Extract nested json value via variable

[derekleegh]

Hi,

I have a unique use case here if I can get your advice on what is the best approach.

Based on your example on README.md, I would like to extract the db and get the value as a json.

value = {"password": "bar"}

It works with your jsondecode(data.sops_file.demo-secret.raw).db

How can i pass the .db as an variable?

What i want to achieve is something like this: jsondecode(data.sops_file.demo-secret.raw)[var.key] where var.key is '.db'

The idea is that the key we want to extract can be a variable without hardcoding the .db

Hope you can help me with this use case.

Thanks

[carlpett]

Hi @derekleegh,
That was indeed quite a new case. I'm actually not certain if it is possible to do this? This would be limited by HCL rather than the provider. So you might need to look at a workaround if we cannot figure out how to redefine the problem, so to speak. Do you have very large files, or need to loop over them, or how did the use-case come about?

[derekleegh]

@carlpett thanks for coming back to me.

This use case comes from our org where we want to store a json block in parameter store rather than just single value. So as an example, we have the following secrets.json

{
	"Backend": {
		"Server": {
			"Port": 8080
		},
		"Database": {
			"WriteCredentials": {
				"Endpoint": "xxx",
				"Username": "readwrite-user",
				"Password": "xx",
				"Port": 5432,
				"Database": "db"
			}
		}
	}
}

We want to extract the Database section and store it as a single parameter store value.

Workaround for now is we can achieve this by doing jsondecode(data.sops_file.demo-secret.raw).Backend.Database by using the raw data.

However, in terraform we would like the Backend.Database value to be a variable so we can be like jsondecode(data.sops_file.demo-secret.raw).${var.secret_position} where var.secret_position="Backend.Database" something like that.

This will gives us flexibility of extracting the secrets using for_loop.

Alternatively via the map values where data.sops_file.demo-secret.data["${var.secret_position}"] like this.

[nobbs]

Hey @derekleegh.

Have you tried the lookup function?

Something like

lookup(jsondecode(data.sops_file.demo-secret.raw), var.secret_position, {})

should work.