I'm having an issue with a simple GET request in Retrofit.
I'm getting data from API that returns many pairs that I don't really need, so I just focused on the elements that I need to parse when it comes to this specific request.
To get an idea, this is how the response looks:
[
{
"buildingID": 0,
"buildingName": "string",
"description": "string",
"address": "string",
"type": 0,
"rooms": [
{
...
}
],
"reservations": [
{
...
}
]
...
}
I'd just like to pull a few pairs out of it, so I created a following data class:
#JsonClass(generateAdapter = true)
data class BuildingJson(#field:Json(name = "buildingID") val buildingID: Int,
#field:Json(name = "buildingName") val name: String,
#field:Json(name = "description") val description: String,
#field:Json(name = "address") val address: String,
#field:Json(name = "type") val type: Int)
and this is how my retrofit&moshi instance looks like (Singleton.kt):
object Singleton {
val okhttp = OkHttpClient.Builder()
.addInterceptor(HttpLoggingInterceptor().apply {
level = HttpLoggingInterceptor.Level.BODY
})
.build()
val moshi = Moshi.Builder().build()
const val BASE_URL = "https://localhost:5001/api/"
val retrofit = Retrofit.Builder()
.baseUrl(BASE_URL)
.client(okhttp)
.addConverterFactory(MoshiConverterFactory.create())
.build()
val service = retrofit.create(BookitAPI::class.java)
}
And this is how my Retrofit interface for a call looks like (wrapped in BookitAPI.kt):
interface BookitAPI {
#GET("v1/BuildingApi")
fun getBuildings(): Call<List<BuildingJson>>
}
This all gets called in repository with the following code:
val buildingResponse = service.getBuildings().enqueue(object : Callback<List<BuildingJson>> {
override fun onFailure(call: Call<List<BuildingJson>>, t: Throwable) {
TODO("Not yet implemented")
}
override fun onResponse(
call: Call<List<BuildingJson>>,
response: Response<List<BuildingJson>>
) {
TODO("Not yet implemented")
}
})
The problem is that when I run this code, I get the following error:
java.lang.IllegalArgumentException: Unable to create converter for java.util.List<mylab.bookitphoneapp.models.BuildingJson>
for method BookitAPI.getBuildings
Does anyone have an idea how should I implement this converter that fails to be created? I've checked many resources but I still couldn't find an issue that's similar to this one.
Thanks!
I have a Sticker class and its wrapper:
#JsonClass(generateAdapter = true)
class StickerDto(
#Json (name = "totalAnimatedStickers") val total: Int,
#Json(name = "pages") val pages: Int,
#Json(name = "data") val stickers: List<Sticker>
)
#JsonClass(generateAdapter = true)
class Sticker(
#Json(name = "name") val name: String,
#Json(name = "id") val id: String,
#Json(name = "stickerData") val stickerData: JsonObject,
var isSelected:Boolean = false
)
The stickerData attribute comes from the api with a dynamic json object with unknown attributes
"stickerData": {}
How do I deserialize an object like that using Moshi?
My current retrofit client:
private fun createNewFriendsClient(authRefreshClient: AuthRefreshClient,
preferencesInteractor: PreferencesInteractor): FriendsApiClient {
val logger = run {
val httpLoggingInterceptor = HttpLoggingInterceptor()
httpLoggingInterceptor.apply {
httpLoggingInterceptor.level = if (BuildConfig.DEBUG) HttpLoggingInterceptor.Level.BODY else HttpLoggingInterceptor.Level.NONE
}
}
val okHttp = OkHttpClient.Builder().addInterceptor(logger).authenticator(RefreshUserAuthenticator(authRefreshClient, preferencesInteractor,
UnauthorizedNavigator(SDKInternal.appContext, Interactors.preferences))).build()
return Retrofit.Builder()
.client(okHttp)
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.addConverterFactory(MoshiConverterFactory.create())
.baseUrl(Interactors.apiEndpoint)
.build()
.create(FriendsApiClient::class.java)
}
Gives me an
"Unable to create converter for class StickerDto"
Caused by NoJsonAdapter for java.util.Comparator<? super java.lang.String>
error. What converter do I need to use if not that Moshi one? Trying to pull it down as a string also gives an error as it is expecting and object. I just need that string.
Edit, the Json string is very long but it begins like this:
{"tileId":"1264373a-24d8-4c10-ae90-d6e8f671410c","friendId":"2c50f187-039a-4f85-b12b-0c802396a611","name":"David Carey","message":"Joined WeAre8","animatedSticker":{"v":"5.5.7","fr":24,"ip":0,"op":48,"w":1024,"h":1024,"nm":"party_popper","ddd":0,"assets":[{"id":"comp_0","layers":[{"ddd":0,"ind":1,"ty":3,"nm":"C | Position","sr":1,"ks":{"o":{"a":0,"k":100,"ix":11},"r":{"a":0,"k":45,"ix":10},"p":{"a":1,"k":[{"i":{"x":0,"y":1},"o":{"x":0.333,"y":0},"t":0,"s":[176,892,0],"to":[-6.667,6.667,0],"ti":[0,0,0]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.333,"y":0},"t":7,"s":[136,932,0],"to":[0,0,0],"ti":[-6.667,6.667,0]},{"t":11,"s":[176,892,0]}],"ix":2},"a":{"a":0,"k":[0,0,0],"ix":1},"s":{"a":1,"k":[{"i":{"x":[0,0,0.667],"y":[1,1,1]},"o":{"x":[0.333,0.333,0.333],"y":[0,0,0]},"t":0,"s":[100,100,100]},{"i":{"x":[0.833,0.833,0.833],"y":[0.833,0.833,1]},"o":{"x":[0.333,0.333,0.333],"y":[0,0,0]},"t":7,"s":[115,75,100]},{"i":{"x":[0,0,0.667],"y":[1,1,1]},"o":{"x":[0.167,0.167,0.167],"y":[0.167,0.167,0]},"t":11,"s":[95,105,100]},{"t":20,"s":[100,100,100]}],"ix":6}},"ao":0,"ef":[{"ty":5,"nm":"Controller","np":13,"mn":"Pseudo/DUIK controller","ix":1,"en":1,"ef":[{"ty":6,"nm":"Icon","mn":"Pseudo/DUIK controller-0001","ix":1,"v":0},{"ty":2,"nm":"Color","mn":"Pseudo/DUIK controller-0002","ix":2,"v":{"a":0,"k":[0.92549020052,0.0941176489,0.0941176489,1],"ix":2}},{"ty":3,"nm":"Position","mn":"Pseudo/DUIK controller-0003","ix":3,"v":{"a":0,"k":[0,0],"ix":3}},{"ty":0,"nm":"Size","mn":"Pseudo/DUIK controller-0004","ix":4,"v":{"a":0,"k":100,"ix":4}},{"ty":0,"nm":"Orientation","mn":"Pseudo/DUIK controller-0005
Note that JsonObject is a class from the gson package, so if you want to use Moshi you will need to switch to JSONObject which is the default class supported by Android.
To do this you will need to write your own JSONObject adapter.
First, write your adapter class:
import com.squareup.moshi.FromJson
import com.squareup.moshi.JsonReader
import com.squareup.moshi.JsonWriter
import com.squareup.moshi.ToJson
import okio.Buffer
import org.json.JSONException
import org.json.JSONObject
class JSONObjectAdapter {
#FromJson
fun fromJson(reader: JsonReader): JSONObject? {
// Here we're expecting the JSON object, it is processed as Map<String, Any> by Moshi
return (reader.readJsonValue() as? Map<String, Any>)?.let { data ->
try {
JSONObject(data)
} catch (e: JSONException) {
// Handle exception
return null
}
}
}
#ToJson
fun toJson(writer: JsonWriter, value: JSONObject?) {
if (value != null) {
writer.value(Buffer().writeUtf8(value.toString()))
} else {
writer.value(null as String?)
}
}
}
Adjust your retrofit build to provide custom Moshi object when creating the MoshiConverterFactory:
.addConverterFactory(MoshiConverterFactory.create(Moshi.Builder().add(JSONObjectAdapter()).build()))
and then you are good to go and use JSONObject
#Json(name = "stickerData") val stickerData: JSONObject
Good luck and I hope this helps!
Built-in Type Adapters for Moshi include Arrays, Collections, Lists, Sets, and Maps. A JsonObject type is not provided with Moshi itself, but it would be an enhanced Map<String, Any> anyhow, so just use the Map instead of an object.
#JsonClass(generateAdapter = true)
class Sticker(
#Json(name = "name") val name: String,
#Json(name = "id") val id: String,
#Json(name = "stickerData") val stickerData: Map<String, Any>,
var isSelected: Boolean = false
)
The values are automatically converted as well. Thus you'll find strings, lists or numbers there.
I made stickerData into a Map and used a GsonConverterFactory instead of Moshi.
help me for this issue please, I want to get data from API
{
"status": true,
"data": [
{
"id_pelanggan": "456",
"nama_pelanggan": "ahmad",
"alamat": "taliwang"
},
{
"id_pelanggan": "457",
"nama_pelanggan": "ahmad",
"alamat": "taliwang"
}
]}
this is my API object for setup for dynamic class, retrofit2 and gson
object Api {
private val BASE_URL: String = BuildConfig.API_SRAPP
private var gson = GsonBuilder().setLenient().create()
private val httpClient = OkHttpClient.Builder()
fun <T>service(java: Class<T>): T{
val retrofit = Retrofit.Builder()
.addConverterFactory(ScalarsConverterFactory.create())
.addConverterFactory(GsonConverterFactory.create(gson))
.baseUrl(BASE_URL)
.client(httpClient.build())
.build()
return retrofit.create(java)
}
}
this is my class BaseRespon for handle all data from API and with dynamic class
data class BaseResponse<T>(
val status: Boolean,
val data: T?
)
this is my class Customer
data class Customer (
#SerializedName("id_pelanggan")
#Expose
val idPelanggan: String,
#SerializedName("nama_pelanggan")
#Expose
val namaPelanggan: String,
#SerializedName("alamat")
#Expose
val alamat: String
)
this is my API service
interface CustomerServices {
#GET("customer")
fun getAllCustomer(#Header("Authorization") auth: String): Call<BaseResponse<ArrayList<Customer>>>
#GET("customer")
fun getCustomerbyID(#Header("Authorization") auth: String, #Query("id") id: String): Call<BaseResponse<Customer>>
}
and this is my class for using API
class CustomerPresenter {
fun loadAllCustomer(){
apiCustomer.getAllCustomer(OfflineHelper.getToken())
.enqueue(object : Callback<BaseResponse<ArrayList<Customer>>>{
override fun onFailure(call: Call<BaseResponse<ArrayList<Customer>>>, t: Throwable) {
Log.e("allCustomer", "${t.message}")
}
override fun onResponse(
call: Call<BaseResponse<ArrayList<Customer>>>,
response: Response<BaseResponse<ArrayList<Customer>>>
) {
saveLocalCustomer(response.body())
}
})
}
fun saveLocalCustomer(data: BaseResponse<ArrayList<Customer>>?){
Log.w("loadedAll", "${data?.status}")
}
and I have log failure in loadAllCustomer
java.lang.IllegalStateException: Expected BEGIN_OBJECT but was STRING at line 2 column 1 path $
I don't understand why it's failure, my endpoint is not typo, and I have tested it on postman
You need to use a List as your return type for the data field. try this:
data class BaseResponseList<T>(
val status: Boolean,
val data: List<T>?
)
and then using BaseResponseList in your call as following:
#GET("customer")
fun getAllCustomer(#Header("Authorization") auth: String): Call<BaseResponseList<Customer>>
Use BaseResponseList for any endpoint that returns a List, and BaseResponse for Objects
Update your response class and api interface like below
data class BaseResponse(
val status: Boolean,
val data: List<Customer>?
)
interface CustomerServices {
#GET("customer")
fun getAllCustomer(#Header("Authorization") auth: String): Call<BaseResponse>
#GET("customer")
fun getCustomerbyID(#Header("Authorization") auth: String, #Query("id") id: String): Call<Customer>
}
your model not same with you object json
I have trouble to parse some inner part of JSON (with Moshi) that can vary from a lot and is highly unstructured. Overall it looks like:
response: {
items: [{
type: "typeA",
data: {
"1563050214700-001": {
foo: 123 ....
}
}
}, {
type: "typeB",
data: {
"1563050214700-002": {[
// differs a lot from previous one
{bar: 123 .... }
]}
}
}]
}
And data class structure looks like:
data class Response(
val items: Map<String,List<Item?>>?
) {
data class Item(
val type: String?,
val data: Map<String,List<DataItem?>>?
) {
data class DataItem(
// members highly unstructured
)
}
}
Schema of "DataItem" varies a lot. Looks like Moshi codegen supports adapters that can potentially allow manual parsing of these inner data classes but I'm not able to find the right tutorial or example. Ideally, I want entire Response parsed just as if it were a well-defined JSON.
Here is how I use retrofit/moshi
#Provides
#Singleton
#MyApp
fun provideMyAppRetrofit(context: Context, #MyApp okHttpClient: OkHttpClient): Retrofit {
return Retrofit.Builder()
.client(okHttpClient)
.addConverterFactory(MoshiConverterFactory.create())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.baseUrl(context.getString(R.string.APP_BASE_URL))
.build()
}
#Provides
#Singleton
fun provideMyAppApiService(#MyApp retrofit: Retrofit): MyAppApiService {
return retrofit.create(MyAppApiService::class.java)
}
How do I achieve this? Any sample or reference implementation will be helpful.
welcome to the polymorphic JSON parsing problems word!
We were writing own JSON adapters that are looking like:
internal class CardJsonAdapter(
moshi: Moshi
) : JsonAdapter<Card>() {
private val cardTypeAdapter = moshi.adapter(Card.Type::class.java)
private val amountsWithActionAdapter = moshi.adapter(AmountsWithActionCard::class.java)
private val backgroundImageCardAdapter = moshi.adapter(BackgroundImageCard::class.java)
#Suppress("TooGenericExceptionCaught")
override fun fromJson(reader: JsonReader): Card = try {
#Suppress("UNCHECKED_CAST")
val jsonMap = reader.readJsonValue() as Map<String, Any?>
val type = cardTypeAdapter.fromJsonValue(jsonMap["type"])
createCardWithType(type, jsonMap)
} catch (error: Exception) {
if (BuildConfig.DEBUG) {
Log.w("CardJsonAdapter", "Failed to parse card", error)
}
// Try not to break the app if we get unexpected data: ignore errors and return a placeholder card instead.
UnknownCard
}
override fun toJson(writer: JsonWriter, value: Card?) {
throw NotImplementedError("This adapter cannot write cards to JSON")
}
private fun createCardWithType(type: Type?, jsonMap: Map<String, Any?>) = when (type) {
null -> UnknownCard
Type.AMOUNTS_WITH_ACTION -> amountsWithActionAdapter.fromJsonValue(jsonMap)!!
Type.BACKGROUND_IMAGE_WITH_TITLE_AND_MESSAGE -> backgroundImageCardAdapter.fromJsonValue(jsonMap)!!
}
}
However, it is not anymore required. Moshi supports polymorphic JSON parsing now - https://proandroiddev.com/moshi-polymorphic-adapter-is-d25deebbd7c5
Make a custom adapter
class YourAdapter {
#FromJson
fun fromJson(reader: JsonReader, itemsAdapter: JsonAdapter<ItemsResponse>): List<ItemsResponse>? {
val list = ArrayList<ItemsResponse>()
if (reader.hasNext()) {
val token = reader.peek()
if (token == JsonReader.Token.BEGIN_ARRAY) {
reader.beginArray()
while (reader.hasNext()) {
val itemResponse = itemsAdapter.fromJsonValue(reader.readJsonValue())
itemsResponse?.let {
list.add(itemResponse)
}
}
reader.endArray()
}
}
return list
}
}
I have parse the data from this link
https://api.androidhive.info/contacts/
But I am getting error as
E/on Failure :: retrofit errorjava.lang.IllegalStateException: Expected BEGIN_ARRAY but was BEGIN_OBJECT at line 1 column 2 path $
Below is the code which I done.
class RetrofitService {
val liveUserResponse:MutableLiveData<List<ContactBase>> = MutableLiveData()
companion object Factory {
var gson = GsonBuilder().setLenient().create()
fun create(): ApiInterface {
Log.e("retrofit","create")
val retrofit = Retrofit.Builder()
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.addConverterFactory(GsonConverterFactory.create(gson))
.baseUrl("https://api.androidhive.info/")
.build()
return retrofit.create(ApiInterface::class.java)
}
}
fun loadContactsData(): MutableLiveData<List<ContactBase>>? {
Log.e("loadAndroidData","yes")
val retrofitCall = create().getContacts()
retrofitCall.enqueue(object : Callback<List<ContactBase>> {
override fun onFailure(call: Call<List<ContactBase>>, t: Throwable?) {
Log.e("on Failure :", "retrofit error"+t)
Log.e("on Failure :", "retrofit error"+call)
}
override fun onResponse(call: Call<List<ContactBase>>, response: retrofit2.Response<List<ContactBase>>) {
val list = response.body()
for (i in list.orEmpty()){
Log.e("on response 1:", ""+i)
}
liveUserResponse.value = list
Log.e("hasActiveObservers 1", liveUserResponse.hasActiveObservers().toString()+" check")
Log.e("on response 2 :", liveUserResponse.toString()+" check")
}
})
return liveUserResponse
}
}
But it's always going to Failure state.
data class ContactBase (val contacts : List<Contacts>)
data class Contacts (
val id : String,
val name : String,
val email : String,
val address : String,
val gender : String,
val phone : Phone
)
data class Phone (
val mobile : String,
val home : String,
val office : String
)
interface ApiInterface{
#GET("contacts/")
fun getContacts(): Call<List<ContactBase>>
}
class AndroidViewModel:ViewModel(){
private val retrofitService = RetrofitService()
fun getContactsData(): MutableLiveData<List<ContactBase>>?{
return retrofitService.loadContactsData()
}
}
I cross verified the url too and pojo class. But it always go to failure case in retrofit.
The error says that the incomming JSON starts with a { and not with a [ which means it's an object and not an array of objects.
So you should be having a class that has an array of Contact in order to make that call successful.
A small heads up: Since you are using GSON, your model classes would need the implementation of #SerializedName(string) annotation above the variables.