Persistency Documentation

This documentation describes the Persistency module of S-CORE. The module implements the Persistency feature with the Key-Value-Storage (KVS), which stores, retrieves and manages key-value pairs persistently in JSON format on the file system. It provides a Rust and a C++ implementation.

The documentation follows the SCORE module folder structure and the SCORE building blocks concept. The feature requirements are maintained in the SCORE platform repository.

Overview

This repository provides a standardized setup for projects using C++ or Rust and Bazel as a build system. It integrates best practices for build, test, CI/CD and documentation.

Feature Documentation

The Feature documentation covers the feature-level definition of the Persistency module, including architecture and safety planning artifacts.

• Persistency

Title	ID	Safety	Security	Status
Persistency Architecture Inspection Checklist	doc__persistency_arc_inspection	ASIL_B	YES	draft
Persistency DFA	doc__persistency_dfa	ASIL_B	NO	valid
Persistency FMEA	doc__persistency_fmea	ASIL_B	NO	valid
Persistency KVS Feature Architecture	doc__persistency_kvs_architecture	ASIL_B	NO	valid
Persistency KVS Security WPs	doc__persistency_security_wp	ASIL_B	YES	valid
Persistency Safety WPs	doc__persistency_safety_wp	ASIL_B	NO	valid
STRIDE	doc__persistency_stride	ASIL_B	YES	valid

Module Documentation

The Module documentation covers the module-level view (Persistency Module), including architecture, safety management documents, and the user manual.

• Verification Report

Title	ID	Safety	Security	Status
Persistency Codeowners	doc__persistency_codeowners	ASIL_B	YES	valid
Persistency Module Verification Report	doc__persistency_verification_report	ASIL_B	NO	valid
Persistency Release Note	doc__persistency_release_note	ASIL_B	NO	valid
Persistency Safety Analysis Checklist	doc__persistency_safety_analysis_fdr	ASIL_B	YES	valid
Persistency Safety Analysis Checklist	doc__module_safety_analysis_fdr	ASIL_B	YES	valid
Persistency Safety Manual	doc__persistency_safety_manual	ASIL_B	NO	valid
Persistency Safety Package Formal Review	doc__persistency_safety_package_fdr	ASIL_B	NO	valid
Persistency Safety Plan	doc__persistency_safety_plan	ASIL_B	NO	valid
Persistency Safety Plan Formal Review	doc__persistency_safety_plan_fdr	ASIL_B	NO	valid
Persistency Security Manual	doc__persistency_security_manual	ASIL_B	YES	draft
Persistency Security Package Formal Review	doc__persistency_sec_pkg_fdr	ASIL_B	YES	valid
Persistency Security Plan	doc__persistency_security_plan	ASIL_B	YES	valid
Persistency Security Plan Formal Review	doc__persistency_security_plan_fdr	ASIL_B	YES	valid

Component Documentation

The Components documentation provides detailed documentation for each individual library component, including requirements, architecture, and design decisions:

• Component documentation

Title	ID	Safety	Security	Status
KVS	doc__kvs	ASIL_B	NO	valid
KVS Architecture Inspection Checklist	doc__kvs_arc_inspection	ASIL_B	YES	draft
KVS Component Architecture	doc__kvs_component_architecture	ASIL_B	YES	valid
KVS Detailed Design	doc__kvs_detailed_design	ASIL_B	NO	draft
KVS DFA	doc__kvs_dfa	ASIL_B	NO	valid
KVS FMEA	doc__kvs_fmea	ASIL_B	NO	valid
KVS Implementation Inspection Checklist	doc__kvs_impl_inspection	ASIL_B	YES	draft
KVS Module Architecture	doc__kvs_architecture	ASIL_B	NO	valid
KVS Requirements	doc__kvs_requirements	ASIL_B	NO	valid
KVS Requirements Inspection Checklist	doc__kvs_req_inspection	ASIL_B	YES	valid

Examples

Usage examples of the Rust implementation are located in score/kvs/rust_kvs/examples:

• basic.rs: creating a KVS instance with KvsBuilder and basic key-value operations

• defaults.rs: usage of default values

• snapshots.rs: snapshot count and snapshot restore

• custom_types.rs: serialization and deserialization of custom types

• migration.rs: migration between storage backends

The example basic.rs is executed with cargo run -p rust_kvs --example basic, the other examples accordingly with their file name. The integration of the module into a Bazel project is described in examples/README.md.

Quick Start - Building and Testing

To build the module:

bazel build --config=per-x86_64-linux -- //score/...

Building without an explicit --config (e.g. per-x86_64-linux, per-x86_64-qnx, per-arm64-qnx) is not supported.

To run all tests:

bazel test //...

To run Unit Tests:

bazel test //:unit_tests

To run Component / Feature Integration Tests:

bazel test //:cit_tests

Module Build Configuration

The project_config.bzl file at the root of the module defines metadata used by Bazel macros. This file controls build behavior and project-specific settings. It should follow the S-CORE definition. See S-CORE user guide for project_config.bzl for details.

Example:

PROJECT_CONFIG = {
    "asil_level": "ASIL_B",
    "source_code": ["cpp", "rust"],
}

The configuration enables conditional build behavior:

• Language-specific tools: For C++ code, tools like clang-tidy are used; for Rust code, clippy is used

• Safety level: The ASIL level affects safety-related build settings and validation

• Source code languages: The build system optimizes for the configured languages