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ChuckandClaude Opus 5.5 2601cb4cbb chore(deprecation): remove the 35 APIs deprecated for 3.8.0 (#708) 
* chore(deprecation): remove the 35 APIs deprecated for 3.8.0

The usage scan (docs/DEPRECATIONS_3.8.md, regenerated 2026-10-01 and
committed here) finds no call or override of any of them in the 46
monorepo plugins or the 8 third-party plugins plugins.json lists; the
only core callers were other deprecated methods removed alongside.

- CacheManager: 13 methods, plus the private helpers only
  has_data_changed used (_has_*_changed, _is_market_open).
- DisplayManager: 7 methods, plus WEATHER_COLORS and the private
  _draw_sun/_cloud/_rain/_snow/_storm helpers only the icon methods used.
- FontManager: 14 methods, plus size_tokens, _save_overrides and
  _clear_plugin_font_cache. font_overrides and _load_overrides stay:
  resolve_font() still applies config/font_overrides.json.
  performance_stats stays: get_font() keeps it and tests read it.
- PluginManager.get_enabled_plugins.

test_deprecation.py pins only the two 3.9.0 markers now; the scanner
tests run against a stand-in core instead of the real markers. The
memory-tier tests read stats through log_memory_cache_stats() and the
component, and the test of the removed _clear_plugin_font_cache goes.
Docs drop the removed methods' reference entries; the Deprecated APIs
table becomes "Removed in 3.8.0". CHANGELOG gains a Removed section.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(deprecation): drop the test harness's copies of the removed icon methods

VisualTestDisplayManager still drew weather icons that DisplayManager no
longer has, so a plugin's visual tests could pass on calls that raise
AttributeError on the real display. Its draw_sun/draw_cloud/draw_rain/
draw_snow/draw_weather_icon/draw_text_with_icons, WEATHER_COLORS and the
private helpers go, with the tests that exercised them. The CHANGELOG's
Deprecations entries no longer say nothing is removed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-01 10:45:28 -04:00

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# Advanced Plugin Development
Advanced patterns, examples, and best practices for developing LEDMatrix plugins.
> **Adaptive layout:** for plugins that should render legibly on any panel
> size (fonts that grow on big panels, layouts that degrade gracefully on
> small ones), use the adaptive layout system — `self.layout`, `draw_fit`,
> `draw_image`, `scoreboard_regions` — documented in
> [ADAPTIVE_LAYOUT.md](ADAPTIVE_LAYOUT.md).
## Table of Contents
- [Using Weather Icons](#using-weather-icons)
- [Implementing Scrolling with Deferred Updates](#implementing-scrolling-with-deferred-updates)
- [Cache Strategy Patterns](#cache-strategy-patterns)
- [Font Management](#font-management)
- [Error Handling Best Practices](#error-handling-best-practices)
- [Performance Optimization](#performance-optimization)
- [Testing Plugins with Mocks](#testing-plugins-with-mocks)
- [Inter-Plugin Communication](#inter-plugin-communication)
- [Live Priority Implementation](#live-priority-implementation)
- [Dynamic Duration Support](#dynamic-duration-support)
---
## Using Weather Icons
The Display Manager's icon methods — `draw_weather_icon()`, `draw_sun()`,
`draw_cloud()`, `draw_rain()`, `draw_snow()` and `draw_text_with_icons()` —
were removed in 3.8.0. Draw your own icons instead: render them
onto a PIL image and paste it onto `self.display_manager.image`, or ship
icon images with the plugin. The weather plugin's `WeatherIcons` class is an
example. See [Deprecated APIs](PLUGIN_API_REFERENCE.md#deprecated-apis).
---
## Implementing Scrolling with Deferred Updates
For plugins that scroll content (tickers, news feeds, etc.), use scrolling state management to coordinate with the display system.
### Basic Scrolling Implementation
Scroll with `ScrollHelper`, configured by `src.common.scroll_config`, and
render one frame per `display()` call. Don't pace the scroll with
`time.sleep()`: `update_display()` blocks on the panel's
vsync, which is what paces a scroll. Pass the `frame_hold` that
`scroll_config.configure()` returned to `set_scrolling_state()`, or the
scroll runs faster than the configured speed (see
`set_scrolling_state()` in [PLUGIN_API_REFERENCE.md](PLUGIN_API_REFERENCE.md)).
```python
from PIL import Image, ImageDraw
from src.common import scroll_config
from src.common.scroll_helper import ScrollHelper
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.scroll_helper = ScrollHelper(
self.display_manager.width, self.display_manager.height, self.logger)
self.scroll_settings = scroll_config.configure(
self.scroll_helper,
plugin_config=self.config,
global_config=self.global_config,
display_manager=self.display_manager,
plugin_logger=self.logger,
)
def _build_scroll_image(self, text):
font = self.display_manager.regular_font
width = self.display_manager.get_text_width(text, font)
img = Image.new("RGB", (width, self.display_manager.height))
ImageDraw.Draw(img).text((0, 0), text, font=font, fill=(255, 255, 255))
self.scroll_helper.set_scrolling_image(img)
def display(self, force_clear=False):
if force_clear or self.scroll_helper.cached_image is None:
self._build_scroll_image(
"This is a long scrolling message that needs to scroll across the display...")
# Mark as scrolling (calling it every frame is fine)
self.display_manager.set_scrolling_state(
True, frame_hold=self.scroll_settings.frame_hold)
self.scroll_helper.update_scroll_position()
self.display_manager.image = self.scroll_helper.get_visible_portion()
self.display_manager.update_display()
if self.scroll_helper.is_scroll_complete():
# Mark as not scrolling when done
self.display_manager.set_scrolling_state(False)
```
### Deferred Updates During Scrolling
Use `defer_update()` to queue non-critical updates until scrolling completes:
```python
def update(self):
# Critical update - do immediately
self.fetch_latest_data()
# Non-critical metadata update - defer until not scrolling
self.display_manager.defer_update(
lambda: self.update_cache_metadata(),
priority=1
)
# Low priority cleanup - defer
self.display_manager.defer_update(
lambda: self.cleanup_old_data(),
priority=2
)
```
### Checking Scroll State
Check if currently scrolling before performing expensive operations:
```python
def update(self):
# Only do expensive operations when not scrolling
if not self.display_manager.is_currently_scrolling():
self.perform_expensive_operation()
else:
# Defer until scrolling stops
self.display_manager.defer_update(
lambda: self.perform_expensive_operation(),
priority=0
)
```
---
## Cache Strategy Patterns
Use appropriate cache strategies for different data types to optimize performance and reduce API calls.
### Basic Caching Pattern
```python
def update(self):
cache_key = f"{self.plugin_id}_data"
# Try to get from cache first
cached = self.cache_manager.get(cache_key, max_age=3600)
if cached:
self.data = cached
self.logger.debug("Using cached data")
return
# Fetch from API if not cached
try:
self.data = self._fetch_from_api()
self.cache_manager.set(cache_key, self.data)
self.logger.info("Fetched and cached new data")
except Exception as e:
self.logger.error(f"Failed to fetch data: {e}")
# Use stale cache if available (re-fetch with large max_age to bypass expiration)
expired_cached = self.cache_manager.get(cache_key, max_age=31536000) # 1 year
if expired_cached:
self.data = expired_cached
self.logger.warning("Using stale cached data due to API error")
```
### Using Cache Strategies
For automatic TTL selection based on data type:
```python
def update(self):
cache_key = f"{self.plugin_id}_weather"
# Automatically uses appropriate cache duration for weather data
cached = self.cache_manager.get_cached_data_with_strategy(
cache_key,
data_type="weather"
)
if cached:
self.data = cached
return
# Fetch new data
self.data = self._fetch_from_api()
self.cache_manager.set(cache_key, self.data)
```
### Sport-Specific Caching
For sports plugins, use sport-specific cache strategies:
```python
def update(self):
sport_key = "nhl"
cache_key = f"{self.plugin_id}_{sport_key}_games"
# get_background_cached_data() was removed in 3.8.0 — use get()
cached = self.cache_manager.get(cache_key, max_age=60)
if cached:
self.games = cached
return
# Fetch new games
self.games = self._fetch_games(sport_key)
self.cache_manager.set(cache_key, self.games)
```
### Cache Invalidation
Clear cache when needed:
```python
def on_config_change(self, new_config):
# Clear cache when API key changes
if new_config.get('api_key') != self.config.get('api_key'):
self.cache_manager.clear_cache(f"{self.plugin_id}_data")
self.logger.info("Cleared cache due to API key change")
super().on_config_change(new_config)
```
---
## Font Management
The display manager's built-in fonts and text measurement. For fonts shipped with a plugin, see [FONT_MANAGER.md](FONT_MANAGER.md).
### Using Different Fonts
```python
def display(self, force_clear=False):
if force_clear:
self.display_manager.clear()
# Use regular font for title
self.display_manager.draw_text(
"Title",
x=10, y=5,
font=self.display_manager.regular_font,
color=(255, 255, 255)
)
# Use small font for details
self.display_manager.draw_text(
"Details",
x=10, y=20,
font=self.display_manager.small_font,
color=(200, 200, 200)
)
# Use calendar font for compact text
self.display_manager.draw_text(
"Compact",
x=10, y=30,
font=self.display_manager.calendar_font,
color=(150, 150, 150)
)
self.display_manager.update_display()
```
### Measuring Text
Calculate text dimensions for layout:
```python
def display(self, force_clear=False):
if force_clear:
self.display_manager.clear()
text = "Hello, World!"
font = self.display_manager.regular_font
# Get text dimensions
text_width = self.display_manager.get_text_width(text, font)
font_height = self.display_manager.get_font_height(font)
# Center text horizontally
x = (self.display_manager.width - text_width) // 2
# Center text vertically
y = (self.display_manager.height - font_height) // 2
self.display_manager.draw_text(text, x=x, y=y, font=font)
self.display_manager.update_display()
```
### Multi-line Text
Render multiple lines of text:
```python
def display(self, force_clear=False):
if force_clear:
self.display_manager.clear()
lines = [
"Line 1",
"Line 2",
"Line 3"
]
font = self.display_manager.small_font
font_height = self.display_manager.get_font_height(font)
y = 5
for line in lines:
# Center each line
text_width = self.display_manager.get_text_width(line, font)
x = (self.display_manager.width - text_width) // 2
self.display_manager.draw_text(line, x=x, y=y, font=font)
y += font_height + 2 # Add spacing between lines
self.display_manager.update_display()
```
---
## Error Handling Best Practices
Implement robust error handling to ensure plugins fail gracefully.
### API Error Handling
```python
def update(self):
cache_key = f"{self.plugin_id}_data"
try:
# Try to fetch from API
self.data = self._fetch_from_api()
self.cache_manager.set(cache_key, self.data)
self.logger.info("Successfully updated data")
except requests.exceptions.Timeout:
self.logger.warning("API request timed out, using cached data")
cached = self.cache_manager.get(cache_key, max_age=7200) # Use older cache
if cached:
self.data = cached
else:
self.data = None
except requests.exceptions.RequestException as e:
self.logger.error(f"API request failed: {e}")
# Try to use cached data
cached = self.cache_manager.get(cache_key, max_age=7200)
if cached:
self.data = cached
self.logger.info("Using cached data due to API error")
else:
self.data = None
except Exception as e:
self.logger.error(f"Unexpected error in update(): {e}", exc_info=True)
self.data = None
```
### Display Error Handling
```python
def display(self, force_clear=False):
try:
if force_clear:
self.display_manager.clear()
# Check if we have data
if not self.data:
self._display_no_data()
return
# Render main content
self._render_content()
self.display_manager.update_display()
except Exception as e:
self.logger.error(f"Error in display(): {e}", exc_info=True)
# Show error message to user
try:
self.display_manager.clear()
self.display_manager.draw_text(
"Error",
x=10, y=16,
color=(255, 0, 0)
)
self.display_manager.update_display()
except Exception:
# If even error display fails, log and continue
self.logger.critical("Failed to display error message")
def _display_no_data(self):
"""Display a message when no data is available."""
self.display_manager.clear()
self.display_manager.draw_text(
"No data",
x=10, y=16,
color=(128, 128, 128)
)
self.display_manager.update_display()
```
### Validation Error Handling
```python
def validate_config(self) -> bool:
"""Validate plugin configuration."""
try:
# Check required fields
required_fields = ['api_key', 'city']
for field in required_fields:
if field not in self.config or not self.config[field]:
self.logger.error(f"Missing required field: {field}")
return False
# Validate field types
if not isinstance(self.config.get('display_duration'), (int, float)):
self.logger.error("display_duration must be a number")
return False
# Validate ranges
duration = self.config.get('display_duration', 15)
if duration < 1 or duration > 300:
self.logger.error("display_duration must be between 1 and 300 seconds")
return False
return True
except Exception as e:
self.logger.error(f"Error validating config: {e}", exc_info=True)
return False
```
---
## Performance Optimization
Optimize plugin performance for smooth operation on Raspberry Pi hardware.
### Efficient Data Fetching
```python
def update(self):
# Only fetch if cache is stale
cache_key = f"{self.plugin_id}_data"
cached = self.cache_manager.get(cache_key, max_age=3600)
if cached and self._is_data_fresh(cached):
self.data = cached
return
# Fetch only what's needed
try:
# Use appropriate cache strategy
self.data = self._fetch_minimal_data()
self.cache_manager.set(cache_key, self.data)
except Exception as e:
self.logger.error(f"Update failed: {e}")
# Use stale cache if available (re-fetch with large max_age to bypass expiration)
expired_cached = self.cache_manager.get(cache_key, max_age=31536000) # 1 year
if expired_cached:
self.data = expired_cached
self.logger.warning("Using stale cached data due to update failure")
```
### Optimized Rendering
```python
def display(self, force_clear=False):
# Only clear if necessary
if force_clear:
self.display_manager.clear()
else:
# Reuse existing canvas when possible
pass
# Batch drawing operations
self._draw_background()
self._draw_content()
self._draw_overlay()
# Single update call at the end
self.display_manager.update_display()
```
### Memory Management
```python
def cleanup(self):
"""Clean up resources to free memory."""
# Clear large data structures
if hasattr(self, 'large_cache'):
self.large_cache.clear()
# Close connections
if hasattr(self, 'api_client'):
self.api_client.close()
# Stop threads
if hasattr(self, 'worker_thread'):
self.worker_thread.stop()
super().cleanup()
```
### Lazy Loading
```python
def __init__(self, plugin_id, config, display_manager, cache_manager, plugin_manager):
super().__init__(plugin_id, config, display_manager, cache_manager, plugin_manager)
self._heavy_resource = None # Load on demand
def _get_heavy_resource(self):
"""Lazy load expensive resource."""
if self._heavy_resource is None:
self._heavy_resource = self._load_expensive_resource()
return self._heavy_resource
```
---
## Testing Plugins with Mocks
Use mock objects for testing plugins without hardware dependencies.
### Basic Mock Setup
```python
from src.plugin_system.testing.mocks import MockDisplayManager, MockCacheManager, MockPluginManager
def test_plugin_display():
# Create mocks
display_manager = MockDisplayManager()
cache_manager = MockCacheManager()
plugin_manager = MockPluginManager()
# Create plugin instance
config = {"enabled": True, "display_duration": 15}
plugin = MyPlugin("my-plugin", config, display_manager, cache_manager, plugin_manager)
# Test display
plugin.display(force_clear=True)
# Verify display calls
assert len(display_manager.draw_calls) > 0
assert display_manager.draw_calls[0]['text'] == "Hello"
```
### Testing Cache Behavior
```python
def test_plugin_caching():
cache_manager = MockCacheManager()
plugin = MyPlugin("my-plugin", config, display_manager, cache_manager, plugin_manager)
# Test cache miss
plugin.update()
assert len(cache_manager.get_calls) > 0
assert len(cache_manager.set_calls) > 0
# Test cache hit
cache_manager.set("my-plugin_data", {"test": "data"})
plugin.update()
# Verify no API call was made
```
### Testing Error Handling
```python
def test_error_handling():
display_manager = MockDisplayManager()
cache_manager = MockCacheManager()
plugin = MyPlugin("my-plugin", config, display_manager, cache_manager, plugin_manager)
# Simulate API error
with patch('plugin._fetch_from_api', side_effect=Exception("API Error")):
plugin.update()
# Verify plugin handles error gracefully
assert plugin.data is not None or hasattr(plugin, 'error_state')
```
---
## Inter-Plugin Communication
Plugins can communicate with each other through the Plugin Manager.
### Getting Data from Another Plugin
```python
def update(self):
# Get weather data from weather plugin
weather_plugin = self.plugin_manager.get_plugin("weather")
if weather_plugin and hasattr(weather_plugin, 'current_temp'):
self.weather_temp = weather_plugin.current_temp
self.logger.info(f"Got temperature from weather plugin: {self.weather_temp}")
```
### Checking Plugin Status
```python
def update(self):
# get_enabled_plugins() was removed in 3.8.0 — check the instance's
# `enabled` flag instead
weather_plugin = self.plugin_manager.get_plugin("weather")
if weather_plugin is not None and weather_plugin.enabled:
# Use weather data
pass
```
### Sharing Data Between Plugins
```python
class MyPlugin(BasePlugin):
def __init__(self, ...):
super().__init__(...)
self.shared_data = {} # Data accessible to other plugins
def update(self):
self.shared_data['last_update'] = time.time()
self.shared_data['status'] = 'active'
# In another plugin
def update(self):
my_plugin = self.plugin_manager.get_plugin("my-plugin")
if my_plugin and hasattr(my_plugin, 'shared_data'):
status = my_plugin.shared_data.get('status')
self.logger.info(f"MyPlugin status: {status}")
```
---
## Live Priority Implementation
Implement live priority to automatically take over the display when your plugin has urgent content.
### Basic Live Priority
```python
class MyPlugin(BasePlugin):
def __init__(self, ...):
super().__init__(...)
# Enable live priority in config
# "live_priority": true
def has_live_content(self) -> bool:
"""Check if plugin has live content."""
# Check for live games, breaking news, etc.
return hasattr(self, 'live_items') and len(self.live_items) > 0
def get_live_modes(self) -> List[str]:
"""Return modes to show during live priority."""
return ['live_mode'] # Only show live mode, not other modes
```
### Sports Plugin Example
```python
class SportsPlugin(BasePlugin):
def has_live_content(self) -> bool:
"""Check if there are any live games."""
if not hasattr(self, 'games'):
return False
for game in self.games:
if game.get('status') == 'live':
return True
return False
def get_live_modes(self) -> List[str]:
"""Only show live game modes during live priority."""
return ['nhl_live', 'nba_live'] # Exclude recent/upcoming modes
```
### News Plugin Example
```python
class NewsPlugin(BasePlugin):
def has_live_content(self) -> bool:
"""Check for breaking news."""
if not hasattr(self, 'headlines'):
return False
# Check for breaking news flag
for headline in self.headlines:
if headline.get('breaking', False):
return True
return False
def get_live_modes(self) -> List[str]:
"""Show breaking news mode during live priority."""
return ['breaking_news']
```
---
## Dynamic Duration Support
Implement dynamic duration to extend display time until content cycle completes.
### Basic Dynamic Duration
```python
class MyPlugin(BasePlugin):
def __init__(self, ...):
super().__init__(...)
self.current_step = 0
self.total_steps = 5
def supports_dynamic_duration(self) -> bool:
"""Enable dynamic duration in config."""
return self.config.get('dynamic_duration', {}).get('enabled', False)
def is_cycle_complete(self) -> bool:
"""Return True when all content has been shown."""
return self.current_step >= self.total_steps
def reset_cycle_state(self) -> None:
"""Reset cycle tracking when starting new display session."""
self.current_step = 0
def display(self, force_clear=False):
if force_clear:
self.display_manager.clear()
self.reset_cycle_state()
# Display current step
self._display_step(self.current_step)
self.display_manager.update_display()
# Advance to next step
self.current_step += 1
```
### Scrolling Content Example
```python
class ScrollingPlugin(BasePlugin):
def __init__(self, ...):
super().__init__(...)
self.scroll_position = 0
self.scroll_complete = False
def supports_dynamic_duration(self) -> bool:
return True
def is_cycle_complete(self) -> bool:
"""Return True when scrolling is complete."""
return self.scroll_complete
def reset_cycle_state(self) -> None:
"""Reset scroll state."""
self.scroll_position = 0
self.scroll_complete = False
def display(self, force_clear=False):
if force_clear:
self.display_manager.clear()
self.reset_cycle_state()
# Scroll content
text = "Long scrolling message..."
text_width = self.display_manager.get_text_width(text, self.display_manager.regular_font)
if self.scroll_position < -text_width:
# Scrolling complete
self.scroll_complete = True
else:
self.display_manager.clear()
self.display_manager.draw_text(
text,
x=self.scroll_position,
y=16
)
self.display_manager.update_display()
self.scroll_position -= 2
```
---
## See Also
- [Plugin API Reference](PLUGIN_API_REFERENCE.md) - Complete API documentation
- [Plugin Development Guide](PLUGIN_DEVELOPMENT_GUIDE.md) - Development workflow
- [Plugin Architecture Spec](PLUGIN_ARCHITECTURE_SPEC.md) - System architecture
- [BasePlugin Source](../src/plugin_system/base_plugin.py) - Base class implementation
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