# CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

## Project Overview

`mxaccessgw` is the MXAccess Gateway: a gRPC service that gives modern (.NET, Go, Rust, Python, Java) clients full MXAccess parity without forcing them to load 32-bit MXAccess COM, run x86, or own an STA message pump.

The architecture is a two-process design — read `gateway.md` before making structural changes:

- **Gateway** (`src/MxGateway.Server`, .NET 10, x64): ASP.NET Core gRPC server. Owns the public API, sessions, auth, the Blazor dashboard, and the Galaxy Repository SQL browse RPCs. **Never instantiates MXAccess COM directly.**
- **Worker** (`src/MxGateway.Worker`, .NET Framework 4.8, **x86**): one process per session. Owns one MXAccess COM instance on a dedicated STA, pumps Windows messages, and converts COM events to protobuf.
- **IPC**: gateway↔worker uses one bidirectional named pipe per worker (`mxaccess-gateway-{gatewayPid}-{sessionId}`) with length-prefixed `WorkerEnvelope` protobuf frames. Gateway hosts the pipe server and launches the worker. **gRPC is not used inside the worker** — .NET Framework 4.8 doesn't have a first-class gRPC stack.
- **Contracts** (`src/MxGateway.Contracts`): multi-targets `net10.0;net48` and owns the `.proto` files (`mxaccess_gateway.proto`, `mxaccess_worker.proto`, `galaxy_repository.proto`). All other projects consume the generated types from here. Do not hand-edit anything under `Generated/`.

The worker must do all MXAccess COM calls on its dedicated STA thread, and the STA loop must pump Windows messages (`MsgWaitForMultipleObjectsEx` + `PeekMessage`/`DispatchMessage`) so MXAccess events deliver. A plain blocking queue on an STA is not enough.

## Build, Test, Run

```powershell
# Full solution build (gateway, worker, contracts, tests)
dotnet build src/MxGateway.sln

# Worker must be built x86 — the gateway looks for MxGateway.Worker.exe under bin\x86
dotnet build src/MxGateway.Worker/MxGateway.Worker.csproj -p:Platform=x86

# Gateway tests (no MXAccess required — uses FakeWorkerHarness)
dotnet test src/MxGateway.Tests/MxGateway.Tests.csproj
dotnet test src/MxGateway.Worker.Tests/MxGateway.Worker.Tests.csproj -p:Platform=x86

# Run gateway locally (defaults bound under MxGateway:* in src/MxGateway.Server/appsettings.json)
dotnet run --project src/MxGateway.Server/MxGateway.Server.csproj

# API-key admin CLI (same exe, "apikey" subcommand)
dotnet run --project src/MxGateway.Server/MxGateway.Server.csproj -- apikey create --display-name "dev" --scopes session,invoke,event,metadata,admin
```

Single test by name (xUnit `--filter`):

```powershell
dotnet test src/MxGateway.Tests/MxGateway.Tests.csproj --filter FullyQualifiedName~GatewayEndToEndFakeWorkerSmokeTests
```

Live MXAccess integration tests are **opt-in** because they need installed MXAccess COM and live provider state:

```powershell
$env:MXGATEWAY_RUN_LIVE_MXACCESS_TESTS = "1"
dotnet test src/MxGateway.IntegrationTests/MxGateway.IntegrationTests.csproj --filter FullyQualifiedName~WorkerLiveMxAccessSmokeTests
```

Live LDAP tests use `MXGATEWAY_RUN_LIVE_LDAP_TESTS=1`. See `docs/GatewayTesting.md` for the full opt-in matrix and `LiveMxAccessFactAttribute` / `LiveLdapFactAttribute` for the gating logic.

## Clients

Each language client is in `clients/<lang>/` with its own README. They all consume the shared `.proto` files in `src/MxGateway.Contracts/Protos`:

- `clients/dotnet`: `dotnet build clients/dotnet/MxGateway.Client.sln`
- `clients/python`: `python -m pip install -e ".[dev]"; python -m pytest`
- `clients/rust`: `cargo test --workspace; cargo clippy --workspace --all-targets -- -D warnings`
- `clients/java`: `gradle test` (Java 21)
- Go client lives alongside as `mxgw-go` in the cross-language matrix

End-to-end matrix runner (needs running gateway + worker + valid API key):

```powershell
$env:MXGATEWAY_API_KEY = "<api-key>"
powershell -ExecutionPolicy Bypass -File scripts/run-client-e2e-tests.ps1
```

## Repository-Specific Conventions

- **Build properties** (`src/Directory.Build.props`) enforce `Nullable=enable`, `TreatWarningsAsErrors=true`, latest analyzers, and `EnforceCodeStyleInBuild=true`. New warnings break the build — fix them, don't suppress unless the suppression has a narrow reason.
- **Style guides** in `docs/style-guides/` are authoritative. Follow `CSharpStyleGuide.md` for gateway/worker/.NET-client code: file-scoped namespaces, `sealed` by default, `Async` suffix on Task-returning methods, MXAccess-aligned names (`MxStatusProxy`, `ServerHandle`, `ItemHandle`, `HResult`).
- **MXAccess parity is the contract.** Don't "fix" surprising MXAccess behavior (e.g., `WriteSecured` failing before a value-bearing NMX body, distinct `OperationComplete` semantics, invalid-handle exceptions) unless the client explicitly opts into a non-parity mode. The installed MXAccess COM component is the baseline.
- **Don't synthesize events.** The gateway forwards only events the worker emits; it never invents `OperationComplete` from write completion or command replies.
- **One worker per session, one event subscriber per session** (v1). Multi-subscriber fan-out and reconnectable sessions are explicitly out of scope — see `docs/DesignDecisions.md`.
- **Gateway restart does not reattach orphan workers.** The first version terminates orphaned workers on startup; do not design code paths that assume reattachment.
- **No Blazor UI component libraries.** Dashboard uses local Bootstrap CSS/JS only — do not introduce MudBlazor, Radzen, FluentUI, etc.
- **Don't log secrets or full tag values by default.** API keys, passwords, `WriteSecured` payloads, and `AuthenticateUser` credentials must never reach logs. Value logging is opt-in and redacted.
- **Generated code** under `src/MxGateway.Contracts/Generated/`, `clients/*/generated*/`, `clients/python/src/mxgateway/generated/`, etc., is build output. Don't hand-edit. To regenerate, build the contracts project (`dotnet build src/MxGateway.Contracts/MxGateway.Contracts.csproj`) or run the per-client generation step in that client's README.
- **Documentation style** (`StyleGuide.md`): PascalCase filenames, no marketing language, present tense, explain *why* not *what*.
- **Update docs in the same change as the source.** When public APIs, contracts, configuration, build steps, security behavior, event shapes, value conversion, status mapping, or lifecycle rules change, the affected docs (`gateway.md`, `docs/`, client READMEs, design docs) must change in the same commit. Don't leave stale prose describing old behavior.

## Source Update Workflow

When source code changes, build and test the affected component before reporting work done. If the change crosses component boundaries, build each affected component — don't rely on a single top-level build:

| Changed area | Required verification |
|---|---|
| Contracts or `.proto` files | regenerate generated code, then build gateway, worker, and every generated client touched by the contract |
| Gateway server, sessions, workers, gRPC, dashboard, metrics | `dotnet build src/MxGateway.Server` and run affected gateway / fake-worker tests |
| Worker IPC, STA, MXAccess, conversion | `dotnet build src/MxGateway.Worker -p:Platform=x86` and run worker tests |
| .NET client | `dotnet build clients/dotnet/MxGateway.Client.sln` and run its tests |
| Go client | `gofmt`, `go build ./...`, `go test ./...` from `clients/go` |
| Rust client | `cargo fmt`, `cargo check --workspace`, `cargo test --workspace`, `cargo clippy --all-targets -- -D warnings` from `clients/rust` |
| Python client | `python -m pytest` from `clients/python` |
| Java client | `gradle test` from `clients/java` |
| Integration tests | run only when MXAccess COM, provider state, and external services are available; otherwise document why skipped |

## Design Sources To Consult Before Non-Trivial Changes

- `gateway.md` — top-level architecture, command/event surface, IPC envelope, STA thread model, fault handling.
- `glauth.md` — local LDAP server (GLAuth on `localhost:3893`, base DN `dc=lmxopcua,dc=local`) used for dev authn. Pre-provisioned users (`admin/admin123`, `readonly/readonly123`, etc.) and the role→capability mapping live there.
- `docs/DesignDecisions.md` — v1 choices (MXAccess COM target `LMXProxyServerClass` from `C:\Program Files (x86)\ArchestrA\Framework\Bin\ArchestrA.MXAccess.dll`, API-key-in-SQLite auth, fail-fast event backpressure, etc.).
- `docs/GatewayProcessDesign.md`, `docs/MxAccessWorkerInstanceDesign.md`, `docs/WorkerFrameProtocol.md`, `docs/WorkerProcessLauncher.md` — detailed component designs.
- `docs/GatewayConfiguration.md` — full `MxGateway:*` options bound by `GatewayOptions` and validated at startup by `GatewayOptionsValidator`.
- `docs/GatewayTesting.md` — fake worker harness, live MXAccess smoke, parity matrix, cross-language smoke matrix.
- `docs/ToolchainLinks.md` — installed compiler/SDK paths on this dev box (.NET 10.0.201, Go 1.26.2, Rust 1.95, Python 3.12.10, Temurin 21, protoc 34.1, etc.).

External analysis sources referenced by design docs:

- `C:\Users\dohertj2\Desktop\mxaccess` — MXAccess analysis project. Key files: `docs/MXAccess-Public-API.md` (COM class, ProgID, CLSID, method list, event signatures, `MxDataType`, `MxStatus`, `MXSTATUS_PROXY`), `docs/MXAccess-Reverse-Engineering.md` (installed runtime path, x86 COM constraints), `docs/Current-Sprint-State.md` (parity gaps), `src/MxTraceHarness/` (x86 harness using the real COM interop), `captures/` and `analysis/` (observed native behavior).
- `C:\Users\dohertj2\Desktop\lmxopcua\gr` — Galaxy Repository (`ZB` SQL DB) notes. Key files: `connectioninfo.md`, `layout.md`, `schema.md`, `queries/hierarchy.sql`, `queries/attributes.sql`, `queries/attributes_extended.sql`, `queries/change_detection.sql`. Connection is SQL Server `localhost`, database `ZB`, Windows Auth.

## Authentication

Gateway gRPC clients authenticate with an API key in metadata: `authorization: Bearer mxgw_<key-id>_<secret>`. Keys are stored hashed (with a peppered SHA) in a gateway-owned SQLite DB (default `C:\ProgramData\MxGateway\gateway-auth.db`). Scopes (`session`, `invoke`, `event`, `metadata`, `admin`) gate specific RPCs; missing → `Unauthenticated`, insufficient → `PermissionDenied`. The `apikey` subcommand on the server exe manages keys; see `src/MxGateway.Server/Security/Authentication/`.

Dashboard auth is LDAP-backed (separate from the gRPC API-key model). `/login` binds against `MxGateway:Ldap` and maps the user's LDAP groups to `Admin` or `Viewer` via `MxGateway:Dashboard:GroupToRole`, then issues an HTTP-only secure `__Host-MxGatewayDashboard` cookie. SignalR hubs at `/hubs/{snapshot,alarms,events}` accept either the cookie or a 30-minute bearer minted at `/hubs/token`. `Dashboard:AllowAnonymousLocalhost` bypasses auth on loopback when enabled.

## Process / Platform Notes

- Working tree is on Windows (`C:\Users\dohertj2\Desktop\mxaccessgw`). PowerShell is the native shell for tooling commands; bash is fine for git/grep/find.
- The worker reference to `ArchestrA.MXAccess.dll` uses an absolute `HintPath` to `C:\Program Files (x86)\ArchestrA\Framework\Bin\ArchestrA.MXAccess.dll`. The worker only builds where MXAccess is installed (this dev box).
- The repo is not a git repository at the top level — there's no `.git` directory in the working tree.