You can enable Cloud Trace for Go applications
by using OpenCensus. OpenCensus is
a set of instrumentation libraries for collecting trace and metric data that
work with multiple backends. For the latest details about OpenCensus
for Go, along with additional documentation and examples, see
opencensus-go
.
Installing the package
Retrieve the OpenCensus trace package:
go get -u go.opencensus.io/trace
Configuring the Stackdriver exporter
In order to export the collected Trace data, use a Stackdriver exporter:
If you are running on Google Cloud infrastructure, then
you don't need to set the ProjectID
field to your Google Cloud
project ID because the client library for Go automatically gathers
this data from a Google Cloud metadata server.
If you aren't running on Google Cloud infrastructure, then you must
set the ProjectID
field to your Google Cloud project ID. In the
example code, an environment variable is used and the application has been
modified to read this variable.
Configuring integration with Cloud Logging
For information on how to send Cloud Trace data to Cloud Logging, see Integrating with Cloud Logging.
Configuring your platform
You can use Cloud Trace on Google Cloud and other platforms.
Running on Google Cloud
When your application is running on Google Cloud, you don't need to provide authentication credentials in the form of a service account to the client library. However, you do need to ensure that your Google Cloud platform has the Cloud Trace API access scope enabled.
For the following configurations, the default access-scope settings enable the Cloud Trace API:
- App Engine flexible environment
App Engine standard environment
Google Kubernetes Engine (GKE)
Compute Engine
If you use custom access scopes, then you must ensure that
Cloud Trace API access scope
is enabled. For gcloud
users, specify access scopes using the --scopes
flag
and include the trace.append
Cloud Trace API access scope.
For example, to create a GKE cluster with only
the Cloud Trace API enabled, do the following:
gcloud container clusters create example-cluster-name --scopes=https://www.googleapis.com/auth/trace.append
Running locally and elsewhere
If your application is running outside of Google Cloud, then you must provide authentication credentials in the form of a service account to the client library. The service account must contain the Cloud Trace agent role. For instructions, see Creating a service account.
Google Cloud client libraries use
Application Default Credentials (ADC) to find your
application's credentials. You provide these credentials
by setting the GOOGLE_APPLICATION_CREDENTIALS
environment variable:
Linux/macOS
export GOOGLE_APPLICATION_CREDENTIALS=path-to-your-service-accounts-private-key
Windows
set GOOGLE_APPLICATION_CREDENTIALS=path-to-your-service-accounts-private-key
PowerShell:
$env:GOOGLE_APPLICATION_CREDENTIALS="path-to-your-service-accounts-private-key"
Sample Trace application for Go
Viewing the traces
After deployment, you can view the traces in the Cloud Console Trace Viewer.
Troubleshooting
For information on troubleshooting issues with Cloud Trace, go to the Troubleshooting page.
Resources
- OpenCensus
- GitHub:
census-instrumentation/opencensus-go
- Trace API V1 package
- Trace API V2 package
- Source code
- GitHub issue tracker
- Stack Overflow