Invalid stat name using opentelemetry

[alvaroserper]

Apache Airflow version

2.7.1

What happened

When running a dag an error ocurred. The error says that there is a metric with an invalid name. This causes that the task of the dag is set up for retry. Then the task executes again and is marked as success.

2023-10-10 13:05:21 [2023-10-10T11:05:21.738+0000] {local_executor.py:135} ERROR - Failed to execute task Invalid stat name: ***.dag.cwf_path_inspector_generator.delete-xcom-task.queued_duration.  Please see https://opentelemetry.io/docs/reference/specification/metrics/api/#instrument-name-syntax.
2023-10-10 13:05:21 Traceback (most recent call last):
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/executors/local_executor.py", line 131, in _execute_work_in_fork
2023-10-10 13:05:21     args.func(args)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/cli/cli_config.py", line 49, in command
2023-10-10 13:05:21     return func(*args, **kwargs)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/utils/cli.py", line 113, in wrapper
2023-10-10 13:05:21     return f(*args, **kwargs)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/cli/commands/task_command.py", line 430, in task_run
2023-10-10 13:05:21     task_return_code = _run_task_by_selected_method(args, _dag, ti)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/cli/commands/task_command.py", line 208, in _run_task_by_selected_method
2023-10-10 13:05:21     return _run_task_by_local_task_job(args, ti)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/cli/commands/task_command.py", line 270, in _run_task_by_local_task_job
2023-10-10 13:05:21     ret = run_job(job=job_runner.job, execute_callable=job_runner._execute)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/utils/session.py", line 77, in wrapper
2023-10-10 13:05:21     return func(*args, session=session, **kwargs)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/jobs/job.py", line 289, in run_job
2023-10-10 13:05:21     return execute_job(job, execute_callable=execute_callable)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/jobs/job.py", line 318, in execute_job
2023-10-10 13:05:21     ret = execute_callable()
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/jobs/local_task_job_runner.py", line 143, in _execute
2023-10-10 13:05:21     if not self.task_instance.check_and_change_state_before_execution(
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/utils/session.py", line 77, in wrapper
2023-10-10 13:05:21     return func(*args, session=session, **kwargs)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/models/taskinstance.py", line 1366, in check_and_change_state_before_execution
2023-10-10 13:05:21     self.emit_state_change_metric(TaskInstanceState.RUNNING)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/models/taskinstance.py", line 1450, in emit_state_change_metric
2023-10-10 13:05:21     Stats.timing(f"dag.{self.dag_id}.{self.task_id}.{metric_name}", timing)
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/metrics/otel_logger.py", line 266, in timing
2023-10-10 13:05:21     if self.metrics_validator.test(stat) and name_is_otel_safe(self.prefix, stat):
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/metrics/otel_logger.py", line 95, in name_is_otel_safe
2023-10-10 13:05:21     return bool(stat_name_otel_handler(prefix, name, max_length=OTEL_NAME_MAX_LENGTH))
2023-10-10 13:05:21   File "/usr/local/lib/python3.10/dist-packages/airflow/metrics/validators.py", line 142, in stat_name_otel_handler
2023-10-10 13:05:21     raise InvalidStatsNameException(
2023-10-10 13:05:21 airflow.exceptions.InvalidStatsNameException: Invalid stat name: ***.dag.cwf_path_inspector_generator.delete-xcom-task.queued_duration.  Please see https://opentelemetry.io/docs/reference/specification/metrics/api/#instrument-name-syntax

What you think should happen instead

There should not be an error with the name of a default metric causing a task to retry.

How to reproduce

Enable opentelemetry in airflow.cfg:

otel_on = True
otel_host = breeze-otel-collector
otel_port = 4318
otel_prefix = airflow
otel_interval_milliseconds = 30000  # The interval between exports, defaults to 60000
otel_ssl_active = False

Run opentelemetry collector docker:

otel-collector:
    image: otel/opentelemetry-collector-contrib:0.70.0
    container_name: "breeze-otel-collector"
    command: [--config=/etc/otel-collector-config.yml]
    volumes:
      - ./otel-collector/otel-collector-config.yml:/etc/otel-collector-config.yml
      # - ./otel-collector/keys:/etc/keys
    ports:
      - "24318:4318"    # OTLP http receiver
      - "28889:8889"    # Prometheus exporter metrics

Operating System

Ubuntu 22.04.3 LTS

Versions of Apache Airflow Providers

No response

Deployment

Docker-Compose

Deployment details

No response

Anything else

No response

Are you willing to submit PR?

• [ ] Yes I am willing to submit a PR!

Code of Conduct

• [X] I agree to follow this project's Code of Conduct

[boring-cyborg[bot]]

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[Bisk1]

looks like some legacy metric names weren't added to the exemptions list https://github.com/apache/airflow/pull/30873/files#diff-1cca954ec0be1aaf2c212e718c004cb0902a96ac60043bf0c97a782dee52cc32R55

@ferruzzi It looks like those metrics were added to the codebase shortly before the exemptions list was created: https://github.com/apache/airflow/blob/8fdf3582c2967161dd794f7efb53691d092f0ce6/airflow/models/taskinstance.py#L2184

should we add them to the exemption list?

    r"^dag\.(?P<dag_id>.*)\.(?P<task_id>.*)\.queued_duration$",
    r"^dag\.(?P<dag_id>.*)\.(?P<task_id>.*)\.scheduled_duration$",

or remove their invocations?

[alvaroserper]

Okey thank you, this will be solved in 3.0 v ?

[ferruzzi]

should we add them to the exemption list?

Must have been some awkward timing, adding new non-compliant names should have been prevented by the unit tests.... Yeah, I guess in this case, let's add it to the exemption list. Can you cut the PR?

It has already been fixed and will be applied in the next release https://github.com/apache/airflow/pull/34531

[ferruzzi]

I know this isn't really an answer, but the root cause id that when you combine a long dag_id and a long task_id, the total length of the metric name exceeds OTel's max name length. A temporary workaround would be to use shorter names. Again: I know that's not a satisfactory solution, and the fix has already been applied to the next release, but if you want a temporary band-aid, that's one option.

[ferruzzi]

I just double-checked and this fix should be in Airflow 2.7.2 which is currently being voted on and should be out Very Soon :tm: ((next week I think, but don't hold me to that))

[ferruzzi]

2.7.2 was released this morning!