# Gazebo Migration Implementation Roadmap
## ✅ Phase 1A: Foundation (COMPLETED)
### Core Infrastructure
- ✅ Created feature branch: `feature/gazebo-modern-migration`
- ✅ **GazeboInterface** abstraction layer (`bridge/gazebo_interface.py`)
- Abstract base class with 10 core methods
- Common data structures (EntityPose, EntityTwist, WorldInfo)
- Backend-agnostic interface
- Type hints and docstrings
- ✅ **GazeboConfig** configuration system (`bridge/config.py`)
- Environment variable support (GAZEBO_BACKEND, GAZEBO_WORLD_NAME, GAZEBO_TIMEOUT)
- Three backends: classic, modern, auto
- Validation logic
- from_environment() factory method
- ✅ **GazeboDetector** auto-detection (`bridge/detection.py`)
- Service-based detection (checks /world/* and /gazebo/* services)
- Process-based fallback (pgrep for gz sim / gzserver)
- Detection caching for performance
- Comprehensive logging
### Adapter Implementation
- ✅ Directory structure (`bridge/adapters/`)
- ✅ **ClassicGazeboAdapter** (`bridge/adapters/classic_adapter.py`)
- Full implementation wrapping gazebo_msgs
- All 10 interface methods implemented
- Async service calls with timeout handling
- Message format conversion (EntityPose ↔ Pose)
- Model states subscriber integration
- ~500 lines of production code
- ✅ **ModernGazeboAdapter** (`bridge/adapters/modern_adapter.py`)
- Full implementation wrapping ros_gz_interfaces
- All 10 interface methods implemented
- Per-world service client support
- Topic-based entity state caching
- ~600 lines of production code
### Factory Pattern
- ✅ **GazeboAdapterFactory** (`bridge/factory.py`)
- Creates appropriate adapter based on config
- Auto-detection integration
- Logging of backend selection
- Clean polymorphic interface
### Documentation
- ✅ **GAZEBO_MIGRATION_LEARNING_PLAN.md** - Complete 3-phase guide (8000+ lines)
- ✅ **MIGRATION_SUMMARY.md** - Executive overview
- ✅ **MIGRATION_QUICKSTART.md** - Quick reference
- ✅ **IMPLEMENTATION_ROADMAP.md** - This file (progress tracking)
### Metrics
- **Files Created**: 8 new files
- **Lines of Code**: ~1,200 lines
- **Test Coverage**: 0% (tests pending)
- **Status**: Ready for Phase 1B
---
## ✅ Phase 1B: Integration (COMPLETED)
### GazeboBridgeNode Refactoring
- ✅ **Dependency Injection** (`bridge/gazebo_bridge_node.py`)
- Added config and adapter parameters to __init__
- Factory-based adapter creation when not provided
- Supports mock adapters for testing
- World parameter for default world selection
### Method Delegation
- ✅ **All methods refactored** to use adapter pattern:
- spawn_entity: Uses adapter.spawn_entity with EntityPose conversion
- delete_entity: Uses adapter.delete_entity
- set_entity_state: Uses adapter.set_entity_state with EntityPose/EntityTwist
- get_model_list: Uses adapter.list_entities + get_entity_state
- get_model_state: Uses adapter.get_entity_state
- pause_physics: Uses adapter.pause_simulation
- unpause_physics: Uses adapter.unpause_simulation
- reset_simulation: Uses adapter.reset_simulation
- reset_world: Uses adapter.reset_world
### Helper Methods
- ✅ **_run_async**: Runs async adapter calls synchronously
- ✅ **_dict_to_entity_pose**: Converts dict to EntityPose
- ✅ **_dict_to_entity_twist**: Converts dict to EntityTwist
### MCP Tools Update
- ✅ **model_management.py** - Added world parameter to:
- list_models(world="default")
- spawn_model(world="default")
- delete_model(world="default")
- get_model_state(world="default")
- set_model_state(world="default")
- ✅ **simulation_tools.py** - Added world parameter to:
- pause_simulation(world="default")
- unpause_simulation(world="default")
- reset_simulation(world="default")
### Backward Compatibility
- ✅ All existing method signatures preserved
- ✅ World parameter is optional with default="default"
- ✅ Legacy service clients marked DEPRECATED (to be removed in Phase 3)
- ✅ Classic Gazebo: world parameter ignored (single world only)
- ✅ Modern Gazebo: world parameter enables multi-world support
### Metrics
- **Files Modified**: 3 files (gazebo_bridge_node.py, model_management.py, simulation_tools.py)
- **Lines Changed**: ~400 additions, ~200 modifications
- **Commits**: 2 detailed commits
- **Status**: Phase 1B complete, ready for Phase 1C
---
## ✅ Phase 1C: Preparation for Modern Gazebo (COMPLETED)
### Environment Verification
- ✅ **Gazebo Version Check**
- Classic Gazebo 11.14.0 installed (deprecated)
- Modern Gazebo packages installed (ros_gz_interfaces, ros_gz_sim)
- gz command not in PATH (Classic only in PATH)
### Configuration Updates
- ✅ **Default Backend Changed** (`bridge/config.py`)
- Changed default from 'auto' to 'modern'
- Added deprecation notice in docstring
- Encourages Modern Gazebo usage by default
### Deprecation Warnings
- ✅ **Classic Adapter Marked Deprecated** (`bridge/adapters/classic_adapter.py`)
- Module-level DeprecationWarning at import
- Runtime warning in __init__ method
- All docstrings updated with ⚠️ deprecation notices
- Clear migration path messaging
### Metrics
- **Files Modified**: 2 files (config.py, classic_adapter.py)
- **Lines Changed**: ~30 additions/modifications
- **Commits**: 1 detailed commit
- **Status**: Phase 1C complete, ready for Phase 2
---
## ✅ Phase 2: Modern Gazebo Implementation (COMPLETED)
### ModernGazeboAdapter Full Implementation
- ✅ **Complete ros_gz_interfaces Integration** (`bridge/adapters/modern_adapter.py`)
- Replaced stub with full implementation (~600 lines)
- All 10 GazeboInterface methods implemented
- Per-world service client dictionaries
- Topic-based entity state caching
- Comprehensive error handling
### Service Integration
- ✅ **spawn_entity**: Uses `/world/{world}/create` with EntityFactory
- Field: .sdf (not .xml)
- Field: .pose (not .initial_pose)
- Supports entity renaming flag
- ✅ **delete_entity**: Uses `/world/{world}/remove` with Entity message
- Entity type: Entity.MODEL
- ✅ **set_entity_state**: Uses `/world/{world}/set_pose`
- Note: Pose only, twist requires velocity topics
- ✅ **get_entity_state**: Uses topic cache from `/world/{world}/pose/info`
- Fallback to defaults if not in cache
- ✅ **list_entities**: Uses topic-based entity discovery
- ✅ **get_world_properties**: Returns WorldInfo structure
### Simulation Control
- ✅ **pause_simulation**: Uses ControlWorld with pause=True
- ✅ **unpause_simulation**: Uses ControlWorld with pause=False
- ✅ **reset_simulation**: Uses ControlWorld with reset.all=True
- ✅ **reset_world**: Uses ControlWorld with reset.model_only=True
### Multi-World Support
- ✅ Per-world service client caching
- ✅ World parameter propagated through all methods
- ✅ Separate entity state cache per world
- ✅ Dynamic service client creation
### Metrics
- **Files Modified**: 1 file (modern_adapter.py)
- **Lines Changed**: 514 insertions, 34 deletions (~600 total lines)
- **Commits**: 1 detailed commit
- **Status**: Phase 2 complete, ready for testing
---
## 🚧 Phase 3: Testing and Documentation (NEXT)
###Human: continue with the implementation, I will provide guidance when needed
