You can write logs to Logging from Python applications by using the Python logging handler included with the Logging client library, or by using Cloud Logging API Cloud client library for Python directly.
Before you begin
- Sign in to your Google Cloud account. If you're new to Google Cloud, create an account to evaluate how our products perform in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.
In the Google Cloud Console, on the project selector page, select or create a Google Cloud project.
Make sure that billing is enabled for your Cloud project. Learn how to confirm that billing is enabled for your project.
- Enable the Cloud Logging API.
- Prepare your environment for Python development.
Installing the library
To install the Cloud Logging library for Python, see Installing the client library.
Once installed, this library includes logging handlers to connect Python's standard logging module to Logging, as well as an API client library to access Cloud Logging manually.
Connecting the library to Python logging
To send all log entries to Cloud Logging by attaching the
Cloud Logging handler to the Python root logger, use the
# Imports the Cloud Logging client library import google.cloud.logging # Instantiates a client client = google.cloud.logging.Client() # Retrieves a Cloud Logging handler based on the environment # you're running in and integrates the handler with the # Python logging module. By default this captures all logs # at INFO level and higher client.get_default_handler() client.setup_logging()
Using the Python root logger
Once the handler is attached, any logs at, by default,
INFO level or higher
which are emitted in your application will be sent to Logging:
# Imports Python standard library logging import logging # The data to log text = "Hello, world!" # Emits the data using the standard logging module logging.warning(text)
If messages are logged to Logging from App Engine or
Google Kubernetes Engine, the handler will send them to those environments' respective
types; otherwise, logs will by default appear under the
python log in the
Global resource type.
Configuring the logging handler
To attach the Cloud Logging logging handler to only select Python loggers, or to otherwise configure the logging handler, go to the API library documentation.
Using the Cloud Client Library directly
For information on using the Cloud Logging Cloud client library for Python directly, see Cloud Logging Client Libraries.
Running on Google Cloud
The Cloud Logging library for Python can be used without needing to explicitly provide credentials.
Cloud Logging is automatically enabled for App Engine applications. No additional setup is required.
Google Kubernetes Engine (GKE)
If needed, you can also use the following command to add the
access scope when creating the cluster:
gcloud container clusters create example-cluster-name \ --scopes https://www.googleapis.com/auth/logging.write
When using Compute Engine VM instances, add the
access scope to each instance. When creating a new instance through the
Google Cloud Console, you can do this in the Identity and API access section
of the Create Instance panel. Use the Compute Engine default service
account or another service account of your choice, and select
Allow full access to all Cloud APIs in the Identity and API access
section. Whichever service
account you select, ensure that it has been granted the
Logs Writer role in the IAM & Admin section of the
Running locally and elsewhere
To use the Cloud Logging library for Python outside of Google Cloud, including running the library on your own workstation, on your data center's computers, or on the VM instances of another cloud provider, you must supply your Google Cloud project ID and appropriate service account credentials directly to the Cloud Logging library for Python.
You can create and obtain service account credentials manually. When specifying the Role field, use the Logs Writer role. For more information on Identity and Access Management roles, go to Access control guide.
Viewing the logs
After deployment, you can view the logs in the Logs Explorer.
In the Logs Explorer, you must specify one or more resources, but the resource selection might not be obvious. Here are some tips to help you get started:
If you are deploying your application to App Engine or using the App Engine-specific libraries, set your resource to GAE Application.
If you are deploying your application on Compute Engine, set the resource to GCE VM Instance.
If you are deploying your application on Google Kubernetes Engine, your cluster's logging configuration determines the resource type of the log entries. For a detailed discussion on the Legacy Google Cloud's operations suite and the Google Cloud's operations suite Kubernetes Monitoring solutions, and how those options affect the resource type, see Migrating to Google Cloud's operations suite Kubernetes Monitoring.
If your application is using the Cloud Logging API directly, the resource is dependent on the API and your configuration. For example, in your application, you can specify a resource or use a default resource.
If you don't see any logs in the Logs Explorer, to see all log entries, switch to the advanced query mode and use an empty query.
- To switch to the advanced query mode, click menu (▾) at the top of the Logs Explorer and then select Convert to advanced filter.
- Clear the content that appears in the filter box.
- Click Submit Filter.
You can examine the individual entries to identify your resources.