scadalink-design/code-reviews/README.md

# Code Reviews

Comprehensive, per-module code reviews of the ScadaLink codebase. Each module (one
buildable project under `src/`) has its own folder containing a `findings.md`. This
README is the aggregated index — the single place to see all outstanding work.

> Generated by `regen-readme.py` from the per-module `findings.md` files. Do not
> edit by hand — edit the findings files and re-run the script.

## How it works

- Reviews are performed one module at a time against a fixed checklist.
- Every finding is recorded in the module's `findings.md` with a severity and status.
- Findings are **never deleted** — they are closed by changing their status, keeping
  a full audit trail.
- This README aggregates every **pending** finding (`Open` / `In Progress`) across all
  modules.

See **[REVIEW-PROCESS.md](REVIEW-PROCESS.md)** for the full procedure: the review
checklist, severity definitions, finding format, and how to mark items resolved.

## Layout

```
code-reviews/
├── README.md            # this file — process overview + pending findings
├── REVIEW-PROCESS.md     # how to perform a review and track findings
├── regen-readme.py       # regenerates this README from the findings files
├── _template/findings.md # copy-this template for a module review
└── <Module>/findings.md  # one folder per src/ project
```

## Baseline review — 2026-05-16

All 19 modules were reviewed at commit `9c60592` (241 findings: 6 Critical, 46 High,
100 Medium, 89 Low). The tables below track what remains **open** as findings are
resolved and re-triaged; findings discovered after the baseline are appended to their
module file and counted in **Total**.

| Severity | Open findings |
|----------|---------------|
| Critical | 0 |
| High | 8 |
| Medium | 20 |
| Low | 27 |
| **Total** | **55** |

## Module Status

| Module | Last reviewed | Commit | Open (C/H/M/L) | Open | Total |
|--------|---------------|--------|----------------|------|-------|
| [CLI](CLI/findings.md) | 2026-05-16 | `9c60592` | 0/0/1/2 | 3 | 16 |
| [CentralUI](CentralUI/findings.md) | 2026-05-16 | `9c60592` | 0/1/2/3 | 6 | 25 |
| [ClusterInfrastructure](ClusterInfrastructure/findings.md) | 2026-05-16 | `9c60592` | 0/0/1/1 | 2 | 10 |
| [Commons](Commons/findings.md) | 2026-05-16 | `9c60592` | 0/0/0/2 | 2 | 14 |
| [Communication](Communication/findings.md) | 2026-05-16 | `9c60592` | 0/1/1/2 | 4 | 15 |
| [ConfigurationDatabase](ConfigurationDatabase/findings.md) | 2026-05-16 | `9c60592` | 0/0/2/1 | 3 | 14 |
| [DataConnectionLayer](DataConnectionLayer/findings.md) | 2026-05-16 | `9c60592` | 0/1/2/1 | 4 | 17 |
| [DeploymentManager](DeploymentManager/findings.md) | 2026-05-16 | `9c60592` | 0/1/1/1 | 3 | 17 |
| [ExternalSystemGateway](ExternalSystemGateway/findings.md) | 2026-05-16 | `9c60592` | 0/1/1/1 | 3 | 17 |
| [HealthMonitoring](HealthMonitoring/findings.md) | 2026-05-16 | `9c60592` | 0/0/1/3 | 4 | 16 |
| [Host](Host/findings.md) | 2026-05-16 | `9c60592` | 0/0/1/3 | 4 | 15 |
| [InboundAPI](InboundAPI/findings.md) | 2026-05-16 | `9c60592` | 0/0/3/1 | 4 | 17 |
| [ManagementService](ManagementService/findings.md) | 2026-05-16 | `9c60592` | 0/1/1/2 | 4 | 17 |
| [NotificationService](NotificationService/findings.md) | 2026-05-16 | `9c60592` | 0/2/1/2 | 5 | 18 |
| [Security](Security/findings.md) | 2026-05-16 | `9c60592` | 0/0/2/2 | 4 | 15 |
| [SiteEventLogging](SiteEventLogging/findings.md) | 2026-05-16 | `9c60592` | 0/0/0/0 | 0 | 11 |
| [SiteRuntime](SiteRuntime/findings.md) | 2026-05-16 | `9c60592` | 0/0/0/0 | 0 | 16 |
| [StoreAndForward](StoreAndForward/findings.md) | 2026-05-16 | `9c60592` | 0/0/0/0 | 0 | 14 |
| [TemplateEngine](TemplateEngine/findings.md) | 2026-05-16 | `9c60592` | 0/0/0/0 | 0 | 14 |

## Pending Findings

Every `Open` / `In Progress` finding across all modules, highest severity first.
Resolved findings drop off this list but remain recorded in their module's
`findings.md` (see [REVIEW-PROCESS.md](REVIEW-PROCESS.md) §4–§5). Full detail —
description, location, recommendation — lives in the module's `findings.md`.

### Critical (0)

_None open._

### High (8)

| ID | Module | Title |
|----|--------|-------|
| CentralUI-020 | [CentralUI](CentralUI/findings.md) | Idle-session redirect never fires: `SessionExpiry` polls a frozen auth-state snapshot |
| Communication-012 | [Communication](Communication/findings.md) | gRPC client factory ignores the endpoint on a cache hit, breaking NodeA→NodeB stream failover |
| DataConnectionLayer-014 | [DataConnectionLayer](DataConnectionLayer/findings.md) | DCL-012 security warning is never logged in production: `RealOpcUaClient` is created without a logger |
| DeploymentManager-015 | [DeploymentManager](DeploymentManager/findings.md) | Site-query reconciliation marks a deployment `Success` but skips instance-state and snapshot updates |
| ExternalSystemGateway-015 | [ExternalSystemGateway](ExternalSystemGateway/findings.md) | `MaxRetries == 0` is buffered as "retry forever", contradicting the ExternalSystemGateway-004 "never retry" claim |
| ManagementService-014 | [ManagementService](ManagementService/findings.md) | HandleQueryDeployments bypasses site-scope enforcement |
| NotificationService-014 | [NotificationService](NotificationService/findings.md) | OAuth2 token-fetch failure escapes `DeliverBufferedAsync`; a permanently-broken config is retried forever |
| NotificationService-015 | [NotificationService](NotificationService/findings.md) | Unclassified exceptions (OAuth2 token fetch, non-cancellation OCE) escape `SendAsync` to the calling script |

### Medium (20)

| ID | Module | Title |
|----|--------|-------|
| CLI-014 | [CLI](CLI/findings.md) | `update` commands require "core" fields, making partial updates impossible |
| CentralUI-021 | [CentralUI](CentralUI/findings.md) | `DebugView` stream callback mutates `Dictionary` off the render thread |
| CentralUI-022 | [CentralUI](CentralUI/findings.md) | `Deployments` push handler fires `InvokeAsync` with no disposal guard |
| ClusterInfrastructure-009 | [ClusterInfrastructure](ClusterInfrastructure/findings.md) | `DownIfAlone` is an inert configuration knob — never consumed by the HOCON builder |
| Communication-013 | [Communication](Communication/findings.md) | Site gRPC address changes are never applied; `RemoveSiteAsync` has no production caller |
| ConfigurationDatabase-012 | [ConfigurationDatabase](ConfigurationDatabase/findings.md) | Inbound-API `ApiKey.KeyValue` bearer credential stored in plaintext |
| ConfigurationDatabase-013 | [ConfigurationDatabase](ConfigurationDatabase/findings.md) | Secret-column encryption silently falls back to an ephemeral (throwaway) key |
| DataConnectionLayer-015 | [DataConnectionLayer](DataConnectionLayer/findings.md) | Initial-connect failures never trigger failover; an unreachable primary at startup never tries the backup |
| DataConnectionLayer-016 | [DataConnectionLayer](DataConnectionLayer/findings.md) | `HandleSubscribeCompleted` reports `SubscribeTagsResponse` success even on a connection-level subscribe failure |
| DeploymentManager-016 | [DeploymentManager](DeploymentManager/findings.md) | Reconciled prior record keeps its stale `RevisionHash` |
| ExternalSystemGateway-016 | [ExternalSystemGateway](ExternalSystemGateway/findings.md) | `ConfigureHttpClientDefaults` applies the ESG connection cap to every `HttpClient` in the host process |
| HealthMonitoring-015 | [HealthMonitoring](HealthMonitoring/findings.md) | Heartbeat-registered site is left with a year-0001 `LastReportReceivedAt` |
| Host-012 | [Host](Host/findings.md) | `down-if-alone` hard-coded in HOCON; `ClusterOptions.DownIfAlone` is never read |
| InboundAPI-014 | [InboundAPI](InboundAPI/findings.md) | `ReturnDefinition` is loaded but never used; script return value is unshaped/unvalidated |
| InboundAPI-015 | [InboundAPI](InboundAPI/findings.md) | `ForbiddenApiChecker` is purely textual and is bypassable via reflection reachable without a forbidden namespace token |
| InboundAPI-016 | [InboundAPI](InboundAPI/findings.md) | Routed `Route.To().Call()` invocations are not bound by the method timeout |
| ManagementService-015 | [ManagementService](ManagementService/findings.md) | HandleSetInstanceOverrides applies overrides non-atomically |
| NotificationService-016 | [NotificationService](NotificationService/findings.md) | `AuthenticateAsync` silently sends unauthenticated for an unknown auth type or empty credentials |
| Security-012 | [Security](Security/findings.md) | Partial LDAP failure during login yields a roleless authenticated session |
| Security-014 | [Security](Security/findings.md) | `RefreshToken` re-issues a token without checking the idle timeout |

### Low (27)

| ID | Module | Title |
|----|--------|-------|
| CLI-015 | [CLI](CLI/findings.md) | `Component-CLI.md` command surface has drifted again in two places |
| CLI-016 | [CLI](CLI/findings.md) | `WriteAsTable` derives columns from the first array element only |
| CentralUI-023 | [CentralUI](CentralUI/findings.md) | Residual bare `catch {}` blocks swallow JS interop errors |
| CentralUI-024 | [CentralUI](CentralUI/findings.md) | Claim lookups use magic strings instead of `JwtTokenService` constants |
| CentralUI-025 | [CentralUI](CentralUI/findings.md) | `SessionExpiry` polling/redirect path has no test coverage |
| ClusterInfrastructure-010 | [ClusterInfrastructure](ClusterInfrastructure/findings.md) | Validator does not enforce `DownIfAlone = true` despite the design doc requiring it |
| Commons-013 | [Commons](Commons/findings.md) | `DynamicJsonElement.TryGetIndex` rejects non-`int` index values |
| Commons-014 | [Commons](Commons/findings.md) | `OpcUaEndpointConfigSerializer.Deserialize` can mislabel a corrupt typed row as `Legacy` |
| Communication-014 | [Communication](Communication/findings.md) | Untrusted gRPC `correlation_id` flows directly into an Akka actor name |
| Communication-015 | [Communication](Communication/findings.md) | No test exercises the real gRPC client factory across a node flip |
| ConfigurationDatabase-014 | [ConfigurationDatabase](ConfigurationDatabase/findings.md) | Redundant, inconsistent cast on one `HasConversion` call |
| DataConnectionLayer-017 | [DataConnectionLayer](DataConnectionLayer/findings.md) | `WriteBatchAsync` aborts the whole batch on a mid-batch disconnect |
| DeploymentManager-017 | [DeploymentManager](DeploymentManager/findings.md) | `GetDeploymentStatusAsync` XML doc describes behaviour it does not implement |
| ExternalSystemGateway-017 | [ExternalSystemGateway](ExternalSystemGateway/findings.md) | `BuildUrl` appends a bare trailing `?` when a GET method's parameters are all null |
| HealthMonitoring-013 | [HealthMonitoring](HealthMonitoring/findings.md) | Offline-check interval comment claims "shorter timeout" but only ever uses `OfflineTimeout` |
| HealthMonitoring-014 | [HealthMonitoring](HealthMonitoring/findings.md) | `HealthMonitoringOptions` intervals are unvalidated; a zero/negative value crashes the hosted service |
| HealthMonitoring-016 | [HealthMonitoring](HealthMonitoring/findings.md) | `SiteHealthCollector.CollectReport` reads `DateTimeOffset.UtcNow` directly instead of an injected `TimeProvider` |
| Host-013 | [Host](Host/findings.md) | `:F0` rounding of cluster timing values silently degrades sub-second configuration |
| Host-014 | [Host](Host/findings.md) | Serilog sinks are hard-coded in `Program.cs`, not configuration-driven (REQ-HOST-8) |
| Host-015 | [Host](Host/findings.md) | `StartupRetry` retries on every exception type, including permanent failures |
| InboundAPI-017 | [InboundAPI](InboundAPI/findings.md) | `RouteHelper` / `RouteTarget` has no test coverage |
| ManagementService-016 | [ManagementService](ManagementService/findings.md) | Unexpected exception messages returned verbatim to HTTP callers |
| ManagementService-017 | [ManagementService](ManagementService/findings.md) | QueryDeploymentsCommand has no test coverage |
| NotificationService-017 | [NotificationService](NotificationService/findings.md) | `NotificationOptions` is bound from configuration but never read (dead config) |
| NotificationService-018 | [NotificationService](NotificationService/findings.md) | Concurrency limiter: lock-free read of a non-volatile field, never resized on redeployment, never disposed |
| Security-013 | [Security](Security/findings.md) | `ExtractFirstRdnValue` mis-parses group DNs containing escaped commas |
| Security-015 | [Security](Security/findings.md) | Username is not trimmed before use in the LDAP filter, fallback DN, and JWT claims |