# cacheable URL: /api/cache/cacheable/ Section: cache -------------------------------------------------------------------------------- cacheable - Bengal window.BENGAL_THEME_DEFAULTS = { appearance: 'dark', palette: 'snow-lynx' }; // Progressive Enhancement System Configuration window.Bengal = window.Bengal || {}; window.Bengal.enhanceBaseUrl = '/bengal/assets/js/enhancements'; window.Bengal.watchDom = true; window.Bengal.debug = false; (function () { try { var defaults = window.BENGAL_THEME_DEFAULTS || { appearance: 'system', palette: '' }; var defaultAppearance = defaults.appearance; if (defaultAppearance === 'system') { defaultAppearance = (window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches) ? 'dark' : 'light'; } var storedTheme = localStorage.getItem('bengal-theme'); var storedPalette = localStorage.getItem('bengal-palette'); var theme = storedTheme ? (storedTheme === 'system' ? defaultAppearance : storedTheme) : defaultAppearance; var palette = storedPalette ?? defaults.palette; document.documentElement.setAttribute('data-theme', theme); if (palette) { document.documentElement.setAttribute('data-palette', palette); } } catch (e) { document.documentElement.setAttribute('data-theme', 'light'); } })(); Skip to main content Magnifying Glass ESC Recent Clear Magnifying Glass No results for "" Try different keywords or check your spelling Start typing to search... ↑↓ Navigate ↵ Open ESC Close Powered by Lunr ᓚᘏᗢ Documentation Info About Arrow Clockwise Get Started Note Tutorials File Text Content Palette Theming Settings Building Starburst Extending Bookmark Reference Learning Tracks Releases Dev GitHub API Reference bengal CLI Magnifying Glass Search ⌘K Palette Appearance Chevron Down Mode Monitor System Sun Light Moon Dark Palette Snow Lynx Brown Bengal Silver Bengal Charcoal Bengal Blue Bengal List ᓚᘏᗢ Magnifying Glass Search X Close Documentation Info About Arrow Clockwise Get Started Note Tutorials File Text Content Palette Theming Settings Building Starburst Extending Bookmark Reference Learning Tracks Releases Dev GitHub API Reference bengal CLI Palette Appearance Chevron Down Mode Monitor System Sun Light Moon Dark Palette Snow Lynx Brown Bengal Silver Bengal Charcoal Bengal Blue Bengal API Reference __main__ bengal Caret Right Folder Analysis community_detection graph_analysis graph_reporting graph_visualizer knowledge_graph link_suggestions link_types page_rank path_analysis performance_advisor results Caret Right Folder Assets manifest pipeline Caret Right Folder Autodoc base config docstring_parser utils virtual_orchestrator Caret Right Folder Extractors cli openapi python Caret Right Folder Models cli common openapi python Caret Right Folder Cache asset_dependency_map cache_store cacheable compression dependency_tracker page_discovery_cache query_index query_index_registry taxonomy_index utils Caret Right Folder Build Cache autodoc_tracking core file_tracking fingerprint parsed_content_cache rendered_output_cache taxonomy_index_mixin validation_cache Caret Right Folder Indexes author_index category_index date_range_index section_index Caret Right Folder Cli __main__ base site_templates utils Caret Right Folder Commands assets build clean collections config debug explain fix health init perf project serve site skeleton sources theme utils validate Caret Right Folder Graph __main__ bridges communities orphans pagerank report suggest Caret Right Folder New config presets scaffolds site wizard Caret Right Folder Helpers cli_app_loader cli_output config_validation error_handling menu_config metadata progress site_loader traceback validation Caret Right Folder Skeleton hydrator schema Caret Right Folder Templates base registry Caret Right Folder Blog template Caret Right Folder Changelog template Caret Right Folder Default template Caret Right Folder Docs template Caret Right Folder Landing template Caret Right Folder Portfolio template Caret Right Folder Resume template Caret Right Folder Collections errors loader schemas validator Caret Right Folder Config defaults deprecation directory_loader env_overrides environment feature_mappings hash loader merge origin_tracker validators Caret Right Folder Content Layer entry loaders manager source Caret Right Folder Sources github local notion rest Caret Right Folder Content Types base registry strategies Caret Right Folder Core build_context cascade_engine menu section theme Caret Right Folder Asset asset_core css_transforms Caret Right Folder Page computed content metadata navigation operations page_core proxy relationships utils Caret Right Folder Site core data discovery factories page_caches properties section_registry theme Caret Right Folder Debug base config_inspector content_migrator delta_analyzer dependency_visualizer explainer incremental_debugger models reporter shortcode_sandbox Caret Right Folder Discovery asset_discovery content_discovery Caret Right Folder Fonts downloader generator Caret Right Folder Health autofix base health_check report Caret Right Folder Linkcheck async_checker ignore_policy internal_checker models orchestrator Caret Right Folder Validators anchors assets cache config connectivity cross_ref fonts links menu navigation output performance rendering rss sitemap taxonomy tracks Caret Right Folder Directives analysis checkers constants Caret Right Folder Orchestration asset content full_to_incremental incremental menu postprocess related_posts render section static streaming taxonomy Caret Right Folder Postprocess html_output redirects rss sitemap special_pages Caret Right Folder Output Formats index_generator json_generator llm_generator lunr_index_generator txt_generator utils Caret Right Folder Rendering api_doc_enhancer asset_extractor errors jinja_utils link_transformer link_validator pygments_cache renderer template_context template_profiler validator Caret Right 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reload_controller request_handler request_logger resource_manager utils Caret Right Folder Services validation Caret Right Folder Themes config Caret Right Folder Utils atomic_write autodoc build_context build_stats build_summary cli_output css_minifier dates dotdict error_handlers file_io file_lock hashing incremental_constants js_bundler live_progress logger metadata observability page_initializer pagination path_resolver paths performance_collector performance_report profile progress retry rich_console sections swizzle text theme_registry theme_resolution thread_local traceback_config traceback_renderer url_normalization url_strategy API Reference Cache ᗢ Caret Down Link Copy URL External Open LLM text Copy Copy LLM text Share with AI Ask Claude Ask ChatGPT Ask Gemini Ask Copilot Module cache.cacheable Cacheable Protocol - Type-safe cache contracts for Bengal. This module defines a Protocol that cacheable types can implement to ensure type-safe serialization and deserialization. Any type that needs to be cached to disk should implement this protocol. The protocol enforces: Consistent serialization pattern (to_cache_dict/from_cache_dict) Type-safe round-trip (obj == T.from_cache_dict(obj.to_cache_dict())) JSON-compatible serialization (str, int, float, bool, None, list, dict) Compile-time validation via mypy Design Philosophy: Unlike PageCore (which solves the live/cache/proxy split problem), the Cacheable protocol provides a lightweight contract for ANY type that needs caching, without requiring inheritance or base classes. Use Cacheable when: Type needs to be persisted to disk (cache files, indexes) Type should be serialized consistently across codebase Type-safety for serialization is desired No three-way split (live/cache/proxy) exists Use *Core base class (like PageCore) when: Type has three-way split (Live → Cache → Proxy) Templates access many properties (lazy loading matters) Manual sync between representations causes bugs See Also: bengal/cache/cache_store.py - Generic cache helper using this protocol bengal/core/page/page_core.py - PageCore (uses protocol) bengal/cache/taxonomy_index.py - TagEntry (uses protocol) architecture/cache.md - Cache architecture documentation plan/active/rfc-cacheable-protocol.md - Design rationale View source 1 Class Classes Cacheable Protocol for types that can be cached to disk. Types implementing this protocol can be automatical… 2 Caret Right Protocol for types that can be cached to disk. Types implementing this protocol can be automatically serialized to JSON and deserialized, with type checker validation. Contract Requirements: 1. JSON Primitives Only: to_cache_dict() must return only JSON-serializable types: str, int, float, bool, None, list, dict. 2. Type Conversion: Complex types must be converted: datetime → ISO-8601 string (via datetime.isoformat()) Path → str (via str(path)) set → sorted list (for stability) No Object References: Never serialize live objects (Page, Section, Asset). Use stable identifiers (usually string paths) instead. Round-trip Invariant: T.from_cache_dict(obj.to_cache_dict()) must reconstruct an equivalent object (== by fields). Stable Keys: Field names in to_cache_dict() are the contract. Adding/removing fields requires version bump in cache file. Runtime Validation: The @runtime_checkable decorator allows isinstance() checks: if isinstance(obj, Cacheable): data = obj.to_cache_dict() However, static type checking via mypy is the primary validation method. Example (Simple Type): @dataclass class TagEntry(Cacheable): tag_slug: str tag_name: str page_paths: list[str] updated_at: str def to_cache_dict(self) -> dict[str, Any]: return { 'tag_slug': self.tag_slug, 'tag_name': self.tag_name, 'page_paths': self.page_paths, 'updated_at': self.updated_at, } @classmethod def from_cache_dict(cls, data: dict[str, Any]) -> 'TagEntry': return cls( tag_slug=data['tag_slug'], tag_name=data['tag_name'], page_paths=data['page_paths'], updated_at=data['updated_at'], ) Example (Complex Type with datetime and Path): @dataclass class PageCore(Cacheable): source_path: str # Already stored as string title: str date: datetime | None tags: list[str] def to_cache_dict(self) -> dict[str, Any]: return { 'source_path': self.source_path, 'title': self.title, 'date': self.date.isoformat() if self.date else None, 'tags': self.tags, } @classmethod def from_cache_dict(cls, data: dict[str, Any]) -> 'PageCore': return cls( source_path=data['source_path'], title=data['title'], date=datetime.fromisoformat(data['date']) if data['date'] else None, tags=data['tags'], ) Example (Type with Object References): # WRONG: Don't serialize object references @dataclass class Page(Cacheable): section: Section # ❌ Object reference def to_cache_dict(self) -> dict[str, Any]: return {'section': self.section} # ❌ Not JSON-serializable! # CORRECT: Use stable identifier (path string) @dataclass class PageCore(Cacheable): section: str | None # ✅ Path string def to_cache_dict(self) -> dict[str, Any]: return {'section': self.section} # ✅ JSON-serializable Serialization Guidelines: datetime → ISO-8601 string: to_cache_dict: self.date.isoformat() if self.date else None from_cache_dict: datetime.fromisoformat(data['date']) if data['date'] else None Path → str: to_cache_dict: str(self.path) from_cache_dict: Path(data['path']) set → sorted list: to_cache_dict: sorted(list(self.tags)) from_cache_dict: set(data['tags']) Optional fields: to_cache_dict: self.optional_field # None is JSON-serializable from_cache_dict: data.get('optional_field') # Default to None Testing: Every Cacheable type should have a roundtrip test: def test_roundtrip(self): obj = MyType(field1="value", field2=42) data = obj.to_cache_dict() loaded = MyType.from_cache_dict(data) assert obj == loaded Performance: Protocol has zero runtime overhead (structural typing) isinstance() check is O(1) attribute lookup Serialization speed depends on implementation (~10µs for typical objects) Inherits from Protocol Methods 2 to_cache_dict Serialize to cache-friendly dictionary. Must return JSON-serializable types on… 0 dict[str, Any] Caret Right def to_cache_dict(self) -> dict[str, Any] Serialize to cache-friendly dictionary. Must return JSON-serializable types only: Primitives: str, int, float, bool, None Collections: list, dict (containing primitives) Complex types must be converted: datetime → ISO-8601 string (datetime.isoformat()) Path → string (str(path)) set → sorted list (for stability) No object references: Never serialize live objects (Page, Section). Use stable identifiers (paths as strings) instead. Returns dict[str, Any] — Dictionary suitable for JSON serialization from_cache_dict classmethod Deserialize from cache dictionary. Must be inverse of to_cache_dict(): ass… 1 T Caret Right def from_cache_dict(cls: type[T], data: dict[str, Any]) -> T Deserialize from cache dictionary. Must be inverse of to_cache_dict(): assert obj == cls.from_cache_dict(obj.to_cache_dict()) Handle type conversion: ISO-8601 string → datetime (datetime.fromisoformat()) string → Path (Path()) list → set (set()) Handle missing/optional fields: Use data.get('field', default_value) Preserve None for optional fields Parameters 1 data dict[str, Any] Dictionary from cache (JSON-deserialized) Returns T — Reconstructed instance ← Previous cache_store Next → compression List © 2025 Bengal ᓚᘏᗢ window.BENGAL_LAZY_ASSETS = { tabulator: '/bengal/assets/js/tabulator.min.js', dataTable: '/bengal/assets/js/data-table.js', mermaidToolbar: '/bengal/assets/js/mermaid-toolbar.9de5abba.js', mermaidTheme: '/bengal/assets/js/mermaid-theme.344822c5.js', graphMinimap: '/bengal/assets/js/graph-minimap.cc7e42e3.js', graphContextual: '/bengal/assets/js/graph-contextual.440e59c6.js' }; window.BENGAL_ICONS = { close: '/bengal/assets/icons/close.911d4fe1.svg', enlarge: '/bengal/assets/icons/enlarge.652035e5.svg', copy: '/bengal/assets/icons/copy.3d56e945.svg', 'download-svg': '/bengal/assets/icons/download.04f07e1b.svg', 'download-png': '/bengal/assets/icons/image.c34dfd40.svg', 'zoom-in': '/bengal/assets/icons/zoom-in.237b4a83.svg', 'zoom-out': '/bengal/assets/icons/zoom-out.38857c77.svg', reset: '/bengal/assets/icons/reset.d26dba29.svg' }; Arrow Up X -------------------------------------------------------------------------------- Metadata: - Author: lbliii - Word Count: 1696 - Reading Time: 8 minutes