also seems like your problem is due to directly ma...

# ktor

[sp]

also seems like your problem is due to directly mapping query params to a data class

[tjb]

hmm

[tjb]

the tags in my example is the JSON body

[sp]

Could you try and print tags and show us the output

[tjb]

Capture.PNG

[tjb]

@sp ^

[sp]

okay well that makes sense

[sp]

your class is somehow being parsed to a LinkedHashMap

[tjb]

i guess why? i was googling and it said jackson doesnt have enought information about the class but im not sure what that means

[sp]

but it’s correctly parsing it as a list

[sp]

doubt it

[sp]

jackson fails with other errors

[sp]

I would have a look ath documentation for the receive function

[tjb]

ill take a look

[tjb]

interesting

[tjb]

it does not work with a List but serializes fine if only a single object

[obobo]

Seems like the problem is that receive() loses the generic type information. Look at Extensions.kt in the jackson kotlin module, they wrap the generic information in a TypeReference. receive would have to do something similar, but I'm not sure how, since the wrapper would be specific to the content negotiation implementation.

[andev]

https://github.com/ktorio/ktor/issues/377

[tjb]

i just commented on this but is there a workaround for this?

[obobo]

You could inject a jacksonObjectMapper directly into your controller and receive a String or byte array and parse that into your domain object.

[tjb]

i came up with this extension function

[tjb]

inline fun <reified T> String.serialize(): T {
  return jacksonObjectMapper().readValue(this)
}

for those interested

[tjb]

usage:

val tags = call.receiveText().serialize<List<Tag>>()