ext-aiohttp-client implementation

This module is only supported on Python3.5, which is the oldest supported by
aiohttp.

docs/conf.py

@@ -65,6 +65,7 @@
         "https://opentracing-python.readthedocs.io/en/latest/",
         None,
     ),
+    "aiohttp": ("https://aiohttp.readthedocs.io/en/stable/", None),
 }
 
 # http://www.sphinx-doc.org/en/master/config.html#confval-nitpicky

docs/index.rst

@@ -33,6 +33,7 @@ and integration packages.
     :maxdepth: 1
     :caption: OpenTelemetry Integrations:
 
+    opentelemetry.ext.aiohttp_client
     opentelemetry.ext.flask
     opentelemetry.ext.http_requests
     opentelemetry.ext.jaeger

docs/opentelemetry.ext.aiohttp_client.rst

@@ -0,0 +1,10 @@
+opentelemetry.ext.aiohttp_client package
+========================================
+
+Module contents
+---------------
+
+.. automodule:: opentelemetry.ext.aiohttp_client
+    :members:
+    :undoc-members:
+    :show-inheritance:

ext/opentelemetry-ext-aiohttp-client/README.rst

@@ -0,0 +1,47 @@
+OpenTelemetry aiohttp client Integration
+========================================
+
+|pypi|
+
+.. |pypi| image:: https://badge.fury.io/py/opentelemetry-ext-aiohttp-client.svg
+   :target: https://pypi.org/project/opentelemetry-ext-aiohttp-client/
+
+This library allows tracing HTTP requests made by the
+`aiohttp client<https://docs.aiohttp.org/en/stable/client.html>`_ library.
+
+Installation
+------------
+
+::
+
+     pip install opentelemetry-ext-aiohttp-client
+
+Usage
+-----
+
+.. code-block:: python
+
+    import aiohttp
+    import asyncio
+
+    from opentelemetry.ext.aiohttp_client import create_trace_config
+
+    async def fetch(session, url):
+        async with session.get(url) as response:
+            return await response.text()
+
+    async def main():
+        async with aiohttp.ClientSession(trace_configs=[create_trace_config()]) as session:
+            html = await fetch(session, 'https://www.example.org')
+            print(html)
+
+    if __name__ == '__main__':
+        loop = asyncio.get_event_loop()
+        loop.run_until_complete(main())
+
+
+References
+----------
+
+* `OpenTelemetry Project <https://opentelemetry.io/>`_
+* `aiohttp client Tracing <https://docs.aiohttp.org/en/stable/tracing_reference.html>`_

ext/opentelemetry-ext-aiohttp-client/setup.cfg

@@ -0,0 +1,45 @@
+# Copyright 2020, OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+[metadata]
+name = opentelemetry-ext-aiohttp-client
+description = OpenTelemetry aiohttp client integration
+long_description = file: README.rst
+long_description_content_type = text/x-rst
+author = OpenTelemetry Authors
+author_email = cncf-opentelemetry-contributors@lists.cncf.io
+url = https://github.com/open-telemetry/opentelemetry-python/ext/opentelemetry-ext-aiohttp-client
+platforms = any
+license = Apache-2.0
+classifiers =
+    Development Status :: 3 - Alpha
+    Intended Audience :: Developers
+    License :: OSI Approved :: Apache Software License
+    Programming Language :: Python
+    Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+
+[options]
+python_requires = >=3.5.3
+package_dir=
+    =src
+packages=find_namespace:
+install_requires =
+    opentelemetry-api >= 0.5.dev0
+    aiohttp ~= 3.0
+
+[options.packages.find]
+where = src

ext/opentelemetry-ext-aiohttp-client/setup.py

@@ -0,0 +1,26 @@
+# Copyright 2020, OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import os
+
+import setuptools
+
+BASE_DIR = os.path.dirname(__file__)
+VERSION_FILENAME = os.path.join(
+    BASE_DIR, "src", "opentelemetry", "ext", "aiohttp_client", "version.py"
+)
+PACKAGE_INFO = {}
+with open(VERSION_FILENAME) as f:
+    exec(f.read(), PACKAGE_INFO)
+
+setuptools.setup(version=PACKAGE_INFO["__version__"])

ext/opentelemetry-ext-aiohttp-client/src/opentelemetry/ext/aiohttp_client/__init__.py

@@ -0,0 +1,211 @@
+# Copyright 2020, OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+The opentelemetry-ext-aiohttp-client package allows tracing HTTP requests
+made by the aiohttp client library.
+"""
+
+import contextlib
+import socket
+import types
+import typing
+
+import aiohttp
+
+from opentelemetry import propagators, trace
+from opentelemetry.ext.aiohttp_client.version import __version__
+from opentelemetry.trace import SpanKind
+from opentelemetry.trace.status import Status, StatusCanonicalCode
+
+
+# TODO: refactor this code to some common utility
+def http_status_to_canonical_code(status: int) -> StatusCanonicalCode:
+    # pylint:disable=too-many-branches,too-many-return-statements
+    if status < 100:
+        return StatusCanonicalCode.UNKNOWN
+    if status <= 399:
+        return StatusCanonicalCode.OK
+    if status <= 499:
+        if status == 401:  # HTTPStatus.UNAUTHORIZED:
+            return StatusCanonicalCode.UNAUTHENTICATED
+        if status == 403:  # HTTPStatus.FORBIDDEN:
+            return StatusCanonicalCode.PERMISSION_DENIED
+        if status == 404:  # HTTPStatus.NOT_FOUND:
+            return StatusCanonicalCode.NOT_FOUND
+        if status == 429:  # HTTPStatus.TOO_MANY_REQUESTS:
+            return StatusCanonicalCode.RESOURCE_EXHAUSTED
+        return StatusCanonicalCode.INVALID_ARGUMENT
+    if status <= 599:
+        if status == 501:  # HTTPStatus.NOT_IMPLEMENTED:
+            return StatusCanonicalCode.UNIMPLEMENTED
+        if status == 503:  # HTTPStatus.SERVICE_UNAVAILABLE:
+            return StatusCanonicalCode.UNAVAILABLE
+        if status == 504:  # HTTPStatus.GATEWAY_TIMEOUT:
+            return StatusCanonicalCode.DEADLINE_EXCEEDED
+        return StatusCanonicalCode.INTERNAL
+    return StatusCanonicalCode.UNKNOWN
+
+
+def url_path_span_name(params: aiohttp.TraceRequestStartParams) -> str:
+    """Extract a span name from the request URL path.
+
+    A simple `span_name` callable to extract the path portion of the
+    requested URL for use as the span name.
+
+    :param aiohttp.TraceRequestStartParams params: Parameters describing
+        the traced request.
+
+    :return: The URL path.
+    :rtype: str
+    """
+    return params.url.path
+
+
+def create_trace_config(
+    url_filter: typing.Optional[typing.Callable[[str], str]] = None,
+    span_name: typing.Optional[
+        typing.Union[
+            typing.Callable[[aiohttp.TraceRequestStartParams], str], str
+        ]
+    ] = None,
+) -> aiohttp.TraceConfig:
+    """Create an aiohttp-compatible trace configuration.
+
+    One span is created for the entire HTTP request, including intial
+    TCP/TLS setup if the connection doesn't exist.
+
+    By default the span name is set to the HTTP request method.
+
+    Example usage:
+
+    .. code-block:: python
+
+        import aiohttp
+        from opentelemetry.ext.aiohttp_client import create_trace_config
+
+        async with aiohttp.ClientSession(trace_configs=[create_trace_config()]) as session:
+            async with session.get(url) as response:
+                await response.text()
+
+
+    :param url_filter: A callback to process the requested URL prior to adding
+        it as a span attribute. This can be useful to remove sensitive data
+        such as API keys or user personal information.
+
+    :param str span_name: Override the default span name.
+
+    :return: An object suitable for use with :py:class:`aiohttp.ClientSession`.
+    :rtype: :py:class:`aiohttp.TraceConfig`
+    """
+    # `aiohttp.TraceRequestStartParams` resolves to `aiohttp.tracing.TraceRequestStartParams`
+    # which doesn't exist in the aiottp intersphinx inventory.
+    # Explicitly specify the type for the `span_name` param and rtype to work
+    # around this issue.
+
+    tracer = trace.tracer_provider().get_tracer(__name__, __version__)
+
+    async def on_request_start(
+        unused_session: aiohttp.ClientSession,
+        trace_config_ctx: types.SimpleNamespace,
+        params: aiohttp.TraceRequestStartParams,
+    ):
+        http_method = params.method.upper()
+        if trace_config_ctx.span_name is None:
+            request_span_name = http_method
+        elif callable(trace_config_ctx.span_name):
+            request_span_name = str(trace_config_ctx.span_name(params))
+        else:
+            request_span_name = str(trace_config_ctx.span_name)
+
+        trace_config_ctx.span = trace_config_ctx.tracer.start_span(
+            request_span_name,
+            kind=SpanKind.CLIENT,
+            attributes={
+                "component": "http",
+                "http.method": http_method,
+                "http.url": trace_config_ctx.url_filter(params.url)
+                if callable(trace_config_ctx.url_filter)
+                else str(params.url),
+            },
+        )
+
+        # Set the span as active via the `Tracer.use_span` context.
+        # TODO: would be nice to have an explicit API to set a context as active.
+        span_manager = contextlib.ExitStack()
+        span_manager.enter_context(
+            trace_config_ctx.tracer.use_span(
+                trace_config_ctx.span, end_on_exit=True
+            )
+        )
+        trace_config_ctx.span_manager = span_manager
+
+        propagators.inject(
+            tracer, type(params.headers).__setitem__, params.headers
+        )
+
+    async def on_request_end(
+        unused_session: aiohttp.ClientSession,
+        trace_config_ctx: types.SimpleNamespace,
+        params: aiohttp.TraceRequestEndParams,
+    ):
+        trace_config_ctx.span.set_status(
+            Status(http_status_to_canonical_code(int(params.response.status)))
+        )
+        trace_config_ctx.span.set_attribute(
+            "http.status_code", params.response.status
+        )
+        trace_config_ctx.span.set_attribute(
+            "http.status_text", params.response.reason
+        )
+        trace_config_ctx.span_manager.close()
+
+    async def on_request_exception(
+        unused_session: aiohttp.ClientSession,
+        trace_config_ctx: types.SimpleNamespace,
+        params: aiohttp.TraceRequestExceptionParams,
+    ):
+        if isinstance(
+            params.exception,
+            (aiohttp.ServerTimeoutError, aiohttp.TooManyRedirects),
+        ):
+            status = StatusCanonicalCode.DEADLINE_EXCEEDED
+        # Assume any getaddrinfo error is a DNS failure.
+        elif isinstance(
+            params.exception, aiohttp.ClientConnectorError
+        ) and isinstance(params.exception.os_error, socket.gaierror):
+            # DNS resolution failed
+            status = StatusCanonicalCode.UNKNOWN
+        else:
+            status = StatusCanonicalCode.UNAVAILABLE
+
+        trace_config_ctx.span.set_status(Status(status))
+        trace_config_ctx.span_manager.close()
+
+    def _trace_config_ctx_factory(**kwargs):
+        if kwargs.get("trace_request_ctx", None) is None:
+            kwargs["trace_request_ctx"] = {}
+        return types.SimpleNamespace(
+            span_name=span_name, tracer=tracer, url_filter=url_filter, **kwargs
+        )
+
+    trace_config = aiohttp.TraceConfig(
+        trace_config_ctx_factory=_trace_config_ctx_factory
+    )
+
+    trace_config.on_request_start.append(on_request_start)
+    trace_config.on_request_end.append(on_request_end)
+    trace_config.on_request_exception.append(on_request_exception)
+
+    return trace_config

ext/opentelemetry-ext-aiohttp-client/src/opentelemetry/ext/aiohttp_client/version.py

@@ -0,0 +1,15 @@
+# Copyright 2020, OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+__version__ = "0.5.dev0"