[WIP] Make Client object globally available (#1043)

* Make Client object globally available * Remove global client object on Client.close() * Fix django's get_client to use elasticapm.get_client * Clean up more client creation * CHANGELOG

Author: basepi

CHANGELOG.asciidoc

@@ -37,6 +37,8 @@ endif::[]
 [float]
 ===== Features
 
+* Add global access to Client singleton object at `elasticapm.get_client()` {pull}1043[#1043]
+
 
 [float]
 ===== Bug fixes

elasticapm/__init__.py

@@ -29,7 +29,7 @@
 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 import sys
 
-from elasticapm.base import Client
+from elasticapm.base import Client, get_client # noqa: F401
 from elasticapm.conf import setup_logging # noqa: F401
 from elasticapm.instrumentation.control import instrument, uninstrument # noqa: F401
 from elasticapm.traces import ( # noqa: F401

elasticapm/base.py

@@ -54,6 +54,8 @@
 
 __all__ = ("Client",)
 
+CLIENT_SINGLETON = None
+
 
 class Client(object):
  """
@@ -205,6 +207,9 @@ def __init__(self, config=None, **inline):
  if config.enabled:
  self.start_threads()
 
+ # Save this Client object as the global CLIENT_SINGLETON
+ set_client(self)
+
  def start_threads(self):
  with self._thread_starter_lock:
  current_pid = os.getpid()
@@ -298,6 +303,8 @@ def close(self):
  with self._thread_starter_lock:
  for _, manager in self._thread_managers.items():
  manager.stop_thread()
+ global CLIENT_SINGLETON
+ CLIENT_SINGLETON = None
 
  def get_service_info(self):
  if self._service_info:
@@ -611,3 +618,15 @@ class DummyClient(Client):
 
  def send(self, url, **kwargs):
  return None
+
+
+def get_client():
+ return CLIENT_SINGLETON
+
+
+def set_client(client):
+ global CLIENT_SINGLETON
+ if CLIENT_SINGLETON:
+ logger = get_logger("elasticapm")
+ logger.debug("Client object is being set more than once")
+ CLIENT_SINGLETON = client

elasticapm/contrib/aiohttp/__init__.py

@@ -33,8 +33,6 @@
 import elasticapm
 from elasticapm import Client
 
-CLIENT_KEY = "_elasticapm_client_instance"
-
 
 class ElasticAPM:
  def __init__(self, app, client=None):
@@ -43,7 +41,6 @@ def __init__(self, app, client=None):
  config.setdefault("framework_name", "aiohttp")
  config.setdefault("framework_version", aiohttp.__version__)
  client = Client(config=config)
- app[CLIENT_KEY] = client
  self.app = app
  self.client = client
  self.install_tracing(app, client)

elasticapm/contrib/aiohttp/middleware.py

@@ -32,6 +32,7 @@
 from aiohttp.web import HTTPException, Response, middleware
 
 import elasticapm
+from elasticapm import get_client
 from elasticapm.conf import constants
 from elasticapm.contrib.aiohttp.utils import get_data_from_request, get_data_from_response
 from elasticapm.utils.disttracing import TraceParent
@@ -44,13 +45,10 @@ def merge_duplicate_headers(cls, headers, key):
 
 
 def tracing_middleware(app):
- from elasticapm.contrib.aiohttp import CLIENT_KEY # noqa
-
  async def handle_request(request, handler):
- elasticapm_client = app.get(CLIENT_KEY)
+ elasticapm_client = get_client()
  should_trace = elasticapm_client and not elasticapm_client.should_ignore_url(request.path)
  if should_trace:
- request[CLIENT_KEY] = elasticapm_client
  trace_parent = AioHttpTraceParent.from_headers(request.headers)
  elasticapm_client.begin_transaction("request", trace_parent=trace_parent)
  resource = request.match_info.route.resource

elasticapm/contrib/django/client.py

@@ -37,6 +37,7 @@
 from django.db import DatabaseError
 from django.http import HttpRequest
 
+from elasticapm import get_client as _get_client
 from elasticapm.base import Client
 from elasticapm.conf import constants
 from elasticapm.contrib.django.utils import iterate_with_template_sources
@@ -49,31 +50,26 @@
 
 
 default_client_class = "elasticapm.contrib.django.DjangoClient"
-_client = (None, None)
 
 
-def get_client(client=None):
+def get_client():
  """
  Get an ElasticAPM client.
 
  :param client:
  :return:
  :rtype: elasticapm.base.Client
  """
- global _client
-
- tmp_client = client is not None
- if not tmp_client:
- config = getattr(django_settings, "ELASTIC_APM", {})
- client = config.get("CLIENT", default_client_class)
-
- if _client[0] != client:
- client_class = import_string(client)
- instance = client_class()
- if not tmp_client:
- _client = (client, instance)
- return instance
- return _client[1]
+ if _get_client():
+ return _get_client()
+
+ config = getattr(django_settings, "ELASTIC_APM", {})
+ client = config.get("CLIENT", default_client_class)
+ client_class = import_string(client)
+ instance = client_class()
+ # `instance` will already be in elasticapm.base.CLIENT_SINGLETON due to the
+ # `__init__()` for Client
+ return instance
 
 
 class DjangoClient(Client):

elasticapm/contrib/flask/__init__.py

@@ -38,6 +38,7 @@
 
 import elasticapm
 import elasticapm.instrumentation.control
+from elasticapm import get_client
 from elasticapm.base import Client
 from elasticapm.conf import constants, setup_logging
 from elasticapm.contrib.flask.utils import get_data_from_request, get_data_from_response
@@ -50,17 +51,6 @@
 logger = get_logger("elasticapm.errors.client")
 
 
-def make_client(client_cls, app, **defaults):
- config = app.config.get("ELASTIC_APM", {})
-
- if "framework_name" not in defaults:
- defaults["framework_name"] = "flask"
- defaults["framework_version"] = getattr(flask, "__version__", "<0.7")
-
- client = client_cls(config, **defaults)
- return client
-
-
 class ElasticAPM(object):
  """
  Flask application for Elastic APM.
@@ -97,10 +87,18 @@ class ElasticAPM(object):
  def __init__(self, app=None, client=None, client_cls=Client, logging=False, **defaults):
  self.app = app
  self.logging = logging
- self.client_cls = client_cls
- self.client = client
+ self.client = client or get_client()
 
  if app:
+ if not self.client:
+ config = app.config.get("ELASTIC_APM", {})
+
+ if "framework_name" not in defaults:
+ defaults["framework_name"] = "flask"
+ defaults["framework_version"] = getattr(flask, "__version__", "<0.7")
+
+ self.client = client_cls(config, **defaults)
+
  self.init_app(app, **defaults)
 
  def handle_exception(self, *args, **kwargs):
@@ -125,8 +123,6 @@ def handle_exception(self, *args, **kwargs):
 
  def init_app(self, app, **defaults):
  self.app = app
- if not self.client:
- self.client = make_client(self.client_cls, app, **defaults)
 
  # 0 is a valid log level (NOTSET), so we need to check explicitly for it
  if self.logging or self.logging is logging.NOTSET:

elasticapm/contrib/opentracing/tracer.py

@@ -36,17 +36,15 @@
 from opentracing.tracer import Tracer as TracerBase
 
 import elasticapm
-from elasticapm import instrument, traces
+from elasticapm import get_client, instrument, traces
 from elasticapm.conf import constants
 from elasticapm.contrib.opentracing.span import OTSpan, OTSpanContext
 from elasticapm.utils import compat, disttracing
 
 
 class Tracer(TracerBase):
- _elasticapm_client_class = elasticapm.Client
-
  def __init__(self, client_instance=None, config=None, scope_manager=None):
- self._agent = client_instance or self._elasticapm_client_class(config=config)
+ self._agent = client_instance or get_client() or elasticapm.Client(config=config)
  if scope_manager and not isinstance(scope_manager, ThreadLocalScopeManager):
  warnings.warn(
  "Currently, the Elastic APM opentracing bridge only supports the ThreadLocalScopeManager. "

elasticapm/contrib/paste.py

@@ -29,10 +29,11 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 
+from elasticapm import get_client
 from elasticapm.base import Client
 from elasticapm.middleware import ElasticAPM
 
 
 def filter_factory(app, global_conf, **kwargs):
- client = Client(**kwargs)
+ client = get_client() or Client(**kwargs)
  return ElasticAPM(app, client)

elasticapm/contrib/pylons/__init__.py

@@ -29,6 +29,7 @@
 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 
 
+from elasticapm import get_client
 from elasticapm.base import Client
 from elasticapm.middleware import ElasticAPM as Middleware
 from elasticapm.utils import compat
@@ -44,5 +45,5 @@ def list_from_setting(config, setting):
 class ElasticAPM(Middleware):
  def __init__(self, app, config, client_cls=Client):
  client_config = {key[11:]: val for key, val in compat.iteritems(config) if key.startswith("elasticapm.")}
- client = client_cls(**client_config)
+ client = get_client() or client_cls(**client_config)
  super(ElasticAPM, self).__init__(app, client)