DTDE Development Plan - Implementation Phases¶

Phase 1: Foundation (4 weeks)
├── Core metadata models
├── Sharding strategies (property-agnostic)
├── Storage mode abstractions
└── Unit test infrastructure

Phase 2: EF Core Integration (4 weeks)
├── DbContext options extension
├── Fluent API extensions (ShardBy, WithStorageMode)
├── Table sharding implementation
└── Integration tests

Phase 3: Query Engine (5 weeks)
├── Shard query planner
├── Parallel query executor
├── Result merger
└── Performance benchmarks

Phase 4: Advanced Features (4 weeks)
├── Database sharding (multi-DB)
├── Manual table support (sqlproj)
├── Optional temporal module
└── Consistency handling

Phase 5: Production Readiness (3 weeks)
├── Documentation
├── Performance optimization
├── NuGet packaging
└── Sample applications

Total: ~20 weeks (5 months)

[ ] Create solution structure
    src/
    ├── Dtde.Core/
    ├── Dtde.EntityFramework/
    └── Dtde.Abstractions/
    tests/
    ├── Dtde.Core.Tests/
    └── Dtde.EntityFramework.Tests/

[ ] Configure Directory.Build.props
    - .NET 8.0 target
    - Nullable enabled
    - Implicit usings
    - Code analysis rules

[ ] Implement PropertyMetadata
    - PropertyName, PropertyType, ColumnName
    - Compiled getters/setters

[ ] Implement ShardingConfiguration
    - ShardKeyExpression (LambdaExpression)
    - StrategyType enum
    - StorageMode enum

[ ] Implement EntityMetadata
    - ClrType, TableName, SchemaName
    - PrimaryKey, Sharding (required)
    - TemporalConfig (optional)

[ ] Implement ShardMetadata
    - ShardId, Name
    - TableName or ConnectionString
    - ShardPredicate (LambdaExpression)

[ ] Implement IShardingStrategy
    - GetShardKey method
    - GetTargetShards method

[ ] Implement PropertyBasedStrategy
    - Simple property value matching
    - Equal/In operators

[ ] Implement DateRangeStrategy
    - Year/Quarter/Month intervals
    - Date range intersection

[ ] Implement HashStrategy
    - Consistent hashing
    - Configurable shard count

[ ] Implement IShardStorage
    - TableShardStorage (same DB)
    - GetShardContext method

[ ] Implement MetadataRegistry
    - Entity registration
    - Shard registration
    - Validation

[ ] Write unit tests (85% coverage)

[ ] Implement DtdeOptionsExtension
    - Implement IDbContextOptionsExtension
    - Register DTDE services
    - Configure service replacements

[ ] Implement DtdeOptionsBuilder
    - ConfigureEntity<T> method
    - SetMaxParallelShards method
    - EnableDiagnostics method

[ ] Implement Fluent API extensions
    - ShardBy<TEntity> extension
    - ShardByDate<TEntity> extension
    - ShardByHash<TEntity> extension
    - WithStorageMode extension

[ ] Implement DtdeDbContext
    - Shard context management
    - Dynamic model caching

[ ] Implement ShardQueryInterceptor
    - Detect shardable queries
    - Route to correct shard table(s)
    - Rewrite table names

[ ] Implement DtdeModelFinalizer
    - Read model annotations
    - Build EntityMetadata from model
    - Register with MetadataRegistry

[ ] Write integration tests (table sharding)
    - Single shard queries
    - Multi-shard queries
    - Insert routing

[ ] Implement DtdeQueryDefinition
    - Capture expression tree
    - Extracted shard key predicates
    - Ordering specifications

[ ] Implement ShardQueryPlanner
    - Resolve target shards from predicates
    - Build per-shard query expressions
    - Calculate per-shard take limits

[ ] Implement ParallelQueryExecutor
    - Create per-shard DbContext instances
    - Execute queries in parallel
    - Use SemaphoreSlim for bounded concurrency

[ ] Implement ResultMerger
    - Concatenate shard results
    - Apply global ordering
    - Apply global Skip/Take

[ ] Implement diagnostics
    - ShardResolvedEvent
    - QueryExecutedEvent
    - Per-shard timing

[ ] Create benchmark suite
    - Single shard queries
    - Multi-shard queries
    - Pagination queries
    - Large result set handling

[ ] Write multi-shard integration tests

[ ] Implement DatabaseShardStorage
    - Connection string per shard
    - DbContext factory per database
    - Connection pooling

[ ] Implement ManualShardStorage
    - Pre-defined table mappings
    - Predicate-based routing
    - MigrationsEnabled = false support

[ ] Implement temporal query extensions
    - ValidAt<TEntity> method
    - AllVersions<TEntity> method
    - ValidBetween<TEntity> method

[ ] Implement HasTemporalValidity Fluent API
    - Property-agnostic start/end
    - Open-ended validity support

[ ] Implement SaveChangesWithVersioningAsync
    - Explicit opt-in for versioning
    - Close old version + create new
    - Cross-shard version bump

[ ] Implement cross-shard write handling
    - Transaction coordination
    - Best-effort consistency
    - Diagnostic events

[ ] Write advanced integration tests

[ ] Complete API documentation
    - XML comments on all public types
    - Examples in remarks
    - Cross-references

[ ] Write README.md
    - Quick start guide
    - Configuration reference
    - FAQ

[ ] Write architecture documentation
    - Component diagrams
    - Flow diagrams
    - Decision records

[ ] Performance optimization
    - Expression caching
    - Connection pooling
    - Compiled delegates

[ ] Configure NuGet packaging
    - Package metadata
    - Symbol packages
    - Source link

[ ] Create sample application
    - Contract management API
    - Multi-shard setup
    - Docker compose