# .NET 10 Upgrade Documentation Plan

## Overview
This document outlines the comprehensive plan for upgrading the Managing Apps solution from .NET 8 to .NET 10. The upgrade involves multiple .NET projects, Orleans clustering, and requires careful planning to minimize risks and ensure performance improvements.

## Current State Assessment

### Project Structure
- **Backend**: Multiple .NET projects targeting `net8.0`
  - Managing.Api (ASP.NET Core Web API)
  - Managing.Application (Business logic)
  - Managing.Domain (Domain models)
  - Managing.Infrastructure.* (Database, Exchanges, Storage, etc.)
  - Orleans 9.2.1 clustering with PostgreSQL persistence

- **Frontend**: React/TypeScript application (not affected by .NET upgrade)

### Key Dependencies
- Orleans 9.2.1 → Potential upgrade to Orleans 10.x
- Entity Framework Core 8.0.11 → 10.x
- ASP.NET Core 8.0.x → 10.x
- PostgreSQL/Npgsql 8.0.10 → Latest compatible version
- InfluxDB client and other infrastructure dependencies

## Upgrade Strategy

### Phase 1: Preparation (Week 1-2)

#### 1.1 Development Environment Setup
- [ ] Install .NET 10 SDK on all development machines
- [ ] Update CI/CD pipelines to support .NET 10
- [ ] Create dedicated upgrade branch (`feature/net10-upgrade`)
- [ ] Set up parallel environments (keep .NET 8 for rollback)

#### 1.2 Dependency Analysis
- [ ] Audit all NuGet packages for .NET 10 compatibility
- [ ] Identify packages requiring updates
- [ ] Test critical third-party packages in isolation
- [ ] Document breaking changes in dependencies

#### 1.3 Documentation Updates
- [ ] Update Dockerfiles (`FROM mcr.microsoft.com/dotnet/sdk:8.0` → `10.0`)
- [ ] Update deployment scripts
- [ ] Update README and architecture docs
- [ ] Create rollback procedures

### Phase 2: Core Framework Upgrade (Week 3-4)

#### 2.1 Project File Updates
**Priority Order:**
1. Managing.Common, Managing.Core (lowest risk)
2. Managing.Domain (pure domain logic)
3. Managing.Infrastructure.* (infrastructure concerns)
4. Managing.Application (business logic)
5. Managing.Api (entry point, highest risk)

**For each project:**
```xml
<!-- Before -->
<TargetFramework>net8.0</TargetFramework>

<!-- After -->
<TargetFramework>net10.0</TargetFramework>
<LangVersion>latest</LangVersion>
```

#### 2.2 Package Updates
**Microsoft Packages (Safe to update first):**
- Microsoft.AspNetCore.* → 10.x
- Microsoft.EntityFrameworkCore → 10.x
- Microsoft.Extensions.* → 10.x

**Third-party Packages:**
- Orleans → 10.x (if available) or stay on 9.x with compatibility testing
- Npgsql → Latest .NET 10 compatible
- All other packages → Update to latest versions

### Phase 3: Orleans Clustering Upgrade (Week 5-6)

#### 3.1 Orleans Assessment
- [ ] Evaluate Orleans 10.x preview vs staying on 9.x
- [ ] Test clustering configuration changes
- [ ] Validate grain persistence compatibility
- [ ] Performance test grain activation/deactivation

#### 3.2 Configuration Updates
```csharp
// Potential Orleans 10.x configuration changes
builder.Host.UseOrleans(siloBuilder =>
{
    // Updated clustering configuration syntax
    siloBuilder.ConfigureServices(services =>
    {
        // Add any new required services for Orleans 10.x
    });
});
```

#### 3.3 Clustering Validation
- [ ] Multi-server clustering test
- [ ] Grain state persistence test
- [ ] Reminders and timers validation
- [ ] Network partitioning simulation

### Phase 4: Database & Infrastructure (Week 7-8)

#### 4.1 Entity Framework Core
- [ ] Run EF Core migration scripts
- [ ] Test query performance with .NET 10
- [ ] Validate async operation improvements
- [ ] Memory usage optimization

#### 4.2 Database Providers
- [ ] PostgreSQL/Npgsql compatibility testing
- [ ] InfluxDB client validation
- [ ] Connection pooling optimization
- [ ] Transaction handling validation

### Phase 5: Performance Optimization (Week 9-10)

#### 5.1 Garbage Collection Tuning
```json
{
  "runtimeOptions": {
    "configProperties": {
      "System.GC.Concurrent": true,
      "System.GC.Server": true,
      "System.GC.HeapCount": 8,
      "System.GC.RetainVM": false,
      "System.GC.NoAffinitize": true
    }
  }
}
```

#### 5.2 Memory Management
- [ ] Implement `Span<T>` where appropriate
- [ ] Optimize string operations
- [ ] Use `ValueTask` for async operations
- [ ] Implement object pooling for hot paths

#### 5.3 Async/Await Optimization
- [ ] Use `ConfigureAwait(false)` appropriately
- [ ] Implement `IAsyncEnumerable` for streaming
- [ ] Optimize async state machines

## Risk Assessment

### High Risk Areas
1. **Orleans Clustering**: Most complex, potential for downtime
2. **Database Operations**: EF Core changes could affect queries
3. **Third-party Dependencies**: May not support .NET 10 immediately

### Medium Risk Areas
1. **ASP.NET Core Middleware**: Authentication, routing changes
2. **Serialization**: JSON/binary serialization changes
3. **Logging and Monitoring**: Integration compatibility

### Low Risk Areas
1. **Domain Models**: Pure C# logic, minimal changes
2. **Business Logic**: Framework-agnostic code

## Testing Strategy

### Unit Testing
- [ ] All existing tests pass on .NET 10
- [ ] New tests for .NET 10 specific features
- [ ] Performance regression tests

### Integration Testing
- [ ] API endpoint testing
- [ ] Database integration tests
- [ ] Orleans grain communication tests
- [ ] External service integration

### Performance Testing
- [ ] Memory usage benchmarks
- [ ] Request throughput testing
- [ ] Orleans grain activation latency
- [ ] Database query performance

### Staging Environment
- [ ] Full system testing in staging
- [ ] Load testing with production-like data
- [ ] Multi-day stability testing
- [ ] Failover and recovery testing

## Rollback Plan

### Immediate Rollback (First 24 hours)
- [ ] Keep .NET 8 containers available
- [ ] Feature flags for problematic features
- [ ] Database backup and restore procedures

### Gradual Rollback (1-7 days)
- [ ] Roll back individual services if needed
- [ ] Maintain API compatibility during rollback
- [ ] Client-side feature toggles

### Emergency Procedures
- [ ] Complete environment rollback to .NET 8
- [ ] Database state recovery
- [ ] User communication plan

## Success Metrics

### Performance Improvements
- [ ] 10-20% reduction in memory usage
- [ ] 5-15% improvement in request throughput
- [ ] Reduced GC pause times
- [ ] Faster application startup

### Reliability Improvements
- [ ] Zero downtime during upgrade
- [ ] No data loss or corruption
- [ ] All existing functionality preserved
- [ ] Improved error handling and logging

### Development Experience
- [ ] Faster build times
- [ ] Better debugging experience
- [ ] Access to latest .NET features
- [ ] Improved developer productivity

## Timeline and Milestones

### Week 1-2: Preparation
- [ ] Environment setup complete
- [ ] Dependency analysis finished
- [ ] Documentation updated

### Week 3-4: Core Upgrade
- [ ] All project files updated to .NET 10
- [ ] Microsoft packages updated
- [ ] Basic functionality testing passed

### Week 5-6: Orleans Upgrade
- [ ] Orleans configuration updated
- [ ] Clustering validation complete
- [ ] Grain functionality verified

### Week 7-8: Infrastructure
- [ ] Database operations validated
- [ ] External integrations tested
- [ ] Performance benchmarks established

### Week 9-10: Optimization
- [ ] Memory optimizations implemented
- [ ] Performance tuning complete
- [ ] Final testing and validation

### Week 11-12: Production Deployment
- [ ] Staging environment validation
- [ ] Production deployment
- [ ] Post-deployment monitoring
- [ ] Go-live decision

## Communication Plan

### Internal Stakeholders
- [ ] Weekly progress updates
- [ ] Risk assessments and mitigation plans
- [ ] Go/no-go decision checkpoints

### External Users
- [ ] Pre-upgrade notification
- [ ] Maintenance window communication
- [ ] Post-upgrade feature announcements

## Monitoring and Observability

### Key Metrics to Monitor
- Application memory usage
- CPU utilization
- Request latency and throughput
- Error rates and exceptions
- Orleans cluster health
- Database connection pools
- Garbage collection statistics

### Alerting Setup
- [ ] Memory usage thresholds
- [ ] Error rate monitoring
- [ ] Performance degradation alerts
- [ ] Orleans cluster health checks

## Contingency Plans

### Package Compatibility Issues
- [ ] Pin incompatible packages to working versions
- [ ] Implement adapter patterns for breaking changes
- [ ] Vendor critical dependencies if needed

### Performance Regression
- [ ] Performance profiling and optimization
- [ ] Feature flags for performance-intensive features
- [ ] Gradual rollout with A/B testing

### Orleans Issues
- [ ] Alternative clustering configurations
- [ ] Grain state migration procedures
- [ ] Fallback to single-server mode

## Resources Required

### Team
- 2-3 Senior .NET Developers
- 1 DevOps Engineer
- 1 QA Engineer
- 1 Product Owner

### Infrastructure
- Staging environment identical to production
- Performance testing environment
- Backup and recovery systems
- Monitoring and alerting setup

### Budget
- Development time: 8-12 weeks
- Infrastructure costs for testing environments
- Third-party tool licenses if needed
- Training and documentation time

---

## Appendices

### Appendix A: Package Compatibility Matrix
| Package | Current Version | .NET 10 Compatible | Notes |
|---------|-----------------|-------------------|-------|
| Microsoft.AspNetCore.* | 8.0.x | 10.x | Direct upgrade |
| Microsoft.EntityFrameworkCore | 8.0.11 | 10.x | Migration scripts required |
| Microsoft.Orleans.* | 9.2.1 | 10.x (preview) | Major version upgrade |

### Appendix B: Breaking Changes Checklist
- [ ] ASP.NET Core authentication middleware
- [ ] EF Core query behavior changes
- [ ] Orleans grain activation patterns
- [ ] Serialization format changes
- [ ] Logging framework updates

### Appendix C: Performance Benchmarks
**Baseline (.NET 8):**
- Memory usage: [TBD]
- Request throughput: [TBD]
- GC pause time: [TBD]

**Target (.NET 10):**
- Memory usage: [TBD] (10-20% reduction)
- Request throughput: [TBD] (5-15% improvement)
- GC pause time: [TBD] (significant reduction)

---

**Document Version:** 1.0
**Last Updated:** November 24, 2025
**Authors:** Development Team
**Reviewers:** Architecture Team, DevOps Team
