Files
Mainline/engine/pipeline/controller.py
David Gwilliam d54147cfb4 fix: DisplayStage dependency and render pipeline data flow
Critical fix for display rendering:

1. DisplayStage Missing Dependency
   - DisplayStage had empty dependencies, causing it to execute before render
   - No data was reaching the display output
   - Fix: Add 'render.output' dependency so display comes after render stages
   - Now proper execution order: source → render → display

2. create_default_pipeline Missing Render Stage
   - Default pipeline only had source and display, no render stage between
   - Would fail validation with 'Missing render.output' capability
   - Fix: Add SourceItemsToBufferStage to convert items to text buffer
   - Now complete data flow: source → render → display

3. Updated Test Expectations
   - test_display_stage_dependencies now expects 'render.output' dependency

Result: Display backends (pygame, terminal, websocket) now receive proper
rendered text buffers and can display output correctly.

Tests: All 502 tests passing
2026-03-16 21:59:52 -07:00

543 lines
18 KiB
Python

"""
Pipeline controller - DAG-based pipeline execution.
The Pipeline class orchestrates stages in dependency order, handling
the complete render cycle from source to display.
"""
import time
from dataclasses import dataclass, field
from typing import Any
from engine.pipeline.core import PipelineContext, Stage, StageError, StageResult
from engine.pipeline.params import PipelineParams
from engine.pipeline.registry import StageRegistry
@dataclass
class PipelineConfig:
"""Configuration for a pipeline instance."""
source: str = "headlines"
display: str = "terminal"
camera: str = "vertical"
effects: list[str] = field(default_factory=list)
enable_metrics: bool = True
@dataclass
class StageMetrics:
"""Metrics for a single stage execution."""
name: str
duration_ms: float
chars_in: int = 0
chars_out: int = 0
@dataclass
class FrameMetrics:
"""Metrics for a single frame through the pipeline."""
frame_number: int
total_ms: float
stages: list[StageMetrics] = field(default_factory=list)
class Pipeline:
"""Main pipeline orchestrator.
Manages the execution of all stages in dependency order,
handling initialization, processing, and cleanup.
"""
def __init__(
self,
config: PipelineConfig | None = None,
context: PipelineContext | None = None,
):
self.config = config or PipelineConfig()
self.context = context or PipelineContext()
self._stages: dict[str, Stage] = {}
self._execution_order: list[str] = []
self._initialized = False
self._metrics_enabled = self.config.enable_metrics
self._frame_metrics: list[FrameMetrics] = []
self._max_metrics_frames = 60
self._current_frame_number = 0
def add_stage(self, name: str, stage: Stage) -> "Pipeline":
"""Add a stage to the pipeline."""
self._stages[name] = stage
return self
def remove_stage(self, name: str) -> None:
"""Remove a stage from the pipeline."""
if name in self._stages:
del self._stages[name]
def get_stage(self, name: str) -> Stage | None:
"""Get a stage by name."""
return self._stages.get(name)
def build(self) -> "Pipeline":
"""Build execution order based on dependencies."""
self._capability_map = self._build_capability_map()
self._execution_order = self._resolve_dependencies()
self._validate_dependencies()
self._validate_types()
self._initialized = True
return self
def _build_capability_map(self) -> dict[str, list[str]]:
"""Build a map of capabilities to stage names.
Returns:
Dict mapping capability -> list of stage names that provide it
"""
capability_map: dict[str, list[str]] = {}
for name, stage in self._stages.items():
for cap in stage.capabilities:
if cap not in capability_map:
capability_map[cap] = []
capability_map[cap].append(name)
return capability_map
def _find_stage_with_capability(self, capability: str) -> str | None:
"""Find a stage that provides the given capability.
Supports wildcard matching:
- "source" matches "source.headlines" (prefix match)
- "source.*" matches "source.headlines"
- "source.headlines" matches exactly
Args:
capability: The capability to find
Returns:
Stage name that provides the capability, or None if not found
"""
# Exact match
if capability in self._capability_map:
return self._capability_map[capability][0]
# Prefix match (e.g., "source" -> "source.headlines")
for cap, stages in self._capability_map.items():
if cap.startswith(capability + "."):
return stages[0]
# Wildcard match (e.g., "source.*" -> "source.headlines")
if ".*" in capability:
prefix = capability[:-2] # Remove ".*"
for cap in self._capability_map:
if cap.startswith(prefix + "."):
return self._capability_map[cap][0]
return None
def _resolve_dependencies(self) -> list[str]:
"""Resolve stage execution order using topological sort with capability matching."""
ordered = []
visited = set()
temp_mark = set()
def visit(name: str) -> None:
if name in temp_mark:
raise StageError(name, "Circular dependency detected")
if name in visited:
return
temp_mark.add(name)
stage = self._stages.get(name)
if stage:
for dep in stage.dependencies:
# Find a stage that provides this capability
dep_stage_name = self._find_stage_with_capability(dep)
if dep_stage_name:
visit(dep_stage_name)
temp_mark.remove(name)
visited.add(name)
ordered.append(name)
for name in self._stages:
if name not in visited:
visit(name)
return ordered
def _validate_dependencies(self) -> None:
"""Validate that all dependencies can be satisfied.
Raises StageError if any dependency cannot be resolved.
"""
missing: list[tuple[str, str]] = [] # (stage_name, capability)
for name, stage in self._stages.items():
for dep in stage.dependencies:
if not self._find_stage_with_capability(dep):
missing.append((name, dep))
if missing:
msgs = [f" - {stage} needs {cap}" for stage, cap in missing]
raise StageError(
"validation",
"Missing capabilities:\n" + "\n".join(msgs),
)
def _validate_types(self) -> None:
"""Validate inlet/outlet types between connected stages.
PureData-style type validation. Each stage declares its inlet_types
(what it accepts) and outlet_types (what it produces). This method
validates that connected stages have compatible types.
Raises StageError if type mismatch is detected.
"""
from engine.pipeline.core import DataType
errors: list[str] = []
for i, name in enumerate(self._execution_order):
stage = self._stages.get(name)
if not stage:
continue
inlet_types = stage.inlet_types
# Check against previous stage's outlet types
if i > 0:
prev_name = self._execution_order[i - 1]
prev_stage = self._stages.get(prev_name)
if prev_stage:
prev_outlets = prev_stage.outlet_types
# Check if any outlet type is accepted by this inlet
compatible = (
DataType.ANY in inlet_types
or DataType.ANY in prev_outlets
or bool(prev_outlets & inlet_types)
)
if not compatible:
errors.append(
f" - {name} (inlet: {inlet_types}) "
f"{prev_name} (outlet: {prev_outlets})"
)
# Check display/sink stages (should accept TEXT_BUFFER)
if (
stage.category == "display"
and DataType.TEXT_BUFFER not in inlet_types
and DataType.ANY not in inlet_types
):
errors.append(f" - {name} is display but doesn't accept TEXT_BUFFER")
if errors:
raise StageError(
"type_validation",
"Type mismatch in pipeline connections:\n" + "\n".join(errors),
)
def initialize(self) -> bool:
"""Initialize all stages in execution order."""
for name in self._execution_order:
stage = self._stages.get(name)
if stage and not stage.init(self.context) and not stage.optional:
return False
return True
def execute(self, data: Any | None = None) -> StageResult:
"""Execute the pipeline with the given input data.
Pipeline execution:
1. Execute all non-overlay stages in dependency order
2. Apply overlay stages on top (sorted by render_order)
"""
if not self._initialized:
self.build()
if not self._initialized:
return StageResult(
success=False,
data=None,
error="Pipeline not initialized",
)
current_data = data
frame_start = time.perf_counter() if self._metrics_enabled else 0
stage_timings: list[StageMetrics] = []
# Separate overlay stages from regular stages
overlay_stages: list[tuple[int, Stage]] = []
regular_stages: list[str] = []
for name in self._execution_order:
stage = self._stages.get(name)
if not stage or not stage.is_enabled():
continue
# Safely check is_overlay - handle MagicMock and other non-bool returns
try:
is_overlay = bool(getattr(stage, "is_overlay", False))
except Exception:
is_overlay = False
if is_overlay:
# Safely get render_order
try:
render_order = int(getattr(stage, "render_order", 0))
except Exception:
render_order = 0
overlay_stages.append((render_order, stage))
else:
regular_stages.append(name)
# Execute regular stages in dependency order
for name in regular_stages:
stage = self._stages.get(name)
if not stage or not stage.is_enabled():
continue
stage_start = time.perf_counter() if self._metrics_enabled else 0
try:
current_data = stage.process(current_data, self.context)
except Exception as e:
if not stage.optional:
return StageResult(
success=False,
data=current_data,
error=str(e),
stage_name=name,
)
continue
if self._metrics_enabled:
stage_duration = (time.perf_counter() - stage_start) * 1000
chars_in = len(str(data)) if data else 0
chars_out = len(str(current_data)) if current_data else 0
stage_timings.append(
StageMetrics(
name=name,
duration_ms=stage_duration,
chars_in=chars_in,
chars_out=chars_out,
)
)
# Apply overlay stages (sorted by render_order)
overlay_stages.sort(key=lambda x: x[0])
for render_order, stage in overlay_stages:
stage_start = time.perf_counter() if self._metrics_enabled else 0
stage_name = f"[overlay]{stage.name}"
try:
# Overlays receive current_data but don't pass their output to next stage
# Instead, their output is composited on top
overlay_output = stage.process(current_data, self.context)
# For now, we just let the overlay output pass through
# In a more sophisticated implementation, we'd composite it
if overlay_output is not None:
current_data = overlay_output
except Exception as e:
if not stage.optional:
return StageResult(
success=False,
data=current_data,
error=str(e),
stage_name=stage_name,
)
if self._metrics_enabled:
stage_duration = (time.perf_counter() - stage_start) * 1000
chars_in = len(str(data)) if data else 0
chars_out = len(str(current_data)) if current_data else 0
stage_timings.append(
StageMetrics(
name=stage_name,
duration_ms=stage_duration,
chars_in=chars_in,
chars_out=chars_out,
)
)
if self._metrics_enabled:
total_duration = (time.perf_counter() - frame_start) * 1000
self._frame_metrics.append(
FrameMetrics(
frame_number=self._current_frame_number,
total_ms=total_duration,
stages=stage_timings,
)
)
# Store metrics in context for other stages (like HUD)
# This makes metrics a first-class pipeline citizen
if self.context:
self.context.state["metrics"] = self.get_metrics_summary()
if len(self._frame_metrics) > self._max_metrics_frames:
self._frame_metrics.pop(0)
self._current_frame_number += 1
return StageResult(success=True, data=current_data)
def cleanup(self) -> None:
"""Clean up all stages in reverse order."""
for name in reversed(self._execution_order):
stage = self._stages.get(name)
if stage:
try:
stage.cleanup()
except Exception:
pass
self._stages.clear()
self._initialized = False
@property
def stages(self) -> dict[str, Stage]:
"""Get all stages."""
return self._stages.copy()
@property
def execution_order(self) -> list[str]:
"""Get execution order."""
return self._execution_order.copy()
def get_stage_names(self) -> list[str]:
"""Get list of stage names."""
return list(self._stages.keys())
def get_overlay_stages(self) -> list[Stage]:
"""Get all overlay stages sorted by render_order."""
overlays = [stage for stage in self._stages.values() if stage.is_overlay]
overlays.sort(key=lambda s: s.render_order)
return overlays
def get_stage_type(self, name: str) -> str:
"""Get the stage_type for a stage."""
stage = self._stages.get(name)
return stage.stage_type if stage else ""
def get_render_order(self, name: str) -> int:
"""Get the render_order for a stage."""
stage = self._stages.get(name)
return stage.render_order if stage else 0
def get_metrics_summary(self) -> dict:
"""Get summary of collected metrics."""
if not self._frame_metrics:
return {"error": "No metrics collected"}
total_times = [f.total_ms for f in self._frame_metrics]
avg_total = sum(total_times) / len(total_times)
min_total = min(total_times)
max_total = max(total_times)
stage_stats: dict[str, dict] = {}
for frame in self._frame_metrics:
for stage in frame.stages:
if stage.name not in stage_stats:
stage_stats[stage.name] = {"times": [], "total_chars": 0}
stage_stats[stage.name]["times"].append(stage.duration_ms)
stage_stats[stage.name]["total_chars"] += stage.chars_out
for name, stats in stage_stats.items():
times = stats["times"]
stats["avg_ms"] = sum(times) / len(times)
stats["min_ms"] = min(times)
stats["max_ms"] = max(times)
del stats["times"]
return {
"frame_count": len(self._frame_metrics),
"pipeline": {
"avg_ms": avg_total,
"min_ms": min_total,
"max_ms": max_total,
},
"stages": stage_stats,
}
def reset_metrics(self) -> None:
"""Reset collected metrics."""
self._frame_metrics.clear()
self._current_frame_number = 0
def get_frame_times(self) -> list[float]:
"""Get historical frame times for sparklines/charts."""
return [f.total_ms for f in self._frame_metrics]
class PipelineRunner:
"""High-level pipeline runner with animation support."""
def __init__(
self,
pipeline: Pipeline,
params: PipelineParams | None = None,
):
self.pipeline = pipeline
self.params = params or PipelineParams()
self._running = False
def start(self) -> bool:
"""Start the pipeline."""
self._running = True
return self.pipeline.initialize()
def step(self, input_data: Any | None = None) -> Any:
"""Execute one pipeline step."""
self.params.frame_number += 1
self.pipeline.context.params = self.params
result = self.pipeline.execute(input_data)
return result.data if result.success else None
def stop(self) -> None:
"""Stop and clean up the pipeline."""
self._running = False
self.pipeline.cleanup()
@property
def is_running(self) -> bool:
"""Check if runner is active."""
return self._running
def create_pipeline_from_params(params: PipelineParams) -> Pipeline:
"""Create a pipeline from PipelineParams."""
config = PipelineConfig(
source=params.source,
display=params.display,
camera=params.camera_mode,
effects=params.effect_order,
)
return Pipeline(config=config)
def create_default_pipeline() -> Pipeline:
"""Create a default pipeline with all standard components."""
from engine.data_sources.sources import HeadlinesDataSource
from engine.pipeline.adapters import (
DataSourceStage,
SourceItemsToBufferStage,
)
pipeline = Pipeline()
# Add source stage (wrapped as Stage)
source = HeadlinesDataSource()
pipeline.add_stage("source", DataSourceStage(source, name="headlines"))
# Add render stage to convert items to text buffer
pipeline.add_stage("render", SourceItemsToBufferStage(name="items-to-buffer"))
# Add display stage
display = StageRegistry.create("display", "terminal")
if display:
pipeline.add_stage("display", display)
return pipeline.build()