I can't find any documentation on how gcp scheduler works under the hood. An App Engine is needed in the project, so I assume that the Http calls or Pub/Sub messages are started from the App Engine. Currently I can use a cloud scheduler even without an App Engine in the project. Apparently a compute engine that also contains a permanently running VM is also sufficient. Could someone confirm my assumptions please or does anyone have sources on this?

CodePudding user response：

You might want to take a look into these official documents from Google regarding Using Pub/Sub to trigger a Cloud Functionand Cloud Scheduler Quickstart.

Here is another link to Firebase and schedule functions.

CodePudding user response：

I can't tell you how work Cloud Scheduler under the hood. I can just tell you that works well!

I'm sure there is a VM, or a cluster of VM, on Google serverless environment, and your Cloud Scheduler job is set on it. It's serverless, the under the hood doesn't matter, it works, and it's what I want!

Now, the relation with App Engine can be confusing. In fact, there is no longer relation between the product now, but you need the App Engine API activated on your project to use Cloud Scheduler. This strange things is normal if you have been using Google Cloud for a while. At the beginning, only App Engine existed, and Datastore, Cloud Task, Cloud Scheduler was all "modules" of App Engine. Years, after years, google has refactored and extracted these modules to create independent products, as you can see them today. However, some relations are still present, like the API activation.