290f2be2fd
Three fixes from beta tester session feedback:
1. MCP error handling (backend/app/services/assistant_chat_service.py)
- The MCP Microsoft Learn integration was catching only BadRequestError.
Any other error type (APIStatusError, APIConnectionError, timeout) from
the external MCP server propagated as a 502, causing the generic error.
- Now catches all Exception types when MCP is active and retries without
MCP using the stable client.messages.create endpoint.
2. Frontend error UX (frontend/src/pages/AssistantChatPage.tsx)
- catch {} was silently swallowing all errors and inserting a generic
assistant message. Now: differentiates 429 (rate limit) vs 502/503
(AI unavailable), removes the optimistic user message on failure,
restores the failed message to the input so users can retry without
retyping, and logs errors to console for debugging.
3. Image attachments visible in chat (frontend/src/components/assistant/ChatMessage.tsx)
- Uploaded images were sent to the AI correctly but never shown in the
chat thread. Now captures preview URLs before clearing pendingUploads
and renders thumbnails above the user bubble, clickable to full size.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Troubleshooting Decision Tree - Backend API
FastAPI backend for the Troubleshooting Decision Tree application.
Quick Start
1. Set up Python environment
cd backend
python -m venv venv
# Windows
venv\Scripts\activate
# macOS/Linux
source venv/bin/activate
pip install -r requirements.txt
2. Start PostgreSQL database
Using Docker:
docker-compose up -d
Or install PostgreSQL locally and create a database:
CREATE DATABASE decision_tree;
3. Configure environment
Copy the example env file and update as needed:
cp .env.example .env
4. Run database migrations
alembic upgrade head
5. Start the server
uvicorn app.main:app --reload --host 0.0.0.0 --port 8000
The API will be available at:
- API: http://localhost:8000
- Docs: http://localhost:8000/api/docs
- ReDoc: http://localhost:8000/api/redoc
API Endpoints
Authentication
POST /api/v1/auth/register- Register new userPOST /api/v1/auth/login- Login (form data)POST /api/v1/auth/login/json- Login (JSON body)POST /api/v1/auth/refresh- Refresh tokenGET /api/v1/auth/me- Get current userPOST /api/v1/auth/logout- Logout
Trees
GET /api/v1/trees- List all treesGET /api/v1/trees/categories- List categoriesGET /api/v1/trees/search?q=query- Search treesGET /api/v1/trees/{id}- Get specific treePOST /api/v1/trees- Create tree (engineer/admin)PUT /api/v1/trees/{id}- Update tree (engineer/admin)DELETE /api/v1/trees/{id}- Delete tree (admin)
Sessions
GET /api/v1/sessions- List user's sessionsGET /api/v1/sessions/{id}- Get specific sessionPOST /api/v1/sessions- Start new sessionPUT /api/v1/sessions/{id}- Update sessionPOST /api/v1/sessions/{id}/complete- Complete sessionPOST /api/v1/sessions/{id}/export- Export session
Development
Create new migration
alembic revision --autogenerate -m "description"
Run migrations
alembic upgrade head
Rollback migration
alembic downgrade -1
Project Structure
backend/
├── alembic/ # Database migrations
│ └── versions/
├── app/
│ ├── api/
│ │ ├── endpoints/ # API route handlers
│ │ ├── deps.py # Dependencies (auth, etc.)
│ │ └── router.py # Main router
│ ├── core/
│ │ ├── config.py # Settings
│ │ ├── database.py # DB connection
│ │ └── security.py # JWT, password hashing
│ ├── models/ # SQLAlchemy models
│ ├── schemas/ # Pydantic schemas
│ └── main.py # FastAPI app
├── tests/
├── alembic.ini
├── docker-compose.yml
├── requirements.txt
└── README.md