so the request scheme remains available to framework code
• replace the idle backoff loop in the default native callback path with callback-driven queue draining so queued direct frames wake Dart immediately
• extend native callback regression coverage for HttpRequest compatibility and bridge URI behavior

Why

A recent performance refactor left two regressions on the issue #10 branch:

• BridgeHttpRequest.uri became origin-form for normal requests, which cleared httpRequest.uri.scheme and broke downstream consumers that derive request scheme from HttpRequest.uri
• the default native callback transport still relied on exponential sleep while directRequestCallback was unset, so the first queued frame after idle could sit until the next poll window expired

Impact

• preserves Request.scheme / X-Forwarded-Proto behavior for server_native requests again
• removes avoidable tail latency from the default nativeCallback: true direct transport
• keeps the isolate-scaling fix for issue Performance bottleneck when scaling NativeHttpServer across multiple isolates (shared: true) #10 intact while closing the review regressions found on top of it

Root Cause

The branch that reduced isolate-scaling overhead switched callback request URI materialization to a relative URI and changed the direct queue drain loop to idle/backoff polling without wiring Rust's existing direct callback wake signal into Dart.

Validation

• dart analyze packages/server_native/lib/src/bridge/bridge_runtime_request.dart packages/server_native/lib/src/bridge/bridge_runtime_request_uri.dart packages/server_native/lib/src/server_boot_proxy_direct.dart packages/server_native/test/bridge_runtime_test.dart packages/server_native/test/serve_ffi_http_test.dart
• dart test packages/server_native/test/bridge_runtime_test.dart
• dart test test/serve_ffi_http_test.dart from packages/server_native
• dart test test/ffi_http_server_test.dart --plain-name "NativeHttpServer reconstructs requestedUri from forwarded headers" from packages/server_native

Issue #10 Repro Check

Local wrk run on an 8-logical-CPU Linux host with -t8 -c200 -d15s:

Case	req/s	p50	p99
dart:io x1	18652.21	10.66 ms	15.19 ms
dart:io x8	37173.81	4.74 ms	18.77 ms
server_native x1	29178.05	6.73 ms	10.40 ms
server_native x8	46046.45	3.94 ms	12.18 ms

That reproducer no longer shows the flat multi-isolate behavior from #10; server_native scaled by about 57.8% on this host.

Fixes #10

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Project	Deployment	Actions	Updated (UTC)
routed	Ready	Preview, Comment	Apr 9, 2026 7:23pm

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[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:property_testing	0.3.2	already published at pub.dev
package:routed	0.3.3	(error) pubspec version (0.3.3) and changelog (0.3.4) don't agree
package:routed_auth	0.1.0	ready to publish	routed_auth-v0.1.0
package:routed_hotwire	0.1.2	already published at pub.dev
package:routed_io	0.1.0	ready to publish	routed_io-v0.1.0
package:routed_testing	0.3.3	(error) pubspec version (0.3.3) and changelog (0.3.2) don't agree
package:server_native	0.1.3+1	(error) pubspec version (0.1.3+1) and changelog (null) don't agree
package:server_testing	0.3.3	already published at pub.dev
package:server_testing_shelf	0.3.2	already published at pub.dev

Documentation at https://github.com/dart-lang/ecosystem/wiki/Publishing-automation.

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[coderabbitai]

✅ Created PR with unit tests: #13

[kartikey321]

@kingwill101 Great work on the pr. Love your work . Just had a question what if you used actix or even directly io_uring instead of tokyo. Can server native be scaled even more , as the more costly part of it is the boundary between dart and rust, so i don't think that can be optimised.

I was working on a proof of concept dart with hot paths and http parsing in zig from io_uring in linux.
had gotten initial benchmarks as quite promising on HttpArena comparison between dart io and dart zig done on a 64 core vps

Test	Connections	dart:io RPS	dart-zig RPS	Relative
baseline	512	601,780	1,353,265	~2.25x
baseline	4096	583,020	1,665,927	~2.86x
pipelined	512	998,153	1,364,400	~1.37x
pipelined	4096	997,674	1,477,162	~1.48x

• This is an initial PoC snapshot for directional signal.
• Current PoC is not memory-optimized yet; memory tuning is pending.

I even raised a discussion in the dart sdk about a custom server specific runtime. It would be great if dart eventually progresses on the server side and makes it more performant

dart-lang/sdk#63352