Files
fast-next-template/backend/app/services/context/assembly/pipeline.py
Felipe Cardoso 1628eacf2b feat(context): enhance timeout handling, tenant isolation, and budget management
- Added timeout enforcement for token counting, scoring, and compression with detailed error handling.
- Introduced tenant isolation in context caching using project and agent identifiers.
- Enhanced budget management with stricter checks for critical context overspending and buffer limitations.
- Optimized per-context locking with cleanup to prevent memory leaks in concurrent environments.
- Updated default assembly timeout settings for improved performance and reliability.
- Improved XML escaping in Claude adapter for safety against injection attacks.
- Standardized token estimation using model-specific ratios.
2026-01-04 15:52:50 +01:00

363 lines
13 KiB
Python

"""
Context Assembly Pipeline.
Orchestrates the full context assembly workflow:
Gather → Count → Score → Rank → Compress → Format
"""
import asyncio
import logging
import time
from dataclasses import dataclass, field
from datetime import UTC, datetime
from typing import TYPE_CHECKING, Any
from ..adapters import get_adapter
from ..budget import BudgetAllocator, TokenBudget, TokenCalculator
from ..compression.truncation import ContextCompressor
from ..config import ContextSettings, get_context_settings
from ..exceptions import AssemblyTimeoutError
from ..prioritization import ContextRanker
from ..scoring import CompositeScorer
from ..types import AssembledContext, BaseContext, ContextType
if TYPE_CHECKING:
from app.services.mcp.client_manager import MCPClientManager
logger = logging.getLogger(__name__)
@dataclass
class PipelineMetrics:
"""Metrics from pipeline execution."""
start_time: datetime = field(default_factory=lambda: datetime.now(UTC))
end_time: datetime | None = None
total_contexts: int = 0
selected_contexts: int = 0
excluded_contexts: int = 0
compressed_contexts: int = 0
total_tokens: int = 0
assembly_time_ms: float = 0.0
scoring_time_ms: float = 0.0
compression_time_ms: float = 0.0
formatting_time_ms: float = 0.0
def to_dict(self) -> dict[str, Any]:
"""Convert to dictionary."""
return {
"start_time": self.start_time.isoformat(),
"end_time": self.end_time.isoformat() if self.end_time else None,
"total_contexts": self.total_contexts,
"selected_contexts": self.selected_contexts,
"excluded_contexts": self.excluded_contexts,
"compressed_contexts": self.compressed_contexts,
"total_tokens": self.total_tokens,
"assembly_time_ms": round(self.assembly_time_ms, 2),
"scoring_time_ms": round(self.scoring_time_ms, 2),
"compression_time_ms": round(self.compression_time_ms, 2),
"formatting_time_ms": round(self.formatting_time_ms, 2),
}
class ContextPipeline:
"""
Context assembly pipeline.
Orchestrates the full workflow of context assembly:
1. Validate and count tokens for all contexts
2. Score contexts based on relevance, recency, and priority
3. Rank and select contexts within budget
4. Compress if needed to fit remaining budget
5. Format for the target model
"""
def __init__(
self,
mcp_manager: "MCPClientManager | None" = None,
settings: ContextSettings | None = None,
calculator: TokenCalculator | None = None,
scorer: CompositeScorer | None = None,
ranker: ContextRanker | None = None,
compressor: ContextCompressor | None = None,
) -> None:
"""
Initialize the context pipeline.
Args:
mcp_manager: MCP client manager for LLM Gateway integration
settings: Context settings
calculator: Token calculator
scorer: Context scorer
ranker: Context ranker
compressor: Context compressor
"""
self._settings = settings or get_context_settings()
self._mcp = mcp_manager
# Initialize components
self._calculator = calculator or TokenCalculator(mcp_manager=mcp_manager)
self._scorer = scorer or CompositeScorer(
mcp_manager=mcp_manager, settings=self._settings
)
self._ranker = ranker or ContextRanker(
scorer=self._scorer, calculator=self._calculator
)
self._compressor = compressor or ContextCompressor(calculator=self._calculator)
self._allocator = BudgetAllocator(self._settings)
def set_mcp_manager(self, mcp_manager: "MCPClientManager") -> None:
"""Set MCP manager for all components."""
self._mcp = mcp_manager
self._calculator.set_mcp_manager(mcp_manager)
self._scorer.set_mcp_manager(mcp_manager)
async def assemble(
self,
contexts: list[BaseContext],
query: str,
model: str,
max_tokens: int | None = None,
custom_budget: TokenBudget | None = None,
compress: bool = True,
format_output: bool = True,
timeout_ms: int | None = None,
) -> AssembledContext:
"""
Assemble context for an LLM request.
This is the main entry point for context assembly.
Args:
contexts: List of contexts to assemble
query: Query to optimize for
model: Target model name
max_tokens: Maximum total tokens (uses model default if None)
custom_budget: Optional pre-configured budget
compress: Whether to compress oversized contexts
format_output: Whether to format the final output
timeout_ms: Maximum assembly time in milliseconds
Returns:
AssembledContext with optimized content
Raises:
AssemblyTimeoutError: If assembly exceeds timeout
"""
timeout = timeout_ms or self._settings.max_assembly_time_ms
start = time.perf_counter()
metrics = PipelineMetrics(total_contexts=len(contexts))
try:
# Create or use budget
if custom_budget:
budget = custom_budget
elif max_tokens:
budget = self._allocator.create_budget(max_tokens)
else:
budget = self._allocator.create_budget_for_model(model)
# 1. Count tokens for all contexts (with timeout enforcement)
try:
await asyncio.wait_for(
self._ensure_token_counts(contexts, model),
timeout=self._remaining_timeout(start, timeout),
)
except TimeoutError:
elapsed_ms = (time.perf_counter() - start) * 1000
raise AssemblyTimeoutError(
message="Context assembly timed out during token counting",
elapsed_ms=elapsed_ms,
timeout_ms=timeout,
)
# Check timeout (handles edge case where operation finished just at limit)
self._check_timeout(start, timeout, "token counting")
# 2. Score and rank contexts (with timeout enforcement)
scoring_start = time.perf_counter()
try:
ranking_result = await asyncio.wait_for(
self._ranker.rank(
contexts=contexts,
query=query,
budget=budget,
model=model,
),
timeout=self._remaining_timeout(start, timeout),
)
except TimeoutError:
elapsed_ms = (time.perf_counter() - start) * 1000
raise AssemblyTimeoutError(
message="Context assembly timed out during scoring/ranking",
elapsed_ms=elapsed_ms,
timeout_ms=timeout,
)
metrics.scoring_time_ms = (time.perf_counter() - scoring_start) * 1000
selected_contexts = ranking_result.selected_contexts
metrics.selected_contexts = len(selected_contexts)
metrics.excluded_contexts = len(ranking_result.excluded)
# Check timeout
self._check_timeout(start, timeout, "scoring")
# 3. Compress if needed and enabled (with timeout enforcement)
if compress and self._needs_compression(selected_contexts, budget):
compression_start = time.perf_counter()
try:
selected_contexts = await asyncio.wait_for(
self._compressor.compress_contexts(
selected_contexts, budget, model
),
timeout=self._remaining_timeout(start, timeout),
)
except TimeoutError:
elapsed_ms = (time.perf_counter() - start) * 1000
raise AssemblyTimeoutError(
message="Context assembly timed out during compression",
elapsed_ms=elapsed_ms,
timeout_ms=timeout,
)
metrics.compression_time_ms = (
time.perf_counter() - compression_start
) * 1000
metrics.compressed_contexts = sum(
1 for c in selected_contexts if c.metadata.get("truncated", False)
)
# Check timeout
self._check_timeout(start, timeout, "compression")
# 4. Format output
formatting_start = time.perf_counter()
if format_output:
formatted_content = self._format_contexts(selected_contexts, model)
else:
formatted_content = "\n\n".join(c.content for c in selected_contexts)
metrics.formatting_time_ms = (time.perf_counter() - formatting_start) * 1000
# Calculate final metrics
total_tokens = sum(c.token_count or 0 for c in selected_contexts)
metrics.total_tokens = total_tokens
metrics.assembly_time_ms = (time.perf_counter() - start) * 1000
metrics.end_time = datetime.now(UTC)
return AssembledContext(
content=formatted_content,
total_tokens=total_tokens,
context_count=len(selected_contexts),
assembly_time_ms=metrics.assembly_time_ms,
model=model,
contexts=selected_contexts,
excluded_count=metrics.excluded_contexts,
metadata={
"metrics": metrics.to_dict(),
"query": query,
"budget": budget.to_dict(),
},
)
except AssemblyTimeoutError:
raise
except Exception as e:
logger.error(f"Context assembly failed: {e}", exc_info=True)
raise
async def _ensure_token_counts(
self,
contexts: list[BaseContext],
model: str | None = None,
) -> None:
"""Ensure all contexts have token counts."""
tasks = []
for context in contexts:
if context.token_count is None:
tasks.append(self._count_and_set(context, model))
if tasks:
await asyncio.gather(*tasks)
async def _count_and_set(
self,
context: BaseContext,
model: str | None = None,
) -> None:
"""Count tokens and set on context."""
count = await self._calculator.count_tokens(context.content, model)
context.token_count = count
def _needs_compression(
self,
contexts: list[BaseContext],
budget: TokenBudget,
) -> bool:
"""Check if any contexts exceed their type budget."""
# Group by type and check totals
by_type: dict[ContextType, int] = {}
for context in contexts:
ct = context.get_type()
by_type[ct] = by_type.get(ct, 0) + (context.token_count or 0)
for ct, total in by_type.items():
if total > budget.get_allocation(ct):
return True
# Also check if utilization exceeds threshold
return budget.utilization() > self._settings.compression_threshold
def _format_contexts(
self,
contexts: list[BaseContext],
model: str,
) -> str:
"""
Format contexts for the target model.
Uses model-specific adapters (ClaudeAdapter, OpenAIAdapter, etc.)
to format contexts optimally for each model family.
Args:
contexts: Contexts to format
model: Target model name
Returns:
Formatted context string
"""
adapter = get_adapter(model)
return adapter.format(contexts)
def _check_timeout(
self,
start: float,
timeout_ms: int,
phase: str,
) -> None:
"""Check if timeout exceeded and raise if so."""
elapsed_ms = (time.perf_counter() - start) * 1000
if elapsed_ms >= timeout_ms:
raise AssemblyTimeoutError(
message=f"Context assembly timed out during {phase}",
elapsed_ms=elapsed_ms,
timeout_ms=timeout_ms,
)
def _remaining_timeout(self, start: float, timeout_ms: int) -> float:
"""
Calculate remaining timeout in seconds for asyncio.wait_for.
Returns at least a small positive value to avoid immediate timeout
edge cases with wait_for.
Args:
start: Start time from time.perf_counter()
timeout_ms: Total timeout in milliseconds
Returns:
Remaining timeout in seconds (minimum 0.001)
"""
elapsed_ms = (time.perf_counter() - start) * 1000
remaining_ms = timeout_ms - elapsed_ms
# Return at least 1ms to avoid zero/negative timeout edge cases
return max(remaining_ms / 1000.0, 0.001)