Hello, I'm migrating from retrofit to ktor on andr...

# ktor

[Krystian Kaniowski]

Hello, I'm migrating from retrofit to ktor on android to enable sharing code with ios. I've done nearly everything, but I have got following problem with migration (Previously we were using retrofit interface with annotation and interceptor):
• some calls require additional authentication
• I want to add proper header with token to these calls
• I case of 401, I want to perform additional call to refresh token and then retry repeat original call with updated token
What fit best to these requirements? Should I write custom HttpClientFeature, somehow intercept such call with HttpSend, or anything else?

[Krystian Kaniowski]

this is somehow similar to https://kotlinlang.slack.com/archives/C0A974TJ9/p1720886361005409 but I have a bit more generic problem

[Krystian Kaniowski]

hmm, maybe this is the response https://ktor.io/docs/client-request-retry.html ?

[Krystian Kaniowski]

is it ok, to add some attribute to call and check in HttpRequestRetry if such call meets criteria of authorization needed?

[Aleksei Tirman [JB]]

Have you tried to use the Auth plugin with Bearer authentication, which adds the Authorization header and refreshes the token on 401?

[Krystian Kaniowski]

how to differentiate calls requiring and not requiring auth? Do I have to write to http clients, or can I do it in one (sometimes I have also optional authentication)

[Krystian Kaniowski]

it would be simlest for me if I could use for example attributes (if I'm understanding them correct as they are some tags for calls)

[Aleksei Tirman [JB]]

By default, the client makes requests without the Authorization header and only adds the header after the server responds with 401. You can use the sendWithoutRequest method to configure which requests must include the Authorization header initially.

[Krystian Kaniowski]

hmm, seems to be enough for my case, thanks very much!