CODEWITHSUNDEEP
google-cloud-platformgoogle-cloud-functionsworkflowgoogle-cloud-pubsub
Alessandro Aguilar
Alessandro Aguilar

Reputation: 401

GCP Best way to manage multiple cloud function flow

I'm studying GCP and reading about different ways to communicate and manage cloud functions I end up wondering when to use each of the services that offer GCP.

So, I have been reading about GCP Composer, GCP Workflows, Cloud Pub/Sub and I don't see clearly when to use each one, or use simple HTTP calls.

I understand that it depends a lot on the application that you are building, but for example, If I'm building a payment gateway and some functions should be fired after the payment was verified, like sending emails, making not related business logic, adding the purchase to a sales platform. So which one should be the way I manage this flow and in which case would be better to use the others? Should I use events to create an async flow with Pub/Sub, or use complex solutions like composer and workflows? or just simple HTTP calls?

Upvotes: 0

Views: 418

Answers (1)

guillaume blaquiere
guillaume blaquiere

Reputation: 75735

As always, it depends!! Even in your use case, it depends! Ok, after a payment you want to send an email, make business logic, adding the order to your databases,...

But, is all theses actions can be done in parallel, or you need to execute them in a certain order and if a step fails, you stop the process?

In the first case, you can use Cloud PubSub with 1 message published (payment OK) and then a fan out to several functions in parallel. Else, you can use workflow to test the response of the fonction and then to call, or not the following fonctions. With composer you can perform much more checks and actions.

You can also imagine to send another email 24h after to thank the customer for their order, and use Cloud Task to delayed an action.

You talked about Cloud Functions, but you also have other solutions to host code on GCP: App Engine and Cloud Run. Cloud function is, most of the time, single purpose. Sending an email is perfect for a function.

Now, if you have "set of functions" to browse your stock, view the object details, review the price, and book an object (validate an order "books" the order content in your warehouse), the "functions" are all single purpose but related to the same domain: warehouse management. Thus you can create a webserver that propose different path to manage the warehouse (a microservice for the warehouse if you prefer) and host it on CloudRun or App Engine.

Each product has its strength and weakness. You will also see this when you will learn about the storage on GCP. Most of the time, you can achieve things with several product, but if you don't use the right one, it will be slower, or cost much more.

Upvotes: 3

Related Questions