Feature/schema fingerprint

[Nechja]

This pull request introduces a schema fingerprinting feature to the schemalyzer tool, allowing users to quickly generate and compare SHA256 hashes of database schemas for instant change detection. The main changes include new commands, a robust fingerprinting implementation, integration into the CLI, and comprehensive tests to ensure reliability and correctness.

New Commands and CLI Integration:

• Added fingerprint and compare-fingerprints commands to the CLI, enabling users to generate a schema fingerprint and compare two fingerprints for quick schema change detection. [1] [2] [3]
• Updated README.md with detailed documentation and usage examples for the new commands, including flags and CI/CD integration patterns.

Fingerprinting Implementation:

• Implemented the Hasher in internal/fingerprint/hasher.go to normalize schema objects and generate a consistent SHA256 hash, ensuring order independence and ignoring comments for reliable comparisons.

  Functional Testing Results:

  • PostgreSQL fingerprint generation working
  • Deterministic hashing verified (same schema = same hash)
  • Different schemas produce different hashes
  • Compare-fingerprints correctly identifies matches/differences
  • Pre-computed hash comparison working
  • JSON and verbose output formats working
  • Tables-only flag produces different hashes

[Copilot]

Pull Request Overview

This PR introduces a schema fingerprinting feature to the schemalyzer tool, enabling users to generate SHA256 hashes of database schemas for instant change detection and quick comparison. The implementation provides deterministic, order-independent hashing while ignoring comments for reliable schema comparisons.

• Added fingerprint and compare-fingerprints CLI commands with comprehensive flag options
• Implemented robust schema normalization and hashing logic in the Hasher type
• Created comprehensive test coverage for fingerprint generation and comparison functionality

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
test/functional_test.sh	Functional test script validating fingerprint generation, deterministic hashing, and comparison features
internal/fingerprint/hasher_test.go	Unit tests covering fingerprint generation, determinism, order independence, and comment handling
internal/fingerprint/hasher.go	Core fingerprinting implementation with schema normalization and SHA256 hash generation
cmd/schemalyzer/commands/root.go	Integration of new fingerprint commands into the CLI
cmd/schemalyzer/commands/fingerprint.go	Implementation of the fingerprint command with various output options
cmd/schemalyzer/commands/compare_fingerprints.go	Implementation of the compare-fingerprints command for schema comparison
README.md	Documentation and usage examples for the new fingerprinting commands

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[Copilot]

Pull Request Overview

Copilot reviewed 9 out of 10 changed files in this pull request and generated 3 comments.

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}