Filesystem Observer: Atomic Metadata, Idempotency, and Logging Standards

Summary

Changes Made

• Filesystem Observer Spec
  • Defined and documented the Property Collector Pattern for atomic, non-destructive frontmatter updates.
  • Modularized observer services and templates for extensibility.
  • Required aggressive commenting and audit trails for every mutation.
  • Mandated idempotency: observer can process files repeatedly without redundant writes or infinite loops.
• Conditional Console Logging
  • Codified a config-driven pattern for all log statements.
  • All logs remain in code, toggled by user options.
  • Added optional helper for DRYness.
  • Standardized across all observer and pipeline code.
• Infinite Loop Prevention
  • Detected and repaired a feedback loop caused by malformed frontmatter.
  • Implemented logic to extract and repair only the first valid YAML block.
  • Adopted atomic property collector orchestration for all observer operations.
  • Ensured only changed key-value pairs are written, and only once per operation.

Impact

• Guarantees metadata consistency and auditability across all markdown content.
• Eliminates destructive or redundant file operations.
• Enables rapid debugging and safe extensibility for future features.
• Serves as a canonical reference for observer and pipeline architecture.

Documentation

• Filesystem Observer for Consistent Metadata in Markdown Files
• Issue Resolution: Conditional Console Logging
• Issue Resolution: Preventing Infinite Loops in Observers
• Prompt: Write-a-Code-Changelog-Entry.md

List of Affected Files

• tidyverse/observers/fileSystemObserver.ts
• tidyverse/observers/services/reportingService.ts
• tidyverse/observers/services/templateRegistry.ts
• tidyverse/observers/templates/
• tidyverse/observers/utils/
• tidyverse/observers/scripts/
• (and related markdown content in /content/specs/ and /content/lost-in-public/issue-resolution/)