How do I set a cost limit in Google Developers Console

Solution 1:

You cannot. I asked Google about this, here's their response, from May 7 2016:

(GCE = Google cloud engine. No spending limits.
GAE = Google app engine — yes it has spending limits.)

... you are eligible for support on ... only ...
... [various helpful links] ...

That been said, at the moment there is no a feature that allows you to configure a limited budget on GCE. This feature is certainly available for GAE [1]. As you mentioned in your comments, you either can totally shut down your VMs (will depend on your use case) or set the VMs to send you alerts if they reach a certain traffic limit [2].

Sincerely,

Someone's first name
Technical Solutions Representative
Google Cloud Platform

[1] https://cloud.google.com/appengine/docs/quotas
[2] https://cloud.google.com/monitoring/support/notification-options

@wmdry, you wrote: "traffic to this link could explode" — I'm afraid of this too. That's why I asked Google about this. And I'm planning to avoid Google's CDN because of this, and use another CDN provider instead, which has spending limits. Because, unlike Nginx, I don't see any way for me to rate limit / throttle Google's CDN.

I do plan to use GCE (Google Cloud Engine) though. Therefore, right now I'm reading about how to rate limit my Nginx server. Because if I just configure Nginx correctly, then those $0.12 / GB you mentioned, cannot possible explode to ... like $10k in a month? What if Google sends a $10k bill when I'm back from an a few week's vacation, just because of my hobby project and a few people downloading a 1 MB movie over and over again forever (because: evil). Hmm, & the bigger & faster my servers, the higher the risk.

I hope Google will add spending limits, because I did want to use Google's CDN.

Update 2020: Apparently this does bite people from time to time — look here:
"Burnt $72k testing Firebase and Cloud Run and almost went bankrupt", Dec 08, 2020, https://news.ycombinator.com/item?id=25372336, In that case, they could contact Google and in the end didn't need to pay.

Solution 2:

As of July 2017 you can set budgets that send notifications via email but do not cap spending:

To set an alert-only budget, which will not cap spending:

1. Go to the Cloud Platform Console.
2. Open the console left side menu and click Billing
3. If you have more than one billing account, click the billing account name.
4. On the left, click Budgets & alerts.

Official help page: https://support.google.com/cloud/answer/6293540?hl=en

Solution 3:

I found that Google's documentation now provides two methods to actually limit the cost of a GCP project. It involves the following setup:

1. Create a Cloud Function that checks the cost against the budget, and carries out a certain action if the cost exceeds the budget. Google's Documentation provides a sample code snip that can either shutdown all VM instances in a Project or disable the billing for a project. Shutting down all VMs would stop all VM-related cost but you get to keep your data (and still have to pay for the storage). Disabling the billing for a project would effectively zap all cost-related activities and you could lose data. You can name the Cloud Function "budget-enforcer".
2. The Google code snip as provided above has a hard coded ZONE variable. Remember to change it to match your zone!
3. Create a Service Account to run the Cloud Function "budget-enforcer". For shutting down VMs, the Service Account would need role "Compute Instance Admin (v1)". For disabling billing on a project, the Service Account would need role "Project Billing Manager".
4. Set a Topic for the Cloud Function (I call mine "proj-name-stop-vm" and "proj-name-disable-bill").
5. Set up a budget alert as usual, and connect it to one of the Pub/Sub topic above.

Please be noted that Google's documentation did mention that there could be a delay between the cost exceeds a budget and the function is triggered, so you should build in a buffer if you have an absolute hard cost limit. I use 90% of the budget as the trigger line for shutting down my instances.