cdumay-opentracing¶

cdumay-opentracing is a python library to facilitate opentracing integration.

Example¶

The following example shows how to use it with Jaeger:

import opentracing
from cdumay_opentracing import OpenTracingDriver, OpenTracingSpan


class A(object):
    "A sample class"
    def __init__(self):
        self.a = 5
        self.b = "toto"
        self.trace = dict()


class B(A):
    """A class which inherit of A"""


class DriverA(OpenTracingDriver):
    @classmethod
    def extract(cls, data):
        return opentracing.tracer.extract(cls.FORMAT, data.trace)

    @classmethod
    def inject(cls, span, data):
        opentracing.tracer.inject(span, cls.FORMAT, data.trace)

    @classmethod
    def tags(cls, data):
        return dict(a=data.a, b=data.b)


def child():
    """A function that automatically recovers the current span"""
    with OpenTracingSpan(B(), "test-2") as span:
        span.log_kv(dict(event="done"))


if __name__ == '__main__':
    import os, time
    from jaeger_client import Config
    from cdumay_opentracing import OpenTracingManager

    tracer = Config(service_name="test", config=dict(
        sampler=dict(type='const', param=1), logging=True,
        local_agent=dict(reporting_host=os.getenv('JAEGER_HOST', 'localhost'))
    )).initialize_tracer()

    OpenTracingManager.register(A, DriverA)

    a = A()
    with OpenTracingSpan(a, "test") as span:
        child()
        OpenTracingManager.log_kv(span, a, "done")

    time.sleep(4)
    tracer.close()

Explanations¶

line 5-14: We create classes for our example.
line 17-28: We create a driver which allows to automate the manipulation of the class A.
line 38-45: We initialize tracing
line 47: We register the driver into the Tracing manager. It will allow to manipulate A instances (and by extension B).
line 49-50: We make a span using a.
line 51: We call a function from a span which will create a sub-span.
line 54-55: We sleep and close to make sure that the span is sent.

Get It Now¶

Install the lib using pip:

pip install -U cdumay-opentracing

Features & API Focus¶

`OpenTracingManager` — The trace manager¶

class cdumay_opentracing.OpenTracingManager¶

This class manages the opentracing context.

It allows to recover using the opentracing library the initialized tracer.
It manage spans stack

classmethod register(clazz, driver)¶

Register a driver for the given class

Parameters:	clazz (Any) – Class managed by the driver. driver (cdumay_opentracing.OpenTracingDriver) – Driver to register.

classmethod get_driver(obj)¶

Find registered driver for the given object

Parameters:	obj (Any) – object to manipulate
Returns:	registered driver for this class
Return type:	cdumay_opentracing.OpenTracingDriver

classmethod tags(obj)¶

Extract tags from carrier object using a registered driver.

Parameters:	obj (Any) – object to manipulate
Returns:	Tags to add on span
Return type:	dict

classmethod get_current_span()¶

Get the current span

Returns:	The current span
Return type:	opentracing.span.Span or None

classmethod create_span(obj, name, tags)¶

Create a new span

Parameters:	obj (Any) – Any object name (str) – Span name tags (dict) – Additional tags
Returns:	Span
Return type:	opentracing.span.Span

classmethod finish_span(span)¶

Terminate the given span

Parameters:	span (opentracing.span.Span) – Span to finish

classmethod log_kv(span, obj, event, **kwargs)¶

Adds a log record to the Span.

Parameters:	span (opentracing.span.Span) – the Span instance to use. obj (Any) – the carrier object. event (str) – Span event name. kwargs (dict) – A dict of string keys and values of any type to log
Returns:	Returns the Span itself, for call chaining.
Return type:	opentracing.span.Span

`OpenTracingDriver` - Classes driver¶

class cdumay_opentracing.OpenTracingDriver¶

FORMAT¶: opentracing.Format used to load and store span context

classmethod extract(data)¶

Extract span context from a carrier object

Parameters:	data (Any) – the carrier object.
Returns:	a SpanContext instance extracted from carrier or None if no such span context could be found.

classmethod inject(span, data)¶

Injects the span context into a carrier object.

Parameters:	span (opentracing.span.SpanContext) – the SpanContext instance to inject data (Any) – the carrier object.

classmethod tags(data)¶

Extract tags from carrier object.

Parameters:	data (Any) – the carrier object.
Returns:	Tags to add on span
Return type:	dict

classmethod log_kv(span, data, event, **kwargs)¶