ngit-grasp/REVIEW_SUMMARY.md

ngit-grasp Architecture Review Summary

Investigation Complete ✅

After thorough investigation of:

1. The GRASP protocol specification
2. The reference implementation (ngit-relay in Go)
3. The git-http-backend Rust crate
4. The nostr-relay-builder Rust crate

Key Decision: Inline Authorization (Not Hooks)

Question: Should we use Git pre-receive hooks or inject logic directly into the HTTP handler?

Answer: Direct injection is both pragmatic and superior ✅

Why This Works

The git-http-backend Rust crate:

• Provides actix-web handlers for Git Smart HTTP protocol
• Spawns git-receive-pack as a subprocess
• We can intercept before spawning Git
• Full access to request body for parsing ref updates

Advantages

1. Better Error Handling: Direct HTTP responses vs. parsing hook stderr
2. Simpler Deployment: Single binary, no hook management
3. Easier Testing: Pure Rust unit tests, no shell scripts
4. Better Performance: Skip Git spawn for invalid pushes
5. Tighter Integration: Shared state between Git and Nostr

Architecture

Client Request
      ↓
actix-web Router
      ↓
git_receive_pack handler
      ↓
Parse ref updates from body
      ↓
Query local Nostr relay (in-process)
      ↓
Validate refs against state event
      ↓
   Valid? ──No──→ HTTP 403 Error
      ↓
     Yes
      ↓
Spawn git-receive-pack
      ↓
Stream to/from Git
      ↓
Return response to client

Documentation Created

1. README.md

• Project overview and goals
• Quick start guide
• Feature list and GRASP compliance
• Technology stack
• Comparison with reference implementation

2. docs/ARCHITECTURE.md

• Detailed architectural design
• Component breakdown with code examples
• Data flow diagrams
• Implementation details for:
  • Git protocol handling
  • Nostr relay configuration
  • Push validation logic
  • Repository management
• Performance considerations
• Testing strategy
• Future extensions (GRASP-02, GRASP-05)
• Deployment options

3. docs/DECISION_SUMMARY.md

• Investigation findings
• Hook vs. inline comparison
• Detailed rationale for inline approach
• Concerns and mitigations
• Next steps

4. docs/COMPARISON.md

• Side-by-side comparison with ngit-relay
• Component breakdown
• Performance estimates
• Code complexity analysis
• Migration path
• When to choose each implementation

5. docs/GIT_PROTOCOL.md

• Git Smart HTTP protocol reference
• Pkt-line format explanation
• Ref update parsing
• Validation logic examples
• Integration with actix-web
• Testing examples

6. .env.example

• Configuration template

Technology Stack

Core

• Rust 1.75+: Language
• actix-web 4: HTTP server
• tokio: Async runtime

Git

• git-http-backend 0.1.3: Git protocol handling
• tokio::process: Git subprocess management

Nostr

• nostr-relay-builder 0.43: Relay infrastructure
• nostr-sdk 0.43: Event handling and validation

Storage

• LMDB or NDB: Event storage (via nostr-relay-builder)
• File system: Git repositories

Project Structure

ngit-grasp/
├── src/
│   ├── main.rs              # Server setup
│   ├── config.rs            # Configuration
│   ├── git/
│   │   ├── mod.rs
│   │   ├── handler.rs       # Git HTTP handlers
│   │   └── authorization.rs # Push validation
│   ├── nostr/
│   │   ├── mod.rs
│   │   ├── relay.rs         # Relay setup
│   │   └── events.rs        # Event handlers
│   └── storage/
│       ├── mod.rs
│       └── repository.rs    # Repo management
├── docs/
│   ├── ARCHITECTURE.md      # Detailed design
│   ├── DECISION_SUMMARY.md  # Why inline auth
│   ├── COMPARISON.md        # vs ngit-relay
│   └── GIT_PROTOCOL.md      # Protocol reference
├── tests/
│   ├── integration/
│   └── fixtures/
├── README.md                # Overview
├── .env.example             # Config template
└── Cargo.toml               # Dependencies

Implementation Complexity

What We Need to Build

1. Git Protocol Parsing (~500 LOC)

   • Pkt-line parser
   • Ref update extraction
   • Request/response handling

2. Authorization Logic (~300 LOC)

   • Maintainer resolution (recursive)
   • State validation
   • PR ref handling

3. Nostr Relay Setup (~100 LOC)

   • Policies for announcements
   • Event hooks
   • NIP-11 configuration

4. Repository Management (~200 LOC)

   • Create/configure repos
   • Path management
   • Git command execution

5. Main Server (~200 LOC)

   • Route configuration
   • State management
   • Error handling

Total: ~1,300-1,500 LOC (similar to reference implementation)

What We Get from Libraries

• Nostr relay infrastructure (WebSocket, event store, etc.)
• Git protocol basics (upload-pack, receive-pack)
• Async runtime and HTTP server
• Nostr event parsing and validation

GRASP Compliance Roadmap

Phase 1: GRASP-01 Core (MVP)

• Basic HTTP server with routing
• Nostr relay with announcement policies
• Git upload-pack (clone/fetch)
• Git receive-pack with inline validation
• Repository provisioning on announcements
• Multi-maintainer support
• refs/nostr/* support for PRs
• CORS support
• NIP-11 relay info

Phase 2: GRASP-02 Proactive Sync

• Background event sync from listed relays
• Background Git sync from listed clones
• PR data fetching

Phase 3: GRASP-05 Archive

• Accept non-listed repositories
• Mirror/backup mode

Risks and Mitigations

Risk 1: Git Protocol Complexity

Impact: Medium
Likelihood: Low
Mitigation: Well-documented protocol, reference implementation exists, comprehensive testing

Risk 2: Performance of Inline Validation

Impact: Low
Likelihood: Low
Mitigation: State caching, async validation, benchmarking

Risk 3: nostr-relay-builder API Changes

Impact: Medium
Likelihood: Medium (it's in alpha)
Mitigation: Pin versions, monitor upstream, abstract relay interface

Risk 4: Compatibility with ngit Clients

Impact: High
Likelihood: Low
Mitigation: Follow GRASP spec exactly, test with ngit CLI

Success Criteria

1. Functional:

   • ✅ Accept repository announcements
   • ✅ Provision Git repositories
   • ✅ Validate pushes against state events
   • ✅ Serve clones/fetches
   • ✅ Support multi-maintainer repos
   • ✅ Handle PR refs

2. Performance:

   • ✅ < 50ms push validation overhead
   • ✅ < 100MB memory usage
   • ✅ Handle 100+ concurrent connections

3. Quality:

   • ✅ >80% test coverage
   • ✅ No clippy warnings
   • ✅ Comprehensive error handling
   • ✅ Good logging/observability

4. Compliance:

   • ✅ GRASP-01 compliant
   • ✅ NIP-34 compliant
   • ✅ NIP-11 compliant
   • ✅ Works with ngit CLI

Next Steps

Immediate (Week 1)

1. Set up Cargo workspace
2. Define core types (RefUpdate, RepositoryState, etc.)
3. Implement pkt-line parser
4. Write parser tests

Short-term (Week 2-3)

1. Implement Nostr relay with policies
2. Implement Git upload-pack handler
3. Implement Git receive-pack with validation
4. Repository management

Medium-term (Week 4-6)

1. Integration testing
2. GRASP-01 compliance testing
3. Documentation
4. Performance optimization

Long-term (Month 2+)

1. GRASP-02 implementation
2. Production hardening
3. Deployment tooling
4. Community feedback

Questions for Review

1. Architecture: Does the inline authorization approach make sense?
2. Complexity: Is the estimated LOC reasonable?
3. Dependencies: Are the chosen libraries appropriate?
4. Scope: Should we start with GRASP-01 only, or include GRASP-02?
5. Testing: What level of testing is needed before first release?
6. Deployment: Single binary, Docker, or both?

Recommendation

Proceed with implementation using the inline authorization architecture.

The design is:

• ✅ Technically sound
• ✅ Pragmatic and achievable
• ✅ Superior to hook-based approach
• ✅ Well-documented
• ✅ Testable
• ✅ GRASP-compliant

The Rust ecosystem provides excellent libraries for both Git and Nostr, making this implementation both feasible and maintainable.

References

• GRASP Protocol
• ngit-relay (Reference)
• NIP-34: Git Stuff
• git-http-backend crate
• nostr-relay-builder crate