platform-storage

Package: cloud_dog_storage
Standard: PS-85 (Storage Interfaces)
Status: Design complete, build-ready (v0.1.0)

Purpose

Drop-in Python library implementing the PS-85 Storage Interfaces standard. Provides a unified file/object storage abstraction with pluggable backends, consistent error handling, TLS configuration, path sanitisation, and observability.

Key Features

• 5 storage backends: Local filesystem, S3-compatible, WebDAV, FTP/FTPS, Google Drive
• Unified POSIX path model: Same /path/to/file addressing regardless of backend
• Config-driven backend selection: Switch from local to S3 via config change — zero code modification
• Sync + async: Sync primary API with AsyncStorageBackend wrapper for event-loop frameworks
• Security: Path traversal prevention, root boundary enforcement, credential redaction, TLS configuration
• Error taxonomy: Consistent StorageError hierarchy across all backends
• Factory pattern: build_storage_backend(config) creates the right backend from config
• Conformance suite: Reusable tests that validate any backend implementation
• Mock backend: In-memory MockStorageBackend for consumer project unit tests
• FastAPI integration: Optional Depends(get_storage_backend) helper
• Config delegation: Credentials pre-resolved by cloud_dog_config (PS-80) — no direct Vault/env reads in this package

Dependencies

• Required: pydantic
• Optional: requests (S3, WebDAV, Google Drive), cloud_dog_config, cloud_dog_logging, fastapi

Documents

• REQUIREMENTS.md — Functional and non-functional requirements (21 FRs)
• ARCHITECTURE.md — Module layout, component design, integration patterns
• TESTS.md — Test plan, directory structure, coverage map (72 tests: 32 UT + 10 ST + 20 IT + 5 AT + 5 QT)

Quick Start

from cloud_dog_storage import build_storage_backend
from cloud_dog_storage.config.models import StorageConfig

# Via cloud_dog_config (recommended — credentials pre-resolved from Vault)
from cloud_dog_config import get_config, bind_model
config = bind_model(get_config(), "storage", StorageConfig)
storage = build_storage_backend(config)

# Or direct construction (when cloud_dog_config not installed)
config = StorageConfig(backend="local", root_path="/data/files")
storage = build_storage_backend(config)

# Use (same API for all backends)
storage.write_bytes("/reports/q1.pdf", pdf_data)
data = storage.read_bytes("/reports/q1.pdf")
entries = storage.list_dir("/reports", recursive=True)
storage.delete_path("/reports/q1.pdf")

# Async usage
from cloud_dog_storage import AsyncStorageBackend
async_storage = AsyncStorageBackend(storage)
data = await async_storage.read_bytes("/reports/q1.pdf")

Reference Implementations

Existing code in these projects informed the package design:

Standards Alignment

Licence

Apache-2.0 — Copyright (c) 2026 Cloud-Dog, Viewdeck Engineering Limited