Add codspeed benchmarks

.github/workflows/codspeed.yml

@@ -0,0 +1,46 @@
+---
+name: CodSpeed Benchmarks
+
+on:
+  push:
+    branches: [main]
+    tags: ["*"]
+    paths:
+      - src/**.py
+      - bench/**
+      - .github/workflows/codspeed.yml
+  pull_request:
+    paths:
+      - src/**.py
+      - bench/**
+      - .github/workflows/codspeed.yml
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+env:
+  FORCE_COLOR: "1"
+
+permissions: {}
+
+jobs:
+  codspeed:
+    name: Run CodSpeed benchmarks
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+      - uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
+        with:
+          python-version-file: .python-version-default
+      - uses: hynek/setup-cached-uv@34e35d30f1ebc7421a5cc733bca38dcc62603960 # v2.6.0
+
+      - name: Run CodSpeed benchmarks
+        uses: CodSpeedHQ/action@88472375d0a4572cf70a9f1fe3a4e0ab8da1b924 # v5.0.1
+        with:
+          mode: simulation
+          run: uvx --with tox-uv tox run -e codspeed

bench/test_benchmarks.py

@@ -0,0 +1,199 @@
+# SPDX-License-Identifier: MIT OR Apache-2.0
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the MIT License.  See the LICENSE file in the root of this
+# repository for complete details.
+
+"""
+Benchmark structlog using CodSpeed.
+"""
+
+from __future__ import annotations
+
+import logging
+
+import pytest
+
+import structlog
+
+
+pytestmark = pytest.mark.benchmark()
+
+ROUNDS = 1_000
+
+# A typical set of key/value pairs that gets bound to a logger in a web
+# application.
+KWARGS = {
+    "user_id": 42,
+    "request_id": "b1f2b3c4-d5e6-4f7a-8b9c-0d1e2f3a4b5c",
+    "path": "/api/v1/orders",
+    "method": "POST",
+    "status": 201,
+    "duration_ms": 12.34,
+}
+
+INFO_LOGGER_CLASS = structlog.make_filtering_bound_logger(logging.INFO)
+
+
+def make_logger(*processors):
+    """
+    Create a bound logger that filters at info level, runs *processors*, and
+    logs into the void.
+    """
+    return structlog.wrap_logger(
+        structlog.testing.ReturnLogger(),
+        processors=list(processors),
+        wrapper_class=INFO_LOGGER_CLASS,
+    ).bind()
+
+
+def test_create_bound_logger():
+    """
+    Benchmark wrapping a logger and binding initial values to it.
+    """
+    for _ in range(ROUNDS):
+        structlog.wrap_logger(
+            structlog.testing.ReturnLogger(),
+            processors=[structlog.processors.JSONRenderer()],
+            wrapper_class=INFO_LOGGER_CLASS,
+        ).bind(**KWARGS)
+
+
+def test_bind():
+    """
+    Benchmark binding key/value pairs to an existing bound logger.
+    """
+    log = make_logger(structlog.processors.JSONRenderer())
+
+    for _ in range(ROUNDS):
+        log.bind(**KWARGS)
+
+
+def test_log_event_json():
+    """
+    Benchmark logging an event through a typical production processor chain
+    that renders to JSON.
+    """
+    log = make_logger(
+        structlog.processors.add_log_level,
+        structlog.processors.StackInfoRenderer(),
+        structlog.processors.TimeStamper(fmt="iso", utc=True),
+        structlog.processors.JSONRenderer(),
+    ).bind(**KWARGS)
+
+    for _ in range(ROUNDS):
+        log.info("request handled")
+
+
+def test_log_event_console():
+    """
+    Benchmark logging an event using the development ConsoleRenderer.
+    """
+    log = make_logger(
+        structlog.processors.add_log_level,
+        structlog.processors.TimeStamper(fmt="%Y-%m-%d %H:%M.%S", utc=True),
+        structlog.dev.ConsoleRenderer(colors=True),
+    ).bind(**KWARGS)
+
+    for _ in range(ROUNDS):
+        log.info("request handled")
+
+
+def test_log_event_key_value():
+    """
+    Benchmark logging an event using the classic KeyValueRenderer.
+    """
+    log = make_logger(
+        structlog.processors.add_log_level,
+        structlog.processors.TimeStamper(fmt="iso", utc=True),
+        structlog.processors.KeyValueRenderer(
+            key_order=["timestamp", "level", "event"]
+        ),
+    ).bind(**KWARGS)
+
+    for _ in range(ROUNDS):
+        log.info("request handled")
+
+
+def test_log_event_filtered_out():
+    """
+    Benchmark a log call that gets dropped by the level filter.
+    """
+    log = make_logger(structlog.processors.JSONRenderer()).bind(**KWARGS)
+
+    for _ in range(ROUNDS):
+        log.debug("nobody will ever see this")
+
+
+def test_log_event_with_contextvars():
+    """
+    Benchmark logging an event that merges context-local values.
+    """
+    log = make_logger(
+        structlog.contextvars.merge_contextvars,
+        structlog.processors.JSONRenderer(),
+    )
+
+    structlog.contextvars.bind_contextvars(**KWARGS)
+
+    for _ in range(ROUNDS):
+        log.info("request handled")
+
+    structlog.contextvars.clear_contextvars()
+
+
+def test_bind_and_clear_contextvars():
+    """
+    Benchmark binding and clearing context-local values, like a middleware
+    does once per request.
+    """
+    for _ in range(ROUNDS):
+        structlog.contextvars.bind_contextvars(**KWARGS)
+        structlog.contextvars.clear_contextvars()
+
+
+def _bottom():
+    raise ValueError("d'oh")
+
+
+def _middle():
+    _bottom()
+
+
+def _top():
+    _middle()
+
+
+def test_log_exception_as_dict():
+    """
+    Benchmark extracting and rendering an exception into structured data
+    using dict_tracebacks.
+    """
+    log = make_logger(
+        structlog.processors.add_log_level,
+        structlog.processors.dict_tracebacks,
+        structlog.processors.JSONRenderer(),
+    ).bind(**KWARGS)
+
+    try:
+        _top()
+    except ValueError:
+        for _ in range(ROUNDS):
+            log.exception("cannot compute")
+
+
+def test_log_exception_formatted():
+    """
+    Benchmark formatting an exception into a traceback string using
+    format_exc_info.
+    """
+    log = make_logger(
+        structlog.processors.add_log_level,
+        structlog.processors.format_exc_info,
+        structlog.processors.JSONRenderer(),
+    ).bind(**KWARGS)
+
+    try:
+        _top()
+    except ValueError:
+        for _ in range(ROUNDS):
+            log.exception("cannot compute")

pyproject.toml

@@ -49,6 +49,11 @@ tests = [
 # Need Twisted & Rich for stubs.
 # Otherwise mypy fails in tox.
 typing = ["mypy>=1.4", "rich", "twisted"]
+benchmark = [
+    {include-group = "tests"},
+    "pytest-codspeed",
+    "pytest-xdist[psutil]",
+]
 docs = [
     "cogapp",
     "myst-parser",
@@ -186,9 +191,9 @@ ignore_errors = false
 
 # Analyze everything for LSP, but only complain about typing examples.
 [[tool.ty.overrides]]
-include = ["src", "tests"]
-exclude = ["tests/typing/"]
 rules.all = "ignore"
+include = ["src", "tests", "bench"]
+exclude = ["tests/typing/"]
 
 
 [tool.pyrefly]

tox.ini

@@ -52,6 +52,17 @@ deps = coverage
 commands = coverage report
 
 
+[testenv:codspeed]
+dependency_groups = benchmark
+pass_env =
+    CODSPEED_TOKEN
+    CODSPEED_ENV
+    ARCH
+    PYTHONHASHSEED
+    PYTHONMALLOC
+commands = pytest --codspeed -n auto bench/test_benchmarks.py
+
+
 [testenv:docs-{build,doctests,linkcheck}]
 # Keep base_python in sync with ci.yml/docs and .readthedocs.yaml.
 base_python = 3.14