Switching gcloud accounts for Terraform and Kubernetes - kubernetes

Question

I have two emails associated with two separate gcloud projects.
I can easily switch the projects with:
$ gcloud auth list
Credentialed Accounts
ACTIVE ACCOUNT
first#project1
* second#project2
$ gcloud config set account first#project1
I can then see, that gcloud did change the active account. I can also do this with:
$ gcloud config configurations list
...
$ gcloud config configurations set project1
And I can see the active configuration changes.
However it does not seem to have any effect for kubectl and terraform commands as they still use the previous configuration.
What am i doing wrong? How should I switch between the projects? It seems it has something to do with application-default account, but that looks it cannot be easily switched without relogin?
Edit: to precise the question:
What would be a correct sequence of commands to switch between gcloud auths (eg. first#project1, second#project2) so that it is usable in Kubernetes, Terraform and others?

Answer 1

Kubectl and terraform have own config or we can say context
for kubectl you need to change the cluster config using
kubectl config get-contexts
kubectl config use-context <cluster-name>
Or else each time you have set the context of Kubernetes cluster using Gcloud and it will get auto changed for kubectl
gcloud container clusters get-credentials cluster-name which takes the --project also.
Read more at : https://cloud.google.com/kubernetes-engine/docs/how-to/cluster-access-for-kubectl
For changing project in terraform there are different ways
Using different serviceaccount keys JSON
Changing project config inside terraform provider
Setting up environment variable GOOGLE_APPLICATION_CREDENTIALS
setting project inside the Provider
provider "google" {
project = "my-project-id"
region = "us-central1"
zone = "us-central1-c"
}
https://registry.terraform.io/providers/hashicorp/google/latest/docs/guides/provider_reference
Best approach to use : https://registry.terraform.io/providers/hashicorp/google/latest/docs/guides/provider_reference#credentials-1
As you are writing IAC so all config in code.
List of all possible methods for authentication terraform:
https://registry.terraform.io/providers/hashicorp/google/latest/docs/guides/provider_reference#authentication

Answer 2

SDK provides the following command, this helps in applying credentials to all API calls that make use of the Application Default Credentials client library.
Terraform is one of the classic applications that have this dependency.
gcloud auth application-default login
Here is the documentation for the above command.