Adding multiple hostNameBindings to a webapp

[tjerkmellink]

Version: Bicep CLI version v0.28.1.

Description: Adding multiple hostname bindings to webapp.
Detailed Message: "Cannot modify this site because another operation is in progress."

I have the following Bicep definition:

parameter file:

"appServicehostNames": {
	"value": [
	  {
		"name": "project-demo.test.domain.com",
		"thumbprint": "8BE826F779F48246ABCDEFFE6D7950A6C7"
	  },
	  {
		"name": "project-demo1.test.domain.com",
		"thumbprint": "8BE826F779F48246ABCDEFFE6D7950A6C7"
	  },
	  {
		"name": "project-demo2.test.domain.com",
		"thumbprint": "8BE826F779F48246ABCDEFFE6D7950A6C7"
	  },
	  {
		"name": "project-demo3.test.domain.com",
		"thumbprint": "8BE826F779F48246ABCDEFFE6D7950A6C7"
	  },
	  {
		"name": "project-demo4.test.domain.com",
		"thumbprint": "8BE826F779F48246ABCDEFFE6D7950A6C7"
	  }
	]
},

Main.bicep file

// AppService Custom hostnames
@description('Array of hostnames and their thumbprints.')
param appServicehostNames array = []

// AppService
resource appService 'Microsoft.Web/sites@2022-03-01' = {
  name: '${metadata.baseName}-${environmentType}'
  location: metadata.location
  dependsOn: [
    logAnalyticsWorkspace
  ]
  identity: {
    type: 'SystemAssigned'
  }
  tags: tags
}

// Hostname Bindings name
resource appServicehostNameBindings 'Microsoft.Web/sites/hostNameBindings@2021-02-01' = [for (hostName, index) in appServicehostNames: if(!empty(appServicehostNames)){
  name: '${metadata.baseName}-${environmentType}/${hostName.name}'
  kind: 'Microsoft.Web/sites/hostNameBindings'
  properties: {
    domainId: null
    siteName: appService.name
    hostNameType: 'Verified'
    sslState: 'SniEnabled'
    thumbprint: hostName.thumbprint
  }
}]

In this example we have 5 custom hostname bindings. When deploying this template the preview (what-if) works fine. However, when we deploy the code it fails with the above error. When using a single hostname binding it works.

The underlying problem is that the webapp cannot process multiple updates at the same time and would need some kind of 'DependOn' dependency.

Is there any guideline on how to deploy multiple hostname bindings to the same web app?

[czimbortibor]

Try the following https://learn.microsoft.com/en-us/azure/azure-resource-manager/bicep/loops#deploy-in-batches

@batchSize(1)
resource appServicehostNameBindings 'Microsoft.Web/sites/hostNameBindings@2021-02-01' = [for (hostName, index) in appServicehostNames: if(!empty(appServicehostNames)){
  ...
}]

[tjerkmellink]

Thank you so much! This did the job.