Is there plans to support nested loop on resources?

[Nik Grigoriadis (supernik)]

Resources like Application Gateway have more than one level of nesting and we have struggled to generalise our ARM templates to pass in configuration dynamically. In particular, the issues we've had were around the urlPathMaps and pathRules.

We have an external JSON file that describes the applications that need to be added to the AGW and we supply that file as a parameter to the AGW ARM template to generate all the required settings.

Is there any plans to support nested loops?

[Alex Frankel (alex-frankel)]

Yes, we do plan to support this. It's not possible to do nested loops of multiple properties within a resource in ARM templates today, so we will need to update the "runtime" to be able to handle that, and then we will enable it in bicep.

So first we will release general support for loops to get to parity with ARM templates, then add nested loops in a later release.

[Volodymyr Levchuk (vol-lev)]

Hi! Are there any updates or recommended workarounds? - I'm trying to deploy exactly same thing - Application Gateway with urlPathMaps / pathRules

[Ben Wilkinson (brwilkinson)]

HI Vlad Joanovic (@vladimirjoanovic)

Do you need a sub loop of path rules under your urlPathMaps ?

I don't think this covers that need, however take look ..
https://github.com/brwilkinson/AzureDeploymentFramework/blob/73df5f8f1dfc32415ca6d5051512edb7348a52b6/ADF/bicep/WAF-WAF.bicep#L55

However this is what I have been doing for this scenario, that I believe will cover your need:

I'll call into another module to generate the output variable that I need... then capture the output for the value.

https://github.com/brwilkinson/AzureDeploymentFramework/blob/dev/ADF/bicep/FD-frontDoor-BE.bicep

So this: calls the above:
https://github.com/brwilkinson/AzureDeploymentFramework/blob/73df5f8f1dfc32415ca6d5051512edb7348a52b6/ADF/bicep/FD-frontDoor.bicep#L76

module FDServiceBE 'FD-frontDoor-BE.bicep' = [for service in frontDoorInfo.services : {
  name: 'dp${Deployment}-AFD-BEDeploy-${frontDoorInfo.Name}-${service.Name}'
  params: {
    Deployment: Deployment
    AFDService: service
    Global: Global
  }
}]

Then on the backend I consume that output (notice the backends below):
https://github.com/brwilkinson/AzureDeploymentFramework/blob/73df5f8f1dfc32415ca6d5051512edb7348a52b6/ADF/bicep/FD-frontDoor.bicep#L124

resource FD 'Microsoft.Network/frontdoors@2020-05-01' = {
  name: '${Deployment}-afd${frontDoorInfo.name}'
  location: 'global'
  properties: {
    friendlyName: frontDoorInfo.name
    enabledState: 'Enabled'
    frontendEndpoints: frontendEndpoints
    healthProbeSettings: healthProbeSettings
    loadBalancingSettings: loadBalancingSettings
    routingRules: routingRules
    backendPoolsSettings: {
      enforceCertificateNameCheck: 'Enabled'
      sendRecvTimeoutSeconds: 30
    }
    backendPools: [for (service,index) in frontDoorInfo.services: {
      name: service.Name
      properties: {
        backends: FDServiceBE[index].outputs.backends
        loadBalancingSettings: {
          id: resourceId('Microsoft.Network/frontdoors/loadBalancingSettings', '${Deployment}-afd${frontDoorInfo.name}', service.LBSettings)
        }
        healthProbeSettings: {
          id: resourceId('Microsoft.Network/frontdoors/healthProbeSettings', '${Deployment}-afd${frontDoorInfo.name}', service.ProbeName)
        }
      }
    }]
  }
  dependsOn: [
    DNSCNAME
  ]
}

Also just to add, this is the input data... multiple frontdoors, then multiple services, then multiple backends per service. So I think that should map to your multiple urlPathMaps, with multiple pathRules.

https://github.com/brwilkinson/AzureDeploymentFramework/blob/2083f3021d86d9865453a1772e9dd7edc28734ec/ADF/tenants/AOA/azuredeploy.1.ACU1.T5.parameters.json#L730

          {
            "name": "02",
            "_afdverify": "AOA",
            "services": [
              {
                "Name": "GW01", // acu1-BRW-AOA-s1-afd 01 - apim01 .psthing.com
                "BEAddress": [
                  {
                    "address": "{Deployment}-api02.{Domain}",
                    "hostheader": "{Deployment}-api02.{Domain}",
                    "weight": 50
                  },

[dustinb222]

Is there an update on when nested loops in Bicep will be supported? Thanks!

[Alex Frankel (alex-frankel)]

No update. The work is being tracked in #2013

[Rune Gulbrandsen (dozer75)]

I added a workaround in the referenced issue, maybe that helps? Use the map function instead of for loops..