Implement Postprocessor Multi-Database Bundle Support

[unclesp1d3r]

Implement Postprocessor Multi-Database Bundle Support

Overview

Add support for processing multi-database bundles in the postprocessor. Enable the generate, analyze, sql, and validate commands to handle both single-database and multi-database inputs.

Scope

What's Included:

• Extend load_schema() in file:dbsurveyor/src/main.rs to detect and handle multi-database bundles:
  • Detect MultiDatabaseResult vs DatabaseSchema in JSON
  • Parse MultiDatabaseOutput::Bundle variant
  • Parse MultiDatabaseOutput::PerDatabase variant (manifest + schemas)
• Add CLI flags for multi-database processing:
  • --combined: Generate single combined report for all databases
  • --split: Generate per-database reports in output directory
  • --database <NAME>: Process only specific database from bundle
• Update generate_documentation() to handle multi-database inputs:
  • Combined mode: Generate single Markdown with per-database sections
  • Split mode: Generate separate Markdown files per database
  • Single-database mode: Extract specific database from bundle
• Update analyze_schema() to handle multi-database inputs:
  • Show server-level statistics
  • Show per-database statistics
  • Show aggregate statistics (total tables across all databases)
• Update generate_sql() to handle multi-database inputs:
  • Combined mode: Generate single SQL file with per-database sections
  • Split mode: Generate separate SQL files per database
• Update validate_schema() to handle multi-database inputs:
  • Validate manifest structure
  • Validate each database schema
  • Report failures from MultiDatabaseResult.failures
  • Report object failures from each database
• Add unit tests for multi-database input detection and parsing
• Add integration tests for all commands with multi-database bundles

What's Explicitly Out:

• Cross-database analysis (foreign keys across databases, schema comparison) (deferred to post-v1.0)
• Visual diagrams (Mermaid ERD) for multi-database bundles (deferred)
• HTML reports for multi-database bundles (deferred)

Multi-Database Input Detection

flowchart TD
    Start[Load JSON file] --> Parse[Parse JSON]
    Parse --> CheckFormat{Contains<br/>'server_info'?}
    CheckFormat -->|Yes| MultiDB[Multi-database bundle]
    CheckFormat -->|No| SingleDB[Single database schema]
    
    MultiDB --> CheckVariant{Check variant}
    CheckVariant -->|Bundle| LoadBundle[Load MultiDatabaseResult]
    CheckVariant -->|PerDatabase| LoadManifest[Load manifest + schemas]
    
    SingleDB --> LoadSingle[Load DatabaseSchema]
    
    LoadBundle --> Process[Process based on CLI flags]
    LoadManifest --> Process
    LoadSingle --> Process

Loading

Acceptance Criteria

• load_schema() correctly detects and parses multi-database bundles
• --combined flag generates single report with all databases
• --split flag generates per-database reports in output directory
• --database <NAME> flag extracts and processes specific database
• generate command works with multi-database bundles (Markdown output)
• analyze command shows server-level and per-database statistics
• sql command generates DDL for multi-database bundles
• validate command validates multi-database bundles and reports failures
• Unit tests verify multi-database input detection and parsing
• Integration tests verify all commands with multi-database bundles
• Error messages clearly indicate when multi-database features are used

References

• Spec: spec:de2eeeb8-bfeb-4a11-98aa-84efc70568b2/820ca524-8c7d-4939-8097-f1158e7d67ea (Tech Plan - MultiDatabaseOutput)
• Core Flows: spec:de2eeeb8-bfeb-4a11-98aa-84efc70568b2/661dbe3d-b679-4287-991e-26f4a0dd98b9 (Flow 3 - batch documentation)
• Epic Brief: spec:de2eeeb8-bfeb-4a11-98aa-84efc70568b2/64fc1d47-e1e3-40db-a5dc-8dc9c248814c (v1.0 Must Have - postprocessor)
• Related Tickets:
  • ticket:de2eeeb8-bfeb-4a11-98aa-84efc70568b2/f609d694-2c7e-4e8d-9542-020dad45750b (MultiDatabaseOutput variants)