CDK python azure - LbBackendAddressPool Backend IP Configurations

Terraform CDK for Terraform
1

Hi everyone,

I am trying to generate Azure Loadbalancer Backend Pool Addresses, but I cannot seem to find the object to do that with.

I can see an LbBackendAddressPool object, but no direct way of adding any backend ip configuration settings. I do see a @builtins.property ‘backend_ip_configurations’, but no reference in init for the LbBackendAddressPool object, or a corresponding object.

Am I missing something, or do I need to use the escape hatch?

Kind regards,

Thomas Schockaert

2

I’m not familiar with the specific resources, but looking at the Terraform documentation, I’d expect there to be a LbBackendAddressPoolAddress type.

3

I’m thinking more in the direction of how the frontend_ip_configuration is done for the loadbalancer resource: you pass in a list of LbFrontEndIPConfiguration objects - that part does work.

I’d expect an LbBackendAddressPoolBackendIpConfigurations object because I can see the following object defined in the cdktf generated code for Azure: DataAzurermLbBackendAddressPoolBackendIpConfigurations.

The class DataAzurermLbBackendAddressPool references that one, but I’m as of yet unsure about the difference between the DataAzurerm* classes and their counterparts without the ‘DataAzurerm’ prefix.

For this: ‘DataAzurermLbBackendAddressPool’, there is an ‘LbBackendAddressPool’.
For this: ‘DataAzurermLbBackendAddressPoolBackendIpConfigurations’, there seems to be no ‘LbBackendAddressPoolBackendIpConfigurations’.

I don’t know if that’s a bug, or if I’m just not understanding certain things about how cdktf does its thing.

–
Thomas

4

I found some Azure documentation and it seems like backend ip configuration just works differently than for frontend.

A data source (DataAzurerm prefix) is basically just a way to look up data about existing infrastructure.

I can’t say for certain why the terminology for the returned backend address pool data is what it is, but the Azure api returns it that way, so Terraform exposes it.

5

Indeed, that seems to be the case: I should have a LbBackendAddressPoolAddress class in the generated init.py file, but it is not there.

I checked the provider version, and sure enough, apparently I was using an older version (2.0.0) - probably from the example on github. Once I set that to the latest version for azurerm, the object showed up.