Hi there! Can somebody tell me what can cause an issue when I receive unknown `enum` value from API ...

# apollo-kotlin

[Oleksii Yerastov]

Hi there!
Can somebody tell me what can cause an issue when I receive unknown enum value from API and leads to error response?
As I can see apollo generates safeValueOf(rawValue: String) method in enum class alongside with

/**
 * Auto generated constant for unknown enum values
 */
UNKNOWN__("UNKNOWN__");

value for unknown enums. Also there is usage of this method in operator fun invoke(reader: ResponseReader) for entity that contains this enum.
Do I need to explicitly enable something to make this work so I apollo can parse unknown enum values to UNKNOWN?

[mbonnin]

Hi ! What error are you getting? I think unknown enum values should be map to UNKNOWN automatically

[mbonnin]

You can look into sealedClassesForEnumMatching if you want to read the rawValue of unknown enums

[Oleksii Yerastov]

I just receive Can't serialize value (/me/roles[2]) : Invalid input for Enum 'MyEnum'. Unknown value 'NEW_ENUM_VALUE'
in
response.response.errors
where response is ApolloResponse accessed in ApolloRequestInterceptor

[Oleksii Yerastov]

so it is not mapping to UNKNOWN and just fails during mapping of response

[mbonnin]

It sounds like this happens while serializing arguments ?

[mbonnin]

Mmm or maybe your server doesn't like NEW_ENUM_VALUE

[mbonnin]

Yep, more likely a server error

[Oleksii Yerastov]

It happens during parsing of response from server

[Oleksii Yerastov]

I receive array of enums with unknown value to client

[Oleksii Yerastov]

client 100% is not sending this enum value to server

[mbonnin]

I would expect a ApolloParseException for client parsing errors, response.errors should come from the server

[mbonnin]

Can you hook a proxy or httplogginginterceptor to rule that option out?

[Oleksii Yerastov]

it’s happening in multiplatform code so there is no httplogginginterceptor and I’ll need your guidance for further investigation)

[mbonnin]

I see. I'll be at my computer in ~20min, will dig more then

[Oleksii Yerastov]

thanks, will be waiting🙏

[mbonnin]

Is there any chance you can share your query?

[mbonnin]

To debug this further, a proxy would be quite useful, this really looks like this error is coming from the server. If a proxy is not an option, you can customize the default HttpNetworkTransport by using expect/actual. Something like:

actual fun customApolloHttpNetworkTransport(
    serverUrl: String, 
): NetworkTransport =  ApolloHttpNetworkTransport(
    serverUrl = serverUrl,
    headers = emptyMap(),
    httpCallFactory = OkHttpClient.Builder().addInterceptor(HttpLoggingInterceptor().apply{
      level = Level.BODY
    }).build(),
    httpMethod = <http://HttpMethod.Post|HttpMethod.Post>    
)

[Oleksii Yerastov]

Oh, we found the reason and it is actually some internal code on backend😣
So sorry for bothering you without checking appropriately

[mbonnin]

Cool 👍

[mbonnin]

Glad that you found the error, don't hesitate to share any feedback

[Oleksii Yerastov]

thanks!❤️