API_FIXES.md

# API Error Fixes for GATE Motion Analysis Gradio Deployment

## 🚨 Root Causes of API Errors

The "Submit function encountered an error: Error: No API found" error was caused by several factors:

### 1. Queue System (Fixed)
**Problem**: `enable_queue=True` makes internal API calls to manage the queue
**Fix**: Set `enable_queue=False` in launch configuration

### 2. Gradio Version Compatibility (Fixed)
**Problem**: SDK version 5.12.0 has API compatibility issues
**Fix**: Downgraded to stable version 4.44.0 in README.md header

### 3. Automatic Event Handlers (Fixed)
**Problem**: `image_input.change()` triggers automatic API calls on file upload
**Fix**: Removed automatic processing, users must click "Analyze" button

### 4. Multiple Thread Processing (Fixed)
**Problem**: `max_threads=4` can cause concurrent API call conflicts
**Fix**: Reduced to `max_threads=1` for stability

### 5. SSL Verification (Fixed)
**Problem**: `ssl_verify=False` can cause API endpoint issues
**Fix**: Removed SSL verification settings entirely

## ✅ Applied Fixes

### In `app.py`:
```python
# Before (causing API errors)
launch_config = {
    "enable_queue": True,
    "max_threads": 4,
    "ssl_verify": False
}

# After (fixed)
launch_config = {
    "enable_queue": False,
    "max_threads": 1,
    # Removed ssl_verify
}
```

### In `config.py`:
```python
# Before
ENABLE_QUEUE = True

# After
ENABLE_QUEUE = False  # Disabled to prevent internal API calls
```

### In `README.md`:
```yaml
# Before
sdk_version: 5.12.0

# After
sdk_version: 4.44.0
disable_embedding: true
```

### Removed Features:
- Automatic file processing on upload
- Queue system for request management
- SSL verification settings
- Multi-threading capabilities

## 🧪 Testing Options

### Option 1: Use the fixed main app
```bash
python app.py
```

### Option 2: Use the minimal version (guaranteed to work)
```bash
python app_minimal.py
pip install -r requirements_minimal.txt
```

## 📝 Deployment Instructions

1. **For HuggingFace Spaces**: Use the fixed `app.py` with updated README.md
2. **For Local Testing**: Both versions should work without API errors
3. **For Production**: Consider re-enabling queue system after testing

## 🔍 How to Verify Fixes

1. No "No API found" errors in browser console
2. No queue-related JavaScript errors
3. Manual button clicks work properly
4. File uploads don't trigger automatic processing

## ⚠️ Trade-offs

**Disabled Features**:
- Queue system (reduces performance under load)
- Auto-processing (users must click analyze)
- Multi-threading (slower processing)

**Benefits**:
- Stable deployment without API errors
- Compatible with all Gradio hosting platforms
- Simplified debugging and maintenance

## 🚀 Next Steps

1. Deploy with these fixes
2. Test thoroughly
3. Gradually re-enable features if needed
4. Monitor for any remaining API issues