Google Cloud Storage quota hit - how?

Question

When my app is trying to access files in a bucket using a SignedURL, a 429 response is received:

<Error>
    <Code>InsufficientQuota</Code>
    <Message>
        The App Engine application does not have enough quota.
    </Message>
    <Details>App s~[myappname] not have enough quota</Details>
</Error>

This error continues until the end of the day, when the quota is apparently reset, then I can use storage again. It's only a small app and does not have much usage. The project that contains the storage is set up to use billing. The files are being accessed from another project, which is also set up to use billing.

I'm not aware that Google Cloud Storage has any quotas that could be hit in this fashion. The only ones I know of are the ones here: https://cloud.google.com/storage/quotas but as far as I am aware, none of them apply.

• Buckets are not being created or destroyed.
• Updates are not being made to buckets.
• There are only a couple of IAM identities.
• There are no Pub/Sub notifications.
• Objects stored in the buckets are small. Is there any way I can find out why the quota is being exceeded?

Answer 1

It turns out it was because of a spending limit I had set on app engine. I didn't think those spending limits applied any more, but it turns out that's for new projects. Spending limits that have already been set on existing projects are effective, and I can personally attest that they do work!

Thanks for the comments @KevinQuinzel and @gso_gabriel.