[2025-02-14] Manually patch scaling on App Engine service

patch_service_version.py

import json
import subprocess

import click
import requests

### https://cloud.google.com/appengine/docs/admin-api/reference/rest/v1beta/apps.services.versions/get
### https://cloud.google.com/appengine/docs/admin-api/reference/rest/v1beta/apps.services.versions/patch


def get_access_token():
    cmd = ("gcloud", "auth", "print-access-token")
    token = subprocess.check_output(cmd)
    return token.decode("ascii").strip()


@click.command()
@click.option("--project", "project", type=str, required=True)
@click.option("--service", "service", type=str, required=True)
@click.option("--version", "version", type=str, required=True)
@click.option("--min-total-instances", "min_total_instances", type=int, required=True)
@click.option("--max-total-instances", "max_total_instances", type=int, required=True)
def run_main(
    project: str,
    service: str,
    version: str,
    min_total_instances: int,
    max_total_instances: int,
):
    access_token = get_access_token()
    headers = {
        "X-Goog-User-Project": project,
        "Accept": "application/json",
        "Authorization": f"Bearer {access_token}",
    }

    url1 = f"https://appengine.googleapis.com/v1beta/apps/{project}/services/{service}/versions/{version}"
    url2 = f"https://appengine.googleapis.com/v1beta/apps/{project}/services/{service}/versions/{version}?updateMask=automatic_scaling.min_total_instances,automatic_scaling.max_total_instances"

    session = requests.Session()
    get_response = session.get(url1, headers=headers)
    if get_response.status_code != 200:
        raise RuntimeError("Wrong status for GET", get_response.status_code)

    version_body = get_response.json()
    version_body["automaticScaling"]["minTotalInstances"] = min_total_instances
    version_body["automaticScaling"]["maxTotalInstances"] = max_total_instances

    patch_response = session.patch(url2, json=version_body, headers=headers)
    print(patch_response)
    if patch_response.status_code == 200:
        return
    print(json.dumps(json.loads(patch_response.content), indent=2))


if __name__ == "__main__":
    run_main()