opentelemetry-python-contrib/ddtrace/bootstrap/sitecustomize.py

"""
Bootstrapping code that is run when using the `ddtrace-run` Python entrypoint
Add all monkey-patching that needs to run by default here
"""

import os
import imp
import sys
import logging

from ddtrace.utils.formats import asbool, get_env
from ddtrace.internal.logger import get_logger
from ddtrace import constants

logs_injection = asbool(get_env("logs", "injection"))
DD_LOG_FORMAT = "%(asctime)s %(levelname)s [%(name)s] [%(filename)s:%(lineno)d] {}- %(message)s".format(
    "[dd.trace_id=%(dd.trace_id)s dd.span_id=%(dd.span_id)s] " if logs_injection else ""
)

if logs_injection:
    # immediately patch logging if trace id injected
    from ddtrace import patch

    patch(logging=True)

debug = os.environ.get("DATADOG_TRACE_DEBUG")

# Set here a default logging format for basicConfig

# DEV: Once basicConfig is called here, future calls to it cannot be used to
# change the formatter since it applies the formatter to the root handler only
# upon initializing it the first time.
# See https://github.com/python/cpython/blob/112e4afd582515fcdcc0cde5012a4866e5cfda12/Lib/logging/__init__.py#L1550
if debug and debug.lower() == "true":
    logging.basicConfig(level=logging.DEBUG, format=DD_LOG_FORMAT)
else:
    logging.basicConfig(format=DD_LOG_FORMAT)

log = get_logger(__name__)

EXTRA_PATCHED_MODULES = {
    "bottle": True,
    "django": True,
    "falcon": True,
    "flask": True,
    "pyramid": True,
}


def update_patched_modules():
    modules_to_patch = os.environ.get("DATADOG_PATCH_MODULES")
    if not modules_to_patch:
        return
    for patch in modules_to_patch.split(","):
        if len(patch.split(":")) != 2:
            log.debug("skipping malformed patch instruction")
            continue

        module, should_patch = patch.split(":")
        if should_patch.lower() not in ["true", "false"]:
            log.debug("skipping malformed patch instruction for %s", module)
            continue

        EXTRA_PATCHED_MODULES.update({module: should_patch.lower() == "true"})


def add_global_tags(tracer):
    tags = {}
    for tag in os.environ.get("DD_TRACE_GLOBAL_TAGS", "").split(","):
        tag_name, _, tag_value = tag.partition(":")
        if not tag_name or not tag_value:
            log.debug("skipping malformed tracer tag")
            continue

        tags[tag_name] = tag_value
    tracer.set_tags(tags)


try:
    from ddtrace import tracer

    patch = True

    # Respect DATADOG_* environment variables in global tracer configuration
    # TODO: these variables are deprecated; use utils method and update our documentation
    # correct prefix should be DD_*
    enabled = os.environ.get("DATADOG_TRACE_ENABLED")
    hostname = os.environ.get("DD_AGENT_HOST", os.environ.get("DATADOG_TRACE_AGENT_HOSTNAME"))
    port = os.environ.get("DATADOG_TRACE_AGENT_PORT")
    priority_sampling = os.environ.get("DATADOG_PRIORITY_SAMPLING")

    opts = {}

    if enabled and enabled.lower() == "false":
        opts["enabled"] = False
        patch = False
    if hostname:
        opts["hostname"] = hostname
    if port:
        opts["port"] = int(port)
    if priority_sampling:
        opts["priority_sampling"] = asbool(priority_sampling)

    opts["collect_metrics"] = asbool(get_env("runtime_metrics", "enabled"))

    if opts:
        tracer.configure(**opts)

    if logs_injection:
        EXTRA_PATCHED_MODULES.update({"logging": True})

    if patch:
        update_patched_modules()
        from ddtrace import patch_all

        patch_all(**EXTRA_PATCHED_MODULES)

    if "DATADOG_ENV" in os.environ:
        tracer.set_tags({constants.ENV_KEY: os.environ["DATADOG_ENV"]})

    if "DD_TRACE_GLOBAL_TAGS" in os.environ:
        add_global_tags(tracer)

    # Ensure sitecustomize.py is properly called if available in application directories:
    # * exclude `bootstrap_dir` from the search
    # * find a user `sitecustomize.py` module
    # * import that module via `imp`
    bootstrap_dir = os.path.dirname(__file__)
    path = list(sys.path)

    if bootstrap_dir in path:
        path.remove(bootstrap_dir)

    try:
        (f, path, description) = imp.find_module("sitecustomize", path)
    except ImportError:
        pass
    else:
        # `sitecustomize.py` found, load it
        log.debug("sitecustomize from user found in: %s", path)
        imp.load_module("sitecustomize", f, path, description)

    # Loading status used in tests to detect if the `sitecustomize` has been
    # properly loaded without exceptions. This must be the last action in the module
    # when the execution ends with a success.
    loaded = True
except Exception:
    loaded = False
    log.warning("error configuring Datadog tracing", exc_info=True)