AppSettings.Get() Not working for string arrays

ServiceStack
1

If I add to appSettings.json:

"test" : "some value";

I can then get that value like this:

var test = AppSettings.Get<string>("test");

However, If I add:

"test2" : [ "val1", "val2", "val3" ]

Then the following doesn’t work:

var test2 = AppSettings.Get<string[]>("test2");

It seems impossible to get it to read a string array.

I am using asp.net core 2.1. I have tried version 5.4 and also tried 5.4.1 from myget. Same issue.

This is causing the new FacebookAuthProvider to not request correct permissions because this line doesn’t read the permissions:

appSettings.Get<string[]>("oauth.facebook.Permissions", TypeConstants.EmptyStringArray);

I have isolated issue in new project using dotnet new angular-spa project and trying to read string array. It wont read a json string array.

I’ve been going in circles on this for a while. Have I missed something or is this a bug?

2

Use AppSettings.GetList() API to get an array of items, the Get API is for a complex type in a single string value, e.g containing a comma delimited list

3

Can you give me an explicit example please because when I try to set this:

  "oauth.facebook.Permissions": "email,user_friends",

It generates exception:

An error occurred while starting the application.
Internal Server Error
An error occurred while starting the application.
ConfigurationErrorsException:
NullReferenceException: Object reference not set to an instance of an object.
ServiceStack.Text.TranslateListWithElements.TranslateToConvertibleGenericICollectionCache(object from, Type toInstanceOfType, Type fromElementType)

The oauth.facebook.Permissions setting had an invalid format. The value “email,user_friends” could not be cast to type System.String
ServiceStack.NetCoreAppSettings.Bind(IConfigurationSection config)

NullReferenceException: Object reference not set to an instance of an object.
ServiceStack.Text.TranslateListWithElements.TranslateToConvertibleGenericICollectionCache(object from, Type toInstanceOfType, Type fromElementType)
ServiceStack.AutoMappingUtils.ConvertTo(object from)
ServiceStack.NetCoreAppSettings.Bind(IConfigurationSection config)

Show raw exception details
System.NullReferenceException: Object reference not set to an instance of an object.
at ServiceStack.Text.TranslateListWithElements.TranslateToConvertibleGenericICollectionCache(Object from, Type toInstanceOfType, Type fromElementType)
at ServiceStack.AutoMappingUtils.ConvertTo[T](Object from)
at ServiceStack.NetCoreAppSettings.Bind[T](IConfigurationSection config)
ConfigurationErrorsException: The oauth.facebook.Permissions setting had an invalid format. The value “email,user_friends” could not be cast to type System.String
ServiceStack.NetCoreAppSettings.Bind(IConfigurationSection config)

NullReferenceException: Object reference not set to an instance of an object.
ServiceStack.Text.TranslateListWithElements.TranslateToConvertibleGenericICollectionCache(object from, Type toInstanceOfType, Type fromElementType)
ServiceStack.AutoMappingUtils.ConvertTo(object from)
ServiceStack.NetCoreAppSettings.Bind(IConfigurationSection config)

How exactly should it appear in appSettings.json?

4

If it’s in your appsettings.json like:

{
  "oauth.facebook.Permissions": [ "email", "user_location" ]
}

It can be read like:

var permissions = AppSettings.GetList("oauth.facebook.Permissions");

But I’ve just added support for deserializing a JSON array collection into an enumerable collection in this commit, so you can also do:

var permissions = AppSettings.Get<string[]>("oauth.facebook.Permissions");

This change is available from v5.4.1 that’s now available on MyGet.

5

Hi Mythz,

Many thaks for implementing that. Prior to commit what format was this line of code you wrote in FacebookAuthProvider expecting?

appSettings.Get<string[]>("oauth.facebook.Permissions", TypeConstants.EmptyStringArray);
6

Was meant to handle a comma delimited list in a single string value, but there was an issue with the ConvertTo API fallback in deserializing string values which was also resolved on MyGet.

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