1. Create a service account for your GCP project as described here with the following roles (these roles could be more restrictive if required):

    1. Editor role.

    2. Kubernetes Engine Admin role.

    3. Container Registry Service Agent role.

    4. Storage Admin role.

    5. Storage Object Admin role.

  2. Generate a service account key for your service account as described here and export it as a JSON file.

  3. Export the GOOGLE_APPLICATION_CREDENTIALS variable and point it to the downloaded service account key from the previous step. For example: export GOOGLE_APPLICATION_CREDENTIALS=/home/ubuntu/.config/gcloud/sample-269400-9a41792a969b.json