Domeneshop DNS Script for Azure Bicep Deployment with App Service

domeneshop-dns-setup.bicep

param targetDomain string
param appName string
param customDomainVerificationId string

@secure()
param domainUsername string
@secure()
param domainPassword string

resource ds 'Microsoft.Resources/deploymentScripts@2023-08-01' = {
  kind: 'AzurePowerShell'
  name: 'domeneshop-dns-${targetDomain}'
  location: resourceGroup().location
  properties: {
    azPowerShellVersion: '10.4'
    retentionInterval: 'PT1H'
    timeout: 'PT5M'
    cleanupPreference: 'OnSuccess'
    arguments: '-appname ${appName} -customDomainVerificationId ${customDomainVerificationId} -targetDomain ${targetDomain}'
    environmentVariables: [
      { name: 'DOMAIN_USERNAME', secureValue: domainUsername } 
      { name: 'DOMAIN_PASSWORD', secureValue: domainPassword }
    ]
    scriptContent: '''
param([string] $appname, [string] $customDomainVerificationId, [string] $targetDomain)

$zone = $targetDomain.Split(".")[-2..-1] -join "."
$domainHost = $targetDomain.Split(".")[0..($targetDomain.Split(".").Length - 3)] -join "."

$isRoot = $false

if ($domainHost -eq "" -or $domainHost -eq $targetDomain) {
    # If the domain is a root domain (e.g., example.com), set the host to "@" and mark it as root
    $domainHost = "@"
    $isRoot = $true
}

$auth = "Basic " + [Convert]::ToBase64String([Text.Encoding]::ASCII.GetBytes("${Env:DOMAIN_USERNAME}:${Env:DOMAIN_PASSWORD}"))

$domains = Invoke-WebRequest -Uri "https://api.domeneshop.no/v0/domains?domain=$zone" -Method Get `
    -Headers @{Authorization = $auth}

$domainId = (ConvertFrom-Json -InputObject $domains.Content)[0].id

Write-Output "Domain Content: $($domains.Content)"
Write-Output "Domain ID: $domainId"
Write-Output "DomainHost: $domainHost"

# Check if the TXT record already exists for the custom domain verification ID
$existingTxtRecord = Invoke-WebRequest -Uri "https://api.domeneshop.no/v0/domains/$domainId/dns?host=asuid.$($appname)&type=TXT" -Method Get `
    -Headers @{Authorization = $auth} `
    -ContentType "application/json"

$existingTxtList = (ConvertFrom-Json -InputObject $existingTxtRecord.Content)
if ($existingTxtList.Count -gt 0) {
    Write-Output "TXT record already exists for asuid.$($appname)."
    Write-Output "Existing TXT Record: $($existingTxtList | ConvertTo-Json)"
    if($existingTxtList[0].data -eq $customDomainVerificationId) {
        Write-Output "The existing TXT record matches the custom domain verification ID."
    } else {
        Write-Error "The existing TXT record does not match the custom domain verification ID. "
        exit -1
    }
} else {
    Write-Output "No existing TXT record found for asuid.$($appname)."
    $txtRecord = Invoke-WebRequest -Uri "https://api.domeneshop.no/v0/domains/$domainId/dns" -Method Post `
        -Headers @{Authorization = $auth} `
        -ContentType "application/json" `
        -Body (@{
    host = "asuid.$($appname)"
    ttl = 3600
    type = "TXT"
    data = $customDomainVerificationId
    } | ConvertTo-Json)

    Write-Output "TXT Record Response: $($txtRecord.Content)"
}

$existingCnameRecord = Invoke-WebRequest -Uri "https://api.domeneshop.no/v0/domains/$domainId/dns?host=$domainHost&type=$($isRoot ? 'ANAME' : 'CNAME')" -Method Get `
    -Headers     @{Authorization = $auth} `
    -ContentType "application/json"

$existingCnameList = (ConvertFrom-Json -InputObject $existingCnameRecord.Content)
if ($existingCnameList.Count -gt 0) {
    Write-Output "CNAME record already exists for $domainHost."
    Write-Output "Existing CNAME Record: $($existingCnameList | ConvertTo-Json)"
    if ($existingCnameList[0].data -eq "$($appname).azurewebsites.net.") {
        Write-Output "The existing CNAME record matches the Azure Web App."
    } else {
        Write-Error "The existing CNAME record does not match the Azure Web App. "
        exit -1
    }
} else {
    Write-Output "No existing CNAME record found for $domainHost."
    $cnameRecord = Invoke-WebRequest -Uri "https://api.domeneshop.no/v0/domains/$domainId/dns" -Method Post `
        -Headers @{Authorization = $auth} `
        -ContentType "application/json" `
        -Body (@{
    host = $domainHost
    ttl = 3600
    type = $isRoot ? "ANAME" : "CNAME" 
    data = "$($appname).azurewebsites.net"
    } | ConvertTo-Json)

    Write-Output "CNAME Record Response: $($cnameRecord.Content)"
}
    '''
  }
}