OpenTelemetry Starlette Instrumentation
This library provides automatic and manual instrumentation of Starlette web frameworks, instrumenting http requests served by applications utilizing the framework.
auto-instrumentation using the opentelemetry-instrumentation package is also supported.
Installation
pip install opentelemetry-instrumentation-starlette
References
API
Usage
from opentelemetry.instrumentation.starlette import StarletteInstrumentor
from starlette import applications
from starlette.responses import PlainTextResponse
from starlette.routing import Route
def home(request):
return PlainTextResponse("hi")
app = applications.Starlette(
routes=[Route("/foobar", home)]
)
StarletteInstrumentor.instrument_app(app)
Configuration
Exclude lists
To exclude certain URLs from tracking, set the environment variable OTEL_PYTHON_STARLETTE_EXCLUDED_URLS
(or OTEL_PYTHON_EXCLUDED_URLS
to cover all instrumentations) to a string of comma delimited regexes that match the
URLs.
For example,
export OTEL_PYTHON_STARLETTE_EXCLUDED_URLS="client/.*/info,healthcheck"
will exclude requests such as https://site/client/123/info
and https://site/xyz/healthcheck
.
Request/Response hooks
This instrumentation supports request and response hooks. These are functions that get called right after a span is created for a request and right before the span is finished for the response.
The server request hook is passed a server span and ASGI scope object for every incoming request.
The client request hook is called with the internal span, and ASGI scope and event when the method
receive
is called.The client response hook is called with the internal span, and ASGI scope and event when the method
send
is called.
For example,
def server_request_hook(span: Span, scope: dict[str, Any]):
if span and span.is_recording():
span.set_attribute("custom_user_attribute_from_request_hook", "some-value")
def client_request_hook(span: Span, scope: dict[str, Any], message: dict[str, Any]):
if span and span.is_recording():
span.set_attribute("custom_user_attribute_from_client_request_hook", "some-value")
def client_response_hook(span: Span, scope: dict[str, Any], message: dict[str, Any]):
if span and span.is_recording():
span.set_attribute("custom_user_attribute_from_response_hook", "some-value")
StarletteInstrumentor().instrument(server_request_hook=server_request_hook, client_request_hook=client_request_hook, client_response_hook=client_response_hook)
Capture HTTP request and response headers
You can configure the agent to capture specified HTTP headers as span attributes, according to the semantic convention.
Request headers
To capture HTTP request headers as span attributes, set the environment variable
OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST
to a comma delimited list of HTTP header names.
For example,
export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST="content-type,custom_request_header"
will extract content-type
and custom_request_header
from the request headers and add them as span attributes.
Request header names in Starlette are case-insensitive. So, giving the header name as CUStom-Header
in the
environment variable will capture the header named custom-header
.
Regular expressions may also be used to match multiple headers that correspond to the given pattern. For example:
export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST="Accept.*,X-.*"
Would match all request headers that start with Accept
and X-
.
Additionally, the special keyword all
can be used to capture all request headers.
export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST="all"
The name of the added span attribute will follow the format http.request.header.<header_name>
where <header_name>
is the normalized HTTP header name (lowercase, with -
replaced by _
). The value of the attribute will be a
list containing the header values.
For example:
http.request.header.custom_request_header = ["<value1>", "<value2>"]
Response headers
To capture HTTP response headers as span attributes, set the environment variable
OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_RESPONSE
to a comma delimited list of HTTP header names.
For example,
export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_RESPONSE="content-type,custom_response_header"
will extract content-type
and custom_response_header
from the response headers and add them as span attributes.
Response header names in Starlette are case-insensitive. So, giving the header name as CUStom-Header
in the
environment variable will capture the header named custom-header
.
Regular expressions may also be used to match multiple headers that correspond to the given pattern. For example:
export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_RESPONSE="Content.*,X-.*"
Would match all response headers that start with Content
and X-
.
Additionally, the special keyword all
can be used to capture all response headers.
export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_RESPONSE="all"
The name of the added span attribute will follow the format http.response.header.<header_name>
where <header_name>
is the normalized HTTP header name (lowercase, with -
replaced by _
). The value of the attribute will be a
list containing the header values.
For example:
http.response.header.custom_response_header = ["<value1>", "<value2>"]
Sanitizing headers
In order to prevent storing sensitive data such as personally identifiable information (PII), session keys, passwords,
etc, set the environment variable OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SANITIZE_FIELDS
to a comma delimited list of HTTP header names to be sanitized. Regexes may be used, and all header names will be
matched in a case-insensitive manner.
For example,
export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SANITIZE_FIELDS=".*session.*,set-cookie"
will replace the value of headers such as session-id
and set-cookie
with [REDACTED]
in the span.
Note
The environment variable names used to capture HTTP headers are still experimental, and thus are subject to change.
API
- class opentelemetry.instrumentation.starlette.StarletteInstrumentor(*args, **kwargs)[source]
Bases:
BaseInstrumentor
An instrumentor for starlette
See BaseInstrumentor
- static instrument_app(app, server_request_hook=None, client_request_hook=None, client_response_hook=None, meter_provider=None, tracer_provider=None)[source]
Instrument an uninstrumented Starlette application.
- instrumentation_dependencies()[source]
Return a list of python packages with versions that the will be instrumented.
The format should be the same as used in requirements.txt or pyproject.toml.
For example, if an instrumentation instruments requests 1.x, this method should look like: :rtype:
Collection
[str
]- def instrumentation_dependencies(self) -> Collection[str]:
return [‘requests ~= 1.0’]
This will ensure that the instrumentation will only be used when the specified library is present in the environment.