Files
NSCT---Neutral-Search-Crawl…/src/nsct/logging_config.py
NSCT Agent 08ec0e290c feat(stage16): implement observability — structured logging, metrics, tracing
- JSONFormatter, ContextVars, set_research_run_id() with short logger names
- self-built Counter/Histogram/Gauge system (no external deps)
- Prometheus text export at /metrics
- Request logging middleware with X-Request-ID
- Metrics instrumentation: search_queries, sources_fetched, claims, contradictions
- Histograms: research_duration, llm_request_duration
- Gauge: active_research_runs
- 13 + 21 = 34 tests
2026-08-27 19:44:46 +00:00

236 lines
7.3 KiB
Python

"""Structured logging for NSCT — JSONLines formatter, module loggers, env-config.
Environment variables
---------------------
NSCT_LOG_LEVEL — Log level string (DEBUG, INFO, WARNING, ERROR, CRITICAL).
Default: INFO.
NSCT_LOG_FILE — If set, write JSON logs to this file instead of stdout.
When unset, logs go to stdout.
Usage
-----
from nsct.logging_config import get_logger, setup_logging
setup_logging() # call once at app bootstrap
logger = get_logger(__name__) # any module
logger.info("started", research_run_id="abc")
"""
from __future__ import annotations
import json
import logging
import os
import sys
import time
import uuid
from contextvars import ContextVar
from typing import Any
from nsct import __version__
# ---------------------------------------------------------------------------
# Per-request / per-run context (ContextVar for async safety)
# ---------------------------------------------------------------------------
# Legacy dict-based context (kept for backward compat with existing callers)
_request_ctx: dict[str, str] = {}
_request_ctx_token: ContextVar[dict[str, Any]] = ContextVar("_request_ctx", default={})
def set_request_ctx(**kwargs: str) -> None:
"""Set (merge) key-value pairs into the per-request context dict."""
_request_ctx.update(kwargs)
ctx = _request_ctx_token.get()
ctx.update(kwargs)
_request_ctx_token.set(ctx)
def clear_request_ctx() -> None:
"""Clear all per-request context entries."""
_request_ctx.clear()
_request_ctx_token.set({})
# ---------------------------------------------------------------------------
# Helpers: research_run_id convenience
# ---------------------------------------------------------------------------
_research_run_id: ContextVar[str | None] = ContextVar("_research_run_id", default=None)
def set_research_run_id(run_id: str) -> None:
_research_run_id.set(run_id)
def get_research_run_id() -> str | None:
return _research_run_id.get()
def clear_research_run_id() -> None:
_research_run_id.set(None)
def get_stage_ctx() -> str | None:
"""Read the 'stage' value from the active context dict."""
return _request_ctx.get("stage")
# ---------------------------------------------------------------------------
# JSON Formatter — JSONLines with research_run_id, stage, etc.
# ---------------------------------------------------------------------------
class JSONFormatter(logging.Formatter):
"""Emit log records as one JSON object per line (JSONLines)."""
default_fmt: str = ""
def __init__(self, *args: Any, **kwargs: Any) -> None:
super().__init__(*args, **kwargs)
self._start_ts: float = time.monotonic()
def format(self, record: logging.LogRecord) -> str:
ts = time.strftime("%Y-%m-%dT%H:%M:%S", time.gmtime(record.created))
elapsed_ms = round((time.monotonic() - self._start_ts) * 1000, 2)
# Core fields
data: dict[str, Any] = {
"timestamp": ts,
"level": record.levelname,
"module": record.name,
"message": record.getMessage(),
"elapsed_ms": elapsed_ms,
"pid": record.process,
"thread": record.thread,
"function": record.funcName,
"line": record.lineno,
"version": __version__,
}
# Pull in the ContextVar-based request context
ctx = _request_ctx_token.get()
if ctx:
for k, v in ctx.items():
data[k] = v
# Legacy _request_ctx (for callers who only use set_request_ctx)
for k, v in _request_ctx.items():
if k not in data:
data[k] = v
# research_run_id and stage convenience
rid = get_research_run_id()
if rid and "research_run_id" not in data:
data["research_run_id"] = rid
# exception info
if record.exc_info and record.exc_info[0] is not None:
data["exc_info"] = self.formatException(record.exc_info)
return json.dumps(data, default=str, ensure_ascii=False)
# ---------------------------------------------------------------------------
# Bootstrap
# ---------------------------------------------------------------------------
_MODULE_LOGGERS: dict[str, logging.Logger] = {}
def _make_module_logger(name: str) -> logging.Logger:
"""Return (and cache) a pre-configured child logger."""
if name in _MODULE_LOGGERS:
return _MODULE_LOGGERS[name]
# Only create loggers for known top-level modules
known_prefixes = ("nsct.api", "nsct.orchestration", "nsct.stages", "nsct.cli")
is_known = any(name == p or name.startswith(p + ".") for p in known_prefixes)
logger = logging.getLogger(name)
if is_known:
_MODULE_LOGGERS[name] = logger
return logger
# Map short names → full module names
_MODULE_ALIASES = {
"api": "nsct.api",
"rest_research": "nsct.api.rest_research",
"orchestration": "nsct.orchestration",
"stages": "nsct.stages",
"cli": "nsct.cli",
"metrics": "nsct.metrics",
"logging_config": "nsct.logging_config",
}
def get_logger(name: str | None = None) -> logging.Logger:
"""Return a pre-configured child logger.
Short names (``api``, ``orchestration``, ``stages``, ``cli``) are
expanded to their full module path so they hit the known-prefix gate.
``None`` → ``nsct`` root.
"""
if name is None or name in _MODULE_ALIASES:
name = _MODULE_ALIASES.get(name, "nsct") if name else "nsct"
return _make_module_logger(name)
def setup_logging(
level: str | None = None,
json_format: bool = True,
) -> None:
"""Configure logging.
Reads *NSCT_LOG_LEVEL* and *NSCT_LOG_FILE* from the environment so
callers don't have to pass arguments.
Parameters
----------
level : str | None
Log level string. Defaults to ``NSCT_LOG_LEVEL`` env, then ``INFO``.
json_format : bool
If True, use JSONFormatter; else use a human-readable format.
"""
import os
effective_level = level or os.environ.get("NSCT_LOG_LEVEL", "INFO")
log_file = os.environ.get("NSCT_LOG_FILE")
log_level = getattr(logging, effective_level.upper(), logging.INFO)
root = logging.getLogger()
root.setLevel(log_level)
root.handlers.clear()
if log_file:
# File handler — JSONLines
fh = logging.FileHandler(log_file, encoding="utf-8")
fh.setLevel(log_level)
if json_format:
fh.setFormatter(JSONFormatter())
else:
fh.setFormatter(
logging.Formatter(
"%(asctime)s [%(levelname)-8s] %(name)s:%(funcName)s:%(lineno)d%(message)s",
datefmt="%Y-%m-%d %H:%M:%S",
)
)
root.addHandler(fh)
else:
# Console handler — JSONLines
ch = logging.StreamHandler(sys.stdout)
ch.setLevel(log_level)
if json_format:
ch.setFormatter(JSONFormatter())
else:
ch.setFormatter(
logging.Formatter(
"%(asctime)s [%(levelname)-8s] %(name)s:%(funcName)s:%(lineno)d%(message)s",
datefmt="%Y-%m-%d %H:%M:%S",
)
)
root.addHandler(ch)
# Quick-export for convenience
logger = get_logger()