accept_distributed_trace_headers (Python agent API)

Syntax

newrelic.agent.accept_distributed_trace_headers(headers, transport_type='HTTP')

This method is used for accepting the headers used to connect transactions within a distributed trace.

Requirements

Python agent version 5.6.0.135 or higher.

Distributed tracing must be enabled.

Description

For context on how to use this call, first read its partner API call insert_distributed_trace_headers and Enable distributed tracing with agent APIs.

This call is used to link transactions by parsing the distributed tracing headers generated by insert_distributed_trace_headers.

Parameters

Return values

When successful, returns True.

When unsuccessful, returns False. Accepting a payload can fail for several reasons:

• The current transaction is not enabled.
• Accept was called outside the scope of a transaction.
• The payload is empty.
• Distributed tracing is not enabled.
• accept_distributed_trace_* was called after a payload had been created and not before.
• accept_distributed_trace_* was called multiple times in a single transaction.
• The payload could not be parsed.
• The payload was sent from an untrusted account.

Examples

Accept a distributed trace payload inside a background task

An example of using accept_distributed_trace_headers in a background task:

@newrelic.agent.background_task()
def handle(request):
    newrelic.agent.accept_distributed_trace_headers(request.headers)

    _do_some_work()

Consume from a queue

An example of using accept_distributed_trace_headers and creating a background task for each message:

import newrelic.agent
newrelic.agent.initialize('newrelic.ini')
application = newrelic.agent.register_application(timeout=10.0)

def main(queue):
    for message in queue.consume():
        with newrelic.agent.BackgroundTask(application, 'Queue Consume'):
            newrelic.agent.accept_distributed_trace_headers(message.headers,
                    transport_type='Queue')
            _process_message(message)