How to implement OpenCensus to send custom dimensions to AI in Python?

With Python application, you can use OpenCensus to send the telemetry data. However, if your requirement is to use custom dimensions, you can use as below:

In case, your requirement is to use correlation ID with custom dimensions, Function App does not have the feature available yet. The team is working on a solution to light up this feature.

Until then, use the example below and initialize the OpenCensus component with the correlation id in your function’s trigger.

import json

import logging

import requests

import azure.functions as func

from opencensus.ext.azure.trace_exporter import AzureExporter

from opencensus.trace import config_integration

from opencensus.trace.samplers import ProbabilitySampler

from opencensus.trace.tracer import Tracer

from opencensus.trace import execution_context

from opencensus.trace.propagation.trace_context_http_header_format import TraceContextPropagator

config_integration.trace_integrations(['requests'])

exporter = AzureExporter(instrumentation_key="aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee")

def main(req: func.HttpRequest, context: func.Context) -> func.HttpResponse:

    ## these below four lines

    span_context = TraceContextPropagator().from_headers({"traceparent": context.trace_context.Traceparent, "tracestate": context.trace_context.Tracestate})

    tracer = Tracer(span_context=span_context, exporter=exporter, sampler=ProbabilitySampler(1.0))

    execution_context.set_opencensus_tracer(tracer)  # < -- sets the passed in tracer as the current tracer

    with tracer.span("parent"):

        response = requests.get(url='http://example.com')

    return json.dumps({

        'method': req.method,

        'ctx_func_name': context.function_name,

        'ctx_func_dir': context.function_directory,

        'ctx_invocation_id': context.invocation_id,

        'ctx_trace_context_Traceparent': context.trace_context.Traceparent,

        'ctx_trace_context_Tracestate': context.trace_context.Tracestate,

    })

Also, check the OpenCensus Azure extension Repository: https://github.com/census-instrumentation/opencensus-python/tree/master/contrib/opencensus-ext-azure#installation

Hope this helps!

Shashank Ranjan

Azure App Services Support Engineering