# Copyright The OpenTelemetry Authors
# SPDX-License-Identifier: Apache-2.0
import re
from logging import getLogger
from opentelemetry.sdk.resources import Resource, ResourceDetector
from opentelemetry.semconv.resource import ResourceAttributes
logger = getLogger(__name__)
_DEFAULT_CGROUP_V1_PATH = "/proc/self/cgroup"
_DEFAULT_CGROUP_V2_PATH = "/proc/self/mountinfo"
_CONTAINER_ID_LENGTH = 64
def _get_container_id_v1():
container_id = None
try:
with open(
_DEFAULT_CGROUP_V1_PATH, encoding="utf8"
) as container_info_file:
for raw_line in container_info_file.readlines():
line = raw_line.strip()
match = re.search(
r"^.*/(?:.*[-:])?([0-9a-f]+)(?:\.|\s*$)", line
)
if match is not None:
container_id = match.group(1)
break
except FileNotFoundError as exception:
logger.debug("Failed to get container id. Exception: %s", exception)
return container_id
def _get_container_id_v2():
container_id = None
try:
with open(
_DEFAULT_CGROUP_V2_PATH, encoding="utf8"
) as container_info_file:
for raw_line in container_info_file.readlines():
line = raw_line.strip()
if any(
key_word in line for key_word in ["containers", "hostname"]
):
container_id_list = [
id_
for id_ in line.split("/")
if len(id_) == _CONTAINER_ID_LENGTH
]
if len(container_id_list) > 0:
container_id = container_id_list[0]
break
except FileNotFoundError as exception:
logger.debug("Failed to get container id. Exception: %s", exception)
return container_id
def _get_container_id():
return _get_container_id_v1() or _get_container_id_v2()
[docs]class ContainerResourceDetector(ResourceDetector):
"""Detects container.id only available when app is running inside the
docker container and return it in a Resource
"""
[docs] def detect(self) -> "Resource":
try:
container_id = _get_container_id()
resource = Resource.get_empty()
if container_id:
resource = resource.merge(
Resource({ResourceAttributes.CONTAINER_ID: container_id})
)
return resource
# pylint: disable=broad-except
except Exception as exception:
logger.warning(
"%s Resource Detection failed silently: %s",
self.__class__.__name__,
exception,
)
if self.raise_on_error:
raise exception
return Resource.get_empty()