Viewing Airflow logs

This page describes how to access and view the Apache Airflow logs for Cloud Composer.

Log types

Cloud Composer includes the following Airflow logs:

  • Airflow logs: These logs are associated with single DAG tasks. You can view the task logs in the Cloud Storage logs folder associated with the Cloud Composer environment. You can also view the logs in the Airflow web interface.
  • Streaming logs: These logs are a superset of the logs in Airflow. To access streaming logs, use Stackdriver, use the Logs Viewer in the Google Cloud Console, or use Stackdriver Monitoring.

    You can also use logs-based metrics in Monitoring to set up alerting policies, for example to health check your Cloud Composer environment. Logging and Monitoring quotas apply. To learn about Stackdriver Logging and Stackdriver Monitoring for your Cloud Composer environment, see Monitoring environments in Stackdriver.

Logs in Cloud Storage

When you create an environment, Cloud Composer creates a Cloud Storage bucket and associates the bucket with your environment. Cloud Composer stores the logs for single DAG tasks in logs folder in the bucket. For the bucket name, see Determining the storage bucket name.

Log folder directory structure

The logs folder includes folders for each workflow that has run on the environment. Each workflow folder includes a folder for its DAGs and sub-DAGs. Each folder contains the log files for each task. The task filename indicates when the task started.

The following example shows the logs directory structure for an environment.

   |   │
   |   |   dag_1
   |   |   dag_2
   |   |   ...
       |   │
       |   └───task_1
       |   |   │   datefile_1
       |   |   │   datefile_2
       |   |   │   ...
       |   |
       |   └───task_2
       |       │   datefile_1
       |       │   datefile_2
       |       │   ...
           │   ...

Log retention

To prevent data loss, the logs saved in Cloud Storage remain in storage after you delete your environment. You must manually delete the logs from Cloud Storage.

Before you begin

The following permission is required to access Airflow logs in the Cloud Storage bucket for the Cloud Composer environment: storage.objectAdmin. For more information, see Cloud Composer Access control.

Viewing task logs in Cloud Storage

To view the log files for DAG tasks:

  1. To view log files, enter the following command, replacing the VARIABLES with appropriate values:

    gsutil ls -r gs://BUCKET/logs

  2. (Optional) To copy a single log or a subfolder, enter the following command, replacing the VARIABLES with appropriate values:


Viewing streaming logs in the Cloud Console

Cloud Composer produces the following logs:

  • airflow: The uncategorized logs that Airflow pods generate.
  • airflow-database-init-job: The logs Airflow database initialization job generates.
  • airflow-scheduler: The logs the Airflow scheduler generates.
  • airflow-webserver: The logs the Airflow web interface generates.
  • airflow-worker: The logs generated as part of workflow and DAG execution.
  • The logs Admin Activity generates.
  • composer-agent: The logs generated as part of create and update environment operations.
  • airflow-monitoring: The logs that Airflow monitoring generates.

To view the streaming log files:

  1. Go to the Stackdriver Logs Viewer in the Cloud Console.

  2. Select the logs you want to see.

    You can filter by properties such as log file and level, predefined label, task name, workflow, and execution date. For more information about selecting and filtering logs, see Viewing Logs.To learn about exporting logs, see Exporting with the Logs Viewer.

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