Azure App Services Add array of strings in configuration

Question

Net core application and deploying the application in Azure App Services. In my application, I have an app settings.json file with below content

"Roles": {
    "Roles": [
        "Admins",
        "Users"
    ]
}

I have the below configuration in my ARM template.

Parameters.json

"Roles": {
    "value": [
        "Admins",
        "Users"
    ]
}

I am trying to add values in app settings as below

{
    "name": "Roles__Roles",
    "value": "[parameters('Roles')]" 
}

This is giving me an exception

2021-01-19T10:25:17.0538350Z ##[error]Details:
2021-01-19T10:25:17.0539754Z ##[error]undefined: HTTP request body must not be empty.

Can someone help me to fix this?

Answer 1

As far as I understand, the app settings values provided for the App Service need to be of type string. However, your parameter "Roles" is of type array. Thus, a conversion to string is required. Try this:

{
    "name": "Roles__Roles",
    "value": "[string(parameters('Roles'))]"
}

The same applies to parameters of type object.

Unfortunately, the error message is not at all helpful in clarifying this.

References:

• Microsoft Docs: Template functions - string - Azure Resource Manager
• Related question: Error passing an array type as a parameter to an appsetting for an AppService Slot