Managed Service for OpenTelemetry:Use Jaeger to report the trace data of a Python application

Usage notes

• For Python, Jaeger v1.25 allows you to report trace data only by using the Jaeger agent. You cannot report trace data over HTTP. For more information, see Client Library Features in official Jaeger documentation.

• For Python, Jaeger v1.25 allows you to report trace data from the Jaeger client to the Jaeger agent only over UDP. The UDP protocol does not guarantee the reliability of communication. To ensure reliable transfer of trace data, we recommend that you run the Jaeger client and Jaeger agent on the same host.

Step 1: Build environments

In this example, the following versions for Docker, the Jaeger agent, the Jaeger client, and Python are required to build environments.

Docker and the Jaeger agent

Docker version: 20.10.7

Jaeger agent version: 1.25

1. Run the following command in Docker Hub to pull the image of the Jaeger agent v1.25:

   docker pull jaegertracing/jaeger-agent:1.25

2. Run the following command to run the Jaeger agent v1.25:

   docker run -d --name jaeger-agent  -p 5775:5775/udp -p 6831:6831/udp -p 6832:6832/udp -p 5778:5778/tcp jaegertracing/jaeger-agent:1.25 --reporter.type=grpc --reporter.grpc.host-port=<endpoint>(Enter the endpoint) --agent.tags=<auth>(Enter the authentication information)

   Note

   Replace <endpoint> and <auth> with the endpoint and authentication information displayed on the Cluster Configurations page of the Managed Service for OpenTelemetry console. For more information about how to obtain the endpoint, see the "Prerequisites" section of this topic.

Python and the Jaeger client

Python version: 3.8.5

Jaeger client version: 4.6.0

Install the following Python package in Python to configure the Jaeger client environment:

certifi==2021.5.30
charset-normalizer==2.0.4
idna==3.2
jaeger-client==4.6.0
opentracing==2.4.0
requests==2.26.0
six==1.16.0
threadloop==1.0.2
thrift==0.13.0
tornado==6.1
urllib3==1.26.6

Step 2: Create a Tracer object

1. Create a Python file that contains the following content.

   Run the following code to create a Tracer object and use the Tracer object to create a span to report data to the Managed Service for OpenTelemetry backend:

   import logging
   import time
   from jaeger_client import Config
   
   
   def construct_span(tracer):
       with tracer.start_span('AliyunTestSpan') as span:
           span.log_kv({'event': 'test message', 'life': 42})
           print("tracer.tages: ", tracer.tags)
           with tracer.start_span('AliyunTestChildSpan', child_of=span) as child_span:
               span.log_kv({'event': 'down below'})
           return span
   
   
   if __name__ == "__main__":
       log_level = logging.DEBUG
       logging.getLogger('').handlers = []
       logging.basicConfig(format='%(asctime)s %(message)s', level=log_level)
   
       config = Config(
           config={ # usually read from some yaml config
               'sampler': {
                   'type': 'const',
                   'param': 1,
               },
               'local_agent': {
                   # Specify the hostname and port number of the Jaeger agent. 
                   # To ensure data reliability, we recommend that you run the Jaeger client and the Jaeger agent on the same host. Therefore, the reporting_host parameter is set to 127.0.0.1. 
                   'reporting_host': '127.0.0.1',
                   'reporting_port': 6831,
               },
               'logging': True,
           },
           # Specify the application name.
           service_name="mytest3",
           validate=True
       )
   
       # this call also sets opentracing.tracer
       tracer = config.initialize_tracer()
   
       span = construct_span(tracer)
   
       time.sleep(2)   # yield to IOLoop to flush the spans - https://github.com/jaegertracing/jaeger-client-python/issues/50
       tracer.close()  # flush any buffered spans

2. Execute the Python file.

View data in the Managed Service for OpenTelemetry console

1. Log on to the Managed Service for OpenTelemetry console. In the left-side navigation pane, click Applications.

2. On the Applications page, select a region in the top navigation bar and click the name of the application.

3. In the Application Overview section, you can view the key performance metrics and topology of the application.

   

4. In the left-side navigation pane, click Application Details.

   On the Overview tab of the Application Details section, you can view the application overview.

5. In the Application Details section, click the Traces tab.

   On the Traces tab, you can view the traces of the application.

Use Jaeger

This section provides common methods for using Jaeger. For more information, see Getting Started in official Jaeger documentation.

• Create a Tracer object:

  from jaeger_client import Config
  
  def init_jaeger_tracer(service_name='your-app-name'):
      config = Config(config={}, service_name=service_name)
      return config.initialize_tracer()

• Create and finish a span:

  // Start a span that does not have a parent span. 
  tracer.start_span('TestSpan') 
  # Start a span that has a parent span. 
  tracer.start_span('ChildSpan', child_of=span)
  # Finish the span. 
   span.finish()

• Pass a SpanContext:

  // Serialization: Inject a SpanContext and pass it to the next span. 
  tracer.inject(
          span_context=span.context, format=Format.TEXT_MAP, carrier=carrier
      )
  # Deserialization: Extract a SpanContext that is passed. 
  span_ctx = tracer.extract(format=Format.TEXT_MAP, carrier={})