DP44/enriched-qwen3-coder-next/Common/DTS.Common/Interface/TestSetups/CachedItemsList.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
Common/DTS.Common/Interface/TestSetups/CachedItemsList/ICachedItemsListView.cs Common/DTS.Common/Interface/TestSetups/CachedItemsList/ICachedItem.cs Common/DTS.Common/Interface/TestSetups/CachedItemsList/ICachedItemsListViewModel.cs	2026-04-16T03:12:02.925328+00:00	Qwen/Qwen3-Coder-Next-FP8	1	7a4cfa746af4994d

CachedItemsList

Purpose

This module defines the interface contracts for a cached items list feature within the test setup infrastructure. It establishes a standardized way to represent cached items (e.g., sensor or hardware configurations) along with metadata about their origin and validity, and provides a view-model layer to manage and expose the state of these cached items—including out-of-date or missing items—relative to current system data (sensors, calibrations, hardware). Its role is to decouple UI concerns (via ICachedItemsListView) from business logic (via ICachedItemsListViewModel) in a test setup context, enabling consistent handling of cached configuration data.

---

Public Interface

ICachedItemsListView

• Signature: interface ICachedItemsListView : IBaseView
• Behavior: A view interface (likely consumed by a UI layer) representing the presentation layer for the cached items list. Inherits from IBaseView, implying standard view lifecycle or binding behavior (not detailed here). No additional members defined.

ICachedItem

• Signature: interface ICachedItem
• Properties:
  • string Name { get; } – Human-readable identifier of the cached item.
  • string ObjectType { get; } – Type of the underlying object (e.g., "Sensor", "Hardware"), likely used for categorization or UI rendering.
  • DateTime CacheTime { get; } – Timestamp when the item was last cached (i.e., written to the cache).
  • DateTime DBTime { get; } – Timestamp of the item’s last modification in the database. DateTime.MinValue indicates the item no longer exists in the database; otherwise, it reflects the DB’s LastModified value.

ICachedItemsListViewModel

• Signature: interface ICachedItemsListViewModel : IBaseViewModel
• Properties:
  • ICachedItemsListView View { get; set; } – Reference to the associated view instance (for view-model-to-view binding).
  • ICachedItem[] CachedItems { get; set; } – Array of cached items currently managed by the view model.
• Methods:
  • bool SetCachedItems(ISensorData[] sensors, ISensorCalibration[] sensorCalibrations, IDASHardware[] hardware, IDASHardware[] allDAS) – Updates the cached items list by comparing/merging input data sources (current sensors, calibrations, and hardware). Returns true if the cached items list was modified as a result; false otherwise.
• Properties (read-only):
  • bool HasOutofDateCachedItems { get; } – true if any cached item’s DBTime is newer than its CacheTime, indicating the cache is stale for that item.
  • bool HasMissingSensors { get; } – true if any cached item references a sensor that no longer exists in the current sensors data (inferred from DBTime == DateTime.MinValue and ObjectType == "Sensor").

---

Invariants

• ICachedItem.DBTime == DateTime.MinValue iff the item is no longer present in the database.
• ICachedItem.CacheTime must be ≤ ICachedItem.DBTime for items still in the database (i.e., DBTime != DateTime.MinValue), as caching occurs after DB persistence.
• ICachedItemsListViewModel.CachedItems must be populated only via SetCachedItems(...), and its contents reflect the current state of the system’s sensors, calibrations, and hardware.
• HasOutofDateCachedItems is true iff at least one ICachedItem in CachedItems has DBTime > CacheTime.
• HasMissingSensors is true iff at least one ICachedItem in CachedItems has ObjectType == "Sensor" and DBTime == DateTime.MinValue.
• SetCachedItems(...) must process all provided arrays (sensors, sensorCalibrations, hardware, allDAS) to determine cache validity; partial processing is not permitted.

---

Dependencies

• Depends on:
  • DTS.Common.Base.IBaseView, DTS.Common.Base.IBaseViewModel (base interfaces for view/view-model).
  • DTS.Common.Interface.DataRecorders.ISensorData, ISensorCalibration (for sensor and calibration metadata).
  • DTS.Common.Interface.Sensors.IDASHardware (for DAS hardware metadata).
• Depended on by:
  • UI layers implementing ICachedItemsListView (e.g., WPF/WinForms views).
  • Higher-level view models or controllers that coordinate test setup workflows and need to validate cached configurations.
  • Likely consumed by a test setup wizard or configuration manager (not visible in source, but implied by naming).

---

Gotchas

• HasMissingSensors is not a general "missing items" flag—it specifically tracks sensors only (based on ObjectType == "Sensor"), per the DBTime == DateTime.MinValue convention. Missing hardware or calibration items are not covered by this property.
• SetCachedItems(...) accepts IDASHardware[] hardware and IDASHardware[] allDAS—the distinction between these two arrays is not clarified in the source (e.g., whether hardware is a subset of allDAS), making it unclear how overlap or precedence is handled.
• The return value of SetCachedItems(...) (true/false) indicates whether the CachedItems array changed, but does not indicate why (e.g., whether changes were due to staleness, missing items, or new items).
• No explicit thread-safety guarantees are defined; concurrent access to CachedItems or SetCachedItems(...) may require external synchronization.
• ObjectType values are not enumerated or validated—consumers must assume string literals (e.g., "Sensor", "Hardware") are used consistently elsewhere.