docs: update running system tests instructions
@@ -401,9 +401,11 @@ resource names that incorporate aspects of your test, such as `tc.ProjectID +
## Running system tests
+1. To run the system test yourself, you need a Google Cloud Project and a service account. During the creation of the service account, you should download the JSON credential file.
+1. Ensure the IAM roles needed by the tests are added to the service account.
+1. Ensure you are logged in using `gcloud auth login`.
1. Set the `GOLANG_SAMPLES_PROJECT_ID` environment variable to a suitable test project.
-1. Ensure you are logged in using `gcloud auth login` or set the `GOOGLE_APPLICATION_CREDENTIALS` environment variable to the path of your credentials file.
- Tests are authenticated using [Application Default Credentials](https://developers.google.com/identity/protocols/application-default-credentials).
+1. Set the `GOOGLE_APPLICATION_CREDENTIALS` environment variable to the credential file path. Tests are authenticated using [Application Default Credentials](https://developers.google.com/identity/protocols/application-default-credentials).
1. Install the test dependencies:
`go get -t -d github.com/GoogleCloudPlatform/golang-samples/...`
