How to stick app config settings to a slot via bicep - azure

Question

How to stick app config settings to a slot via bicep?
Here is my bicep file:
var stagingSettings = [
{
name: 'AzureFunctionsJobHost__extensions__durableTask__hubName'
value: 'staging'
slotSetting: true
}
]
resource functionApp 'Microsoft.Web/sites/slots#2018-11-01' = {
name: name
kind: kind
location: location
properties: {
clientAffinityEnabled: true
enabled: true
httpsOnly: true
serverFarmId: resourceId('Microsoft.Web/serverfarms', servicePlanName)
siteConfig: {
use32BitWorkerProcess : false
appSettings: stagingSettings
}
}
identity: {
type: 'SystemAssigned'
}
}
On deploying this code, I don't see app config settings stick to a slot:
checkbox is not checked. What am I missing?

Answer 1

You need to create a slotConfigNames resource:
Names for connection strings, application settings, and external Azure storage account configuration
identifiers to be marked as sticky to the deployment slot and not moved during a swap operation.
This is valid for all deployment slots in an app.
Something like that should work:
param functionAppName string
resource functionApp 'Microsoft.Web/sites#2018-11-01' existing = {
name: functionAppName
}
resource functionApps 'Microsoft.Web/sites/config#2021-03-01' = {
name: 'slotConfigNames'
parent: functionApp
properties: {
// Sticky app settings
appSettingNames: [
'AzureFunctionsJobHost__extensions__durableTask__hubName'
]
}
}