7.2 KiB
Feature Engineering Specification
Persistence & Data Management Features
Feature Group ID: FG-DATA
Scope: Sensor Hub (Sub-Hub only)
Target Platform: ESP32-S3–based Sensor Hub
Applies To: Indoor poultry farm sensor hubs
Dependencies:
-
Sensor Data Acquisition (FG-DAQ)
-
Data Quality & Calibration (FG-DQC)
-
Diagnostics & Health Monitoring (FG-DIAG)
-
System State Management / Teardown Mechanism
1. Purpose and Objectives
The Persistence & Data Management Features define how the Sensor Hub stores, protects, and manages critical runtime and historical data. These features ensure that:
-
Sensor data and system state are not lost during resets or failures
-
Data storage is abstracted from application logic
-
Critical data is safely handled during firmware updates, configuration changes, or fatal faults
The persistence layer is a foundational system service, supporting diagnostics, calibration, OTA, and recovery operations.
2. Feature Overview and Relationships
Feature ID | Feature Name | Primary Objective | Related Features |
|---|---|---|---|
F-DATA-01 | Persistent Sensor Data Storage | Store timestamped sensor data | DAQ, COM |
F-DATA-02 | Data Persistence Abstraction (DP) | Abstract storage access | Application Layer |
F-DATA-03 | Safe Data Handling During State Transitions | Protect data during teardown | OTA, System Mgmt |
3. Functional Feature Descriptions
3.1 F-DATA-01: Persistent Sensor Data Storage
Description
The system shall persist timestamped sensor data to non-volatile storage to support historical analysis, diagnostics correlation, and recovery scenarios.
Persistence may include:
-
Filtered sensor values
-
Timestamps
-
Sensor validity and status metadata
The persistence policy (frequency, retention window, overwrite behavior) is configurable and optimized for storage longevity and performance.
Key Capabilities
-
Non-volatile storage (SD card / NVM)
-
Timestamped records
-
Configurable retention policy
-
Integration with DAQ and COM
3.2 F-DATA-02: Data Persistence Abstraction (DP Component)
Description
The system shall provide a Data Persistence (DP) component that abstracts storage access for all upper layers. Application and feature modules interact with the DP component rather than directly accessing storage hardware.
The DP component manages:
-
Data model definitions
-
Serialization and deserialization
-
Storage backend selection
-
Consistency and integrity guarantees
Key Capabilities
-
Unified persistence API
-
Storage backend abstraction
-
Centralized data ownership
-
Reduced coupling between layers
3.3 F-DATA-03: Safe Data Handling During State Transitions
Description
The system shall ensure safe and deterministic handling of data during critical state transitions, including:
-
Firmware updates (OTA)
-
Machine Constants updates
-
System resets
-
Fatal error handling
Before entering such transitions, the system executes a controlled data finalization process to flush buffers, persist critical state, and verify data integrity.
Key Capabilities
-
Controlled data flush
-
Atomic write operations
-
Data integrity checks
-
Coordination with teardown mechanism
4. System Requirements (Formal SHALL Statements)
4.1 Persistent Sensor Data Storage
SR-DATA-001
The system shall persist timestamped sensor data in non-volatile storage.
SR-DATA-002
The system shall store sensor data together with sensor identifiers, timestamps, and validity status.
SR-DATA-003
The system shall support configurable data retention and overwrite policies.
4.2 Data Persistence Abstraction (DP Component)
SR-DATA-004
The system shall provide a Data Persistence (DP) component as the sole interface for persistent data access.
SR-DATA-005
The system shall prevent application and feature modules from directly accessing storage hardware.
SR-DATA-006
The DP component shall support serialization and deserialization of structured system data.
4.3 Safe Data Handling During State Transitions
SR-DATA-007
The system shall ensure that all critical runtime data is flushed to non-volatile storage before entering a controlled teardown or reset.
SR-DATA-008
The system shall protect data integrity during firmware updates and configuration changes.
SR-DATA-009
The system shall verify successful data persistence before completing a state transition.
5. Feature ↔ System Requirement Mapping
Feature ID | System Requirements |
|---|---|
F-DATA-01 | SR-DATA-001, SR-DATA-002, SR-DATA-003 |
F-DATA-02 | SR-DATA-004, SR-DATA-005, SR-DATA-006 |
F-DATA-03 | SR-DATA-007, SR-DATA-008, SR-DATA-009 |
6. Engineering Notes
-
The DP component aligns with your DP Stack already defined in the architecture.
-
Atomic write strategies (e.g., temp file + rename) are recommended.
-
Diagnostic events should be generated on persistence failures.
-
Storage wear-leveling considerations apply for SD/NVM.