# Development Troubleshooting Guide

Common development issues and their solutions for the team.

---

## Table of Contents

- [Docker DNS/WiFi Issues (Digital Nomads)](#docker-dnswifi-issues-digital-nomads)
- [Go to Declaration Not Working (Ctrl+B)](#go-to-declaration-not-working-ctrlb)
- [Import Errors and Red Underlines](#import-errors-and-red-underlines)
- [Python Interpreter Issues](#python-interpreter-issues)
- [Debugging Not Working](#debugging-not-working)
- [Performance Issues](#performance-issues)
- [Git Integration Issues](#git-integration-issues)
- [Database Tool Issues](#database-tool-issues)
- [Frontend Asset Loading Issues](#frontend-asset-loading-issues)

---

## Docker DNS/WiFi Issues (Digital Nomads)

### Problem

When using Docker on Linux (Ubuntu/Xubuntu), the `docker0` bridge network interface can interfere with DNS resolution, causing:

- Hotel/public WiFi captive portals not loading
- DNS lookups failing or timing out
- Internet connectivity issues when Docker is running
- WiFi works fine until Docker starts

This happens because Docker's bridge network (`docker0`) can take priority over your WiFi connection for DNS resolution.

### Solution: Lower docker0 Priority (Recommended)

This solution lets Docker work normally while ensuring your WiFi DNS takes priority. Perfect for digital nomads working from hotels, cafes, and co-working spaces.

**Step 1: Create the NetworkManager dispatcher script**

```bash
sudo tee /etc/NetworkManager/dispatcher.d/99-docker-dns-fix << 'EOF'
#!/bin/bash
# Lower docker0 metric so WiFi takes priority for DNS
# This prevents Docker from interfering with hotel/public WiFi captive portals
if [ "$1" = "docker0" ]; then
    ip route del default via 172.17.0.1 dev docker0 2>/dev/null || true
fi
EOF
```

**Step 2: Make it executable**

```bash
sudo chmod +x /etc/NetworkManager/dispatcher.d/99-docker-dns-fix
```

**Step 3: Restart NetworkManager**

```bash
sudo systemctl restart NetworkManager
```

**Step 4: Verify it works**

```bash
# Start Docker
sudo systemctl start docker

# Check routes - docker0 should NOT have a default route
ip route | grep docker0
# Should return nothing or non-default routes only

# Your WiFi should still work
ping -c 3 google.com
```

### Alternative Solutions

#### Option A: Use Google DNS (Simple but less flexible)

If you don't need hotel captive portal DNS:

```bash
sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json << 'EOF'
{
  "dns": ["8.8.8.8", "8.8.4.4"],
  "dns-opts": ["ndots:1"]
}
EOF
sudo systemctl restart docker
```

!!! warning "Captive Portals"
    This option uses hardcoded Google DNS, which means hotel WiFi captive portals
    (login pages) may not work properly since they rely on DNS hijacking.

#### Option B: Stop Docker when not in use

```bash
# When you need WiFi without Docker interference
sudo systemctl stop docker
sudo ip link set docker0 down

# When you need Docker again
sudo systemctl start docker
```

### Installing Docker on Xubuntu/Ubuntu

If you haven't installed Docker yet:

```bash
# Update package index
sudo apt update

# Install prerequisites
sudo apt install -y ca-certificates curl gnupg

# Add Docker's official GPG key
sudo install -m 0755 -d /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
sudo chmod a+r /etc/apt/keyrings/docker.gpg

# Add the repository
echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

# Install Docker
sudo apt update
sudo apt install -y docker-ce docker-ce-cli containerd.io docker-compose-plugin

# Add your user to docker group (run docker without sudo)
sudo usermod -aG docker $USER

# Apply the DNS fix BEFORE using Docker
sudo tee /etc/NetworkManager/dispatcher.d/99-docker-dns-fix << 'EOF'
#!/bin/bash
if [ "$1" = "docker0" ]; then
    ip route del default via 172.17.0.1 dev docker0 2>/dev/null || true
fi
EOF
sudo chmod +x /etc/NetworkManager/dispatcher.d/99-docker-dns-fix

# Log out and back in for docker group, then verify
docker run hello-world
```

### Using Docker with this Project

After installing Docker with the DNS fix:

```bash
# Start PostgreSQL for development
make docker-up

# Run tests (auto-starts test database)
make test

# Stop when done
make docker-down
```

---

## Go to Declaration Not Working (Ctrl+B)

### Problem

When you press **Ctrl+B** (or Cmd+B on Mac) on a function, class, or variable, PyCharm shows:
- "Cannot find declaration to go to"
- No navigation occurs
- Imports are marked as unresolved even though code runs fine

**Example:**
```python
from app.services.admin_audit_service import admin_audit_service

# Ctrl+B on get_audit_logs doesn't work
logs = admin_audit_service.get_audit_logs(db, filters)
```

### Solution 1: Configure Source Roots (Most Common Fix)

PyCharm needs to know your project structure:

1. **Mark project root as Sources Root:**
   - Right-click on project root folder (`letzshop-product-import`)
   - Select **"Mark Directory as"** → **"Sources Root"**
   - The folder icon should turn blue

2. **Via Project Structure settings:**
   - **File** → **Settings** (Ctrl+Alt+S)
   - Navigate to **Project: letzshop-product-import** → **Project Structure**
   - Select your project root directory
   - Click the **"Sources"** button at the top
   - Click **Apply** → **OK**

3. **Verify the change:**
   - Your project root should now have a blue folder icon
   - The `.idea` folder should show the source root is configured

### Solution 2: Verify Python Interpreter

Ensure PyCharm is using the correct virtual environment:

1. **Check current interpreter:**
   - **File** → **Settings** → **Project** → **Python Interpreter**
   - Should show: `/home/samir/PycharmProjects/letzshop-product-import/.venv/bin/python`

2. **If wrong interpreter:**
   - Click the gear icon → **Add**
   - Select **"Existing environment"**
   - Navigate to: `[PROJECT_ROOT]/.venv/bin/python`
   - Click **OK**

3. **Wait for indexing:**
   - Bottom right corner will show "Indexing..."
   - Wait for it to complete before testing

### Solution 3: Invalidate Caches

PyCharm's index might be corrupted:

1. **File** → **Invalidate Caches...**
2. Select all checkboxes:
   - ✅ Invalidate and Restart
   - ✅ Clear file system cache and Local History
   - ✅ Clear downloaded shared indexes
3. Click **"Invalidate and Restart"**
4. **Wait 2-5 minutes** for re-indexing after restart

### Solution 4: Reimport Project

If nothing else works, rebuild the project structure:

1. **Close PyCharm**
2. **Delete PyCharm's cache folder:**
   ```bash
   rm -rf .idea/
   ```
3. **Reopen project in PyCharm:**
   - **File** → **Open**
   - Select project folder
   - Let PyCharm recreate `.idea/` folder
4. **Reconfigure:**
   - Set Python interpreter
   - Mark source roots
   - Wait for indexing

### Solution 5: Check .idea/workspace.xml

Sometimes workspace configuration gets corrupted:

```bash
# Close PyCharm first
rm .idea/workspace.xml
# Reopen PyCharm - it will regenerate this file
```

---

## Import Errors and Red Underlines

### Problem

Imports show red underlines and errors like:
- "Unresolved reference"
- "No module named 'app'"
- Code runs fine but PyCharm shows errors

### Solution

1. **Check Sources Root** (see above)

2. **Verify `__init__.py` files exist:**
   ```bash
   # All package directories need __init__.py
   ls -la app/__init__.py
   ls -la app/services/__init__.py
   ls -la app/api/__init__.py
   ```

3. **Add project root to PYTHONPATH:**
   - **File** → **Settings** → **Project** → **Project Structure**
   - Right-click project root → **"Mark as Sources Root"**

4. **Enable namespace packages** (if using PEP 420):
   - **File** → **Settings** → **Editor** → **Code Style** → **Python**
   - Check "Support namespace packages"

---

## Python Interpreter Issues

### Problem

- "No Python interpreter configured"
- Wrong Python version
- Missing packages even though they're installed

### Solution

1. **Verify virtual environment:**
   ```bash
   # In terminal
   which python  # Should show .venv/bin/python
   python --version  # Should show Python 3.13.x
   ```

2. **Configure in PyCharm:**
   - **File** → **Settings** → **Project** → **Python Interpreter**
   - Click gear icon → **Add**
   - Select **"Existing Environment"**
   - Choose: `[PROJECT_ROOT]/.venv/bin/python`

3. **Refresh interpreter packages:**
   - In Python Interpreter settings
   - Click refresh icon (⟳)
   - Wait for packages to reload

4. **Reinstall packages if needed:**
   ```bash
   source .venv/bin/activate
   pip install -r requirements.txt
   pip install -r requirements-dev.txt
   ```

---

## Debugging Not Working

### Problem

- Breakpoints are grayed out
- Debugger doesn't stop at breakpoints
- "Debugger is not attached"

### Solution 1: Check Run Configuration

1. **Edit configuration:**
   - Top right → Edit Configurations
   - Should use "Python" configuration type
   - Script path should point to your main file
   - Interpreter should be your virtual environment

2. **For FastAPI/Uvicorn:**
   - Module: `uvicorn`
   - Parameters: `main:app --reload`
   - Working directory: Project root

### Solution 2: Enable Gevent/Asyncio Support

For async code (FastAPI):

1. **File** → **Settings** → **Build, Execution, Deployment** → **Python Debugger**
2. Check **"Gevent compatible"** or **"Asyncio compatible"**
3. Restart debugger

### Solution 3: Check Breakpoint Settings

Right-click on breakpoint (red dot):
- Ensure "Enabled" is checked
- Check "Suspend" is set to "All"
- Remove any conditions if not needed

---

## Performance Issues

### Problem

- PyCharm is slow or freezing
- High CPU/memory usage
- Indexing takes forever

### Solution 1: Exclude Unnecessary Directories

Exclude directories PyCharm doesn't need to index:

1. **File** → **Settings** → **Project** → **Project Structure**
2. **Mark as "Excluded":**
   - `.venv` (if not already)
   - `node_modules`
   - `.pytest_cache`
   - `__pycache__`
   - `htmlcov`
   - `site` (mkdocs build output)

3. **Right-click these folders in Project view:**
   - **Mark Directory as** → **Excluded**

### Solution 2: Increase Memory

1. **Help** → **Change Memory Settings**
2. Increase heap size to **2048 MB** or higher
3. Restart PyCharm

### Solution 3: Disable Unused Plugins

1. **File** → **Settings** → **Plugins**
2. Disable plugins you don't use
3. Keep essential: Python, Git, Database, Markdown
4. Restart PyCharm

### Solution 4: Pause Indexing

If you need to work immediately:

1. **File** → **Pause Indexing**
2. Do your work
3. **Resume Indexing** when convenient

---

## Git Integration Issues

### Problem

- Git operations fail
- "Cannot run git" errors
- Changes not detected

### Solution 1: Configure Git Executable

1. **File** → **Settings** → **Version Control** → **Git**
2. **Path to Git executable:**
   - Linux/Mac: `/usr/bin/git`
   - Windows: `C:\Program Files\Git\bin\git.exe`
3. Click **"Test"** to verify
4. Click **OK**

### Solution 2: Check Git Root

1. **File** → **Settings** → **Version Control**
2. Verify your project root is listed
3. If missing, click **+** and add it

### Solution 3: Refresh VCS

1. **VCS** → **Refresh File Status**
2. Or: **Git** → **Refresh**
3. Or press: **Ctrl+F5**

---

## Database Tool Issues

### Problem

- Can't connect to PostgreSQL database
- "Connection refused" errors
- Tables not showing

### Solution 1: Verify Database Connection

1. **Database** tool window (usually right side)
2. Click **+** → **Data Source** → **PostgreSQL**
3. **Configure:**
   ```
   Host: localhost
   Port: 5432
   Database: orion_db
   User: [from .env file]
   Password: [from .env file]
   ```
4. Click **"Test Connection"**
5. Download drivers if prompted

### Solution 2: Check Database is Running

```bash
# Check if PostgreSQL is running
sudo systemctl status postgresql

# Start if not running
sudo systemctl start postgresql
```

### Solution 3: Verify .env Configuration

```bash
# Check your .env file
cat .env | grep DATABASE

# Should show something like:
DATABASE_URL=postgresql://user:password@localhost:5432/letzshop_db
```

---

## Frontend Asset Loading Issues

### Problem

- Tailwind CSS styles not loading
- Alpine.js not initializing
- Frontend pages look unstyled
- Console errors about missing CSS/JS files
- App doesn't work offline

### Solution 1: Verify CDN Fallback Files Exist

All frontends use CDN with local fallback. Check that local copies exist:

```bash
# From project root
ls -lh static/shared/css/tailwind.min.css
ls -lh static/shared/js/lib/alpine.min.js
```

**Expected output:**
```
-rw-r--r-- 1 user user 2.9M static/shared/css/tailwind.min.css
-rw-r--r-- 1 user user  44K static/shared/js/lib/alpine.min.js
```

**If files are missing:**
```bash
# Download Tailwind CSS
cd static/shared/css
curl -o tailwind.min.css https://cdn.jsdelivr.net/npm/tailwindcss@2.2.19/dist/tailwind.min.css

# Download Alpine.js
cd ../js/store
curl -o alpine.min.js https://cdn.jsdelivr.net/npm/alpinejs@3.13.3/dist/cdn.min.js
```

### Solution 2: Check Browser Console

Open DevTools (F12) and check the Console tab for errors:

**Common errors:**
- `GET http://localhost:8000/static/shared/css/tailwind.min.css [404 Not Found]` → File missing
- `Alpine.js CDN failed, loading local copy...` → Normal fallback behavior
- `Uncaught ReferenceError: Alpine is not defined` → Alpine.js failed to load

### Solution 3: Test CDN Fallback Behavior

To verify fallback works correctly:

1. **Start application:**
   ```bash
   uvicorn app.main:app --reload
   ```

2. **Test with CDN blocked:**
   - Open browser DevTools (F12)
   - Go to Network tab
   - Add request blocking rule for `cdn.jsdelivr.net`
   - Reload page

3. **Verify fallback:**
   - Check Console for: `⚠️ Alpine.js CDN failed, loading local copy...`
   - Check Network tab shows local files loaded
   - Page should still work normally

### Solution 4: Verify Static Files Mounting

Check that FastAPI is serving static files correctly:

**In `app/main.py`:**
```python
from fastapi.staticfiles import StaticFiles

app.mount("/static", StaticFiles(directory="static"), name="static")
```

**Test static file serving:**
```bash
# With app running, test directly:
curl http://localhost:8000/static/shared/css/tailwind.min.css | head -n 5
curl http://localhost:8000/static/shared/js/lib/alpine.min.js | head -n 5
```

### Solution 5: File Permissions

If files exist but return 403 Forbidden:

```bash
# Fix permissions
chmod 644 static/shared/css/tailwind.min.css
chmod 644 static/shared/js/lib/alpine.min.js
chmod 755 static/shared/css
chmod 755 static/shared/js/store
```

### Solution 6: For Offline Development

If working completely offline, the CDN will always fail. Verify:

1. **Console shows fallback message** (expected behavior)
2. **Local files load successfully**
3. **Page functions normally**

**To suppress CDN warnings when offline:**
- Accept that CDN will fail (expected)
- Fallback mechanism handles it automatically
- Or modify templates to use local-only (see [CDN Fallback Strategy](../frontend/cdn-fallback-strategy.md#optimization-strategies))

### Solution 7: Network Issues

If both CDN and local files fail intermittently:

1. **Check browser cache:**
   - Open DevTools → Network tab
   - Check "Disable cache" option
   - Hard reload: Ctrl+Shift+R

2. **Clear browser cache completely:**
   - Browser Settings → Privacy → Clear browsing data
   - Select "Cached images and files"
   - Clear data

3. **Check for firewall/proxy issues:**
   ```bash
   # Test CDN accessibility
   curl https://cdn.jsdelivr.net/npm/tailwindcss@2.2.19/dist/tailwind.min.css | head -n 5
   ```

### Related Documentation

See [CDN Fallback Strategy](../frontend/cdn-fallback-strategy.md) for complete details on:
- How the fallback mechanism works
- Updating local asset files
- Production deployment considerations
- Air-gapped deployment setup

---

## Quick Checklist for New Developers

When setting up PyCharm for the first time:

- [ ] Clone repository
- [ ] Create virtual environment: `python -m venv .venv`
- [ ] Activate: `source .venv/bin/activate`
- [ ] Install dependencies: `pip install -r requirements.txt`
- [ ] Open project in PyCharm
- [ ] Configure Python interpreter (`.venv/bin/python`)
- [ ] Mark project root as Sources Root
- [ ] Exclude `.venv`, `.pytest_cache`, `__pycache__` directories
- [ ] Configure Git executable
- [ ] Configure database connection
- [ ] Wait for indexing to complete
- [ ] Test: Ctrl+B on an import should work

---

## Still Having Issues?

### Check PyCharm Logs

1. **Help** → **Show Log in Explorer/Finder**
2. Look for errors in `idea.log`
3. Search for "ERROR" or "Exception"

### Enable Debug Logging

1. **Help** → **Diagnostic Tools** → **Debug Log Settings**
2. Add: `#com.intellij.python`
3. Reproduce the issue
4. Check logs

### Report to Team

If the issue persists:

1. Screenshot the error
2. Share PyCharm version: **Help** → **About**
3. Share Python version: `python --version`
4. Share OS: `uname -a` (Linux/Mac) or `ver` (Windows)
5. Post in team chat with:
   - What you were trying to do
   - What error you got
   - What you've tried so far

---

## Related Documentation

- [PyCharm Make Configuration](pycharm-configuration-make.md) - Configure Make with virtual environment
- [Contributing Guide](contributing.md) - Development workflow
- [Database Migrations](migration/database-migrations.md) - Working with Alembic