mirror of
https://github.com/headroomlabs-ai/headroom.git
synced 2026-08-27 14:17:10 -04:00
## Description
Adds a Rust-only `headroom-simulators` workspace crate: a deterministic
local upstream simulator service for Headroom proxy and pipeline
validation. It supplies configurable stubs plus bottled provider-shaped
responses for supported provider/path surfaces without calling real
LLMs.
## Type of Change
- [x] Bug fix (non-breaking change that fixes an issue)
- [x] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update
- [ ] Performance improvement
- [ ] Code refactoring (no functional changes)
## Changes Made
- Added `crates/headroom-simulators` Rust crate with library and
`headroom-simulators` binary.
- Added clean domain classification for supported surfaces: Anthropic
`/v1/messages`, OpenAI chat/responses/conversations, Bedrock
invoke/stream routes, Vertex raw/stream predict, health, and generic
fallback.
- Added JSON-configured stub matching by method, path, body substring,
and JSON pointer.
- Added bottled provider-shaped JSON, SSE, and Bedrock EventStream
responses for unconfigured requests.
- Added a container `Dockerfile` and README for local/GitHub Actions
usage.
- Added unit and HTTP integration tests for defaults, configured stubs,
SSE, Vertex, and Bedrock EventStream behavior.
- Added proxy-level simulator-backed E2E tests that run Headroom against
the simulator across Anthropic, OpenAI Chat, OpenAI Responses, OpenAI
Conversations, Bedrock invoke/converse/streaming, Vertex raw/stream
predict, and upstream health.
- Added simulator-backed provider error-path E2E coverage for OpenAI
429, Anthropic 529, Bedrock 502, and Vertex 503 responses flowing
through Headroom unchanged.
- Added Headroom-owned preflight error E2E coverage proving Bedrock
missing credentials and invalid Vertex envelopes stop inside the proxy
instead of silently falling through to the simulator/provider.
- Fixed direct Rust `headroom-core` binaries/tests on Windows so Magika
initializes ONNX Runtime via `ort::init_from` from an explicit pip
`onnxruntime` library path, with fail-fast fallback only when no safe
runtime is discoverable.
- Added a Rust CI `simulator-e2e` matrix for `ubuntu-latest`,
`macos-latest`, and `windows-latest` that runs `cargo test -p
headroom-proxy --test e2e_simulators`.
- Gated dynamic Magika `Path`/`PathBuf` imports to Windows and x86_64
macOS so Linux clippy does not see unused dynamic-ORT-only imports.
## Testing
- [ ] Unit tests pass (`pytest`)
- [ ] Linting passes (`ruff check .`)
- [ ] Type checking passes (`mypy headroom`)
- [x] New tests added for new functionality
- [x] Manual testing performed
### Test Output
cargo fmt --all -- --check
# passed
cargo clippy --workspace -- -D warnings
# passed
$env:ORT_DYLIB_PATH=$null
cargo test -p headroom-core transforms::magika_detector::tests:: --lib
# 17 passed, 0 failed; Magika initialized from discovered pip
onnxruntime DLL
$env:ORT_DYLIB_PATH=$null
cargo test --workspace
# passed
gitleaks protect --staged --no-banner --redact
# no leaks found
gitleaks git --log-opts="headroomlabs/main..HEAD" --no-banner --redact
# 5 commits scanned; no leaks found
## Real Behavior Proof
- **Environment:** Windows PowerShell, Rust toolchain `1.95.0`, clean
worktree from `headroomlabs/main` at `9bacf481`.
- **Exact simulator command / steps:**
- `cargo run -p headroom-simulators -- --listen 127.0.0.1:8789`
- Point Headroom proxy upstream at `http://127.0.0.1:8789` for local
deterministic provider responses.
- Use optional `--config path/to/simulator.json` to bind exact request
fixtures.
- **Observed simulator result:**
- OpenAI chat default returns `chat.completion` shape.
- OpenAI Responses stream returns named SSE events.
- Vertex raw predict returns Anthropic message shape.
- Bedrock stream can return binary `application/vnd.amazon.eventstream`
bytes.
- Configured stubs override bottled defaults.
- **Observed Magika result:**
- Direct Rust `headroom-core` tests pass with `ORT_DYLIB_PATH` unset.
- Magika discovers the installed pip `onnxruntime.dll`, loads it via
`ort::init_from`, and only falls back if no safe runtime is available.
- **Not tested:**
- No live provider calls; simulator behavior is intentionally offline
and deterministic.
## Review Readiness
- [x] I have performed a self-review
- [x] This PR is ready for human review
## Checklist
- [x] My code follows the project's style guidelines
- [x] I have performed a self-review of my code
- [x] I have commented my code, particularly in hard-to-understand areas
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [ ] I have updated the CHANGELOG.md if applicable
## Screenshots (if applicable)
N/A
## Additional Notes
No CHANGELOG entry was added because this introduces a developer/CI
simulator crate plus a Windows direct-Rust Magika runtime fix, without
changing shipped Python package behavior. The simulator intentionally
does not include a lightweight fallback LLM in this slice; unbound
inputs receive deterministic bottled responses so tests stay
reproducible and offline.
11 lines
340 B
Docker
11 lines
340 B
Docker
FROM rust:1.96-slim AS build
|
|
WORKDIR /workspace
|
|
COPY . .
|
|
RUN cargo build --release -p headroom-simulators
|
|
|
|
FROM debian:bookworm-slim
|
|
RUN useradd --create-home --uid 10001 headroom
|
|
COPY --from=build /workspace/target/release/headroom-simulators /usr/local/bin/headroom-simulators
|
|
USER headroom
|
|
EXPOSE 8789
|
|
ENTRYPOINT ["headroom-simulators"]
|