net-lb*-int - backends[].balancing mode - review possibile values

[wiktorn]

Found in modules/net-lb-int when applying end-to-end example, but this may affect also other Load Balancer modules:

Error creating RegionBackendService: googleapi: Error 400: Invalid value for field 'resource.backends[0].balancingMode': 'UTILIZATION'. Balancing mode must be CONNECTION for an INTERNAL backend service., invalid

Cross checked with docs and analysis for each of the module below.

net-lb-int

This are allowed values (according to docs) for Internal passthrough Network Load Balancer

• fix examples and validation rule (Remove incompatible balancing_mode #1769)
• change defaults where current default value is not usable?
• remove variable if only one value is possibile?

net-lb-ext

Only CONNECTION allowed per docs, but no changes necessary as this attribute is not controlled by module inputs.

• Small update in the doc string to clean up UTILIZATION

net-lb-proxy-int

OK

net-lb-app-int

OK. Can add vallidation:

  validation {
    condition = alltrue([
      for b in var.backend_service_config.backends : contains(
        ["RATE", "UTILIZATION"], coalesce(b.balancing_mode, "UTILIZATION")
    )])
    error_message = "When specified balancing mode needs to be 'RATE' or 'UTILIZATION'."
  }

net-lb-app-ext

OK. Can add vallidation:

  validation {
    condition = alltrue([
      for b in var.backend_service_config.backends : contains(
        ["RATE", "UTILIZATION"], coalesce(b.balancing_mode, "UTILIZATION")
    )])
    error_message = "When specified balancing mode needs to be 'RATE' or 'UTILIZATION'."
  }

[ludoo]

It's not a module-level but a blueprint problem. :)

[ludoo]

defaults are correct for each load balancer type, and need to be changed in blueprints to suit specific backends