[ASK] How to create sequential or parallel request?

[fjr619]

right now i'm using CoroutinesResponseCallAdapterFactory, how to create sequential request and parallel request with sandwich?
Example for sequential = i have API for getConfig and getBanner, frist getConfig, when succeed it will call getBanner
Example for parallel = API getProductDetail, getUserLimit. both API will parralel then result of 2 api will combine into 1 result

thank you

[skydoves]

Hi, you can check merge.

[fjr619]

If i look at documentation merge can only be use with ApiResponse<List>, but my requirement is not list. So i cant use that

[skydoves]

I got it.
Here is a simple example using the toFlow by ApiResponse, and combine or zip by Flow.

    val response1 = withContext(Dispatchers.IO) { pokedexClient.fetchPokemonInfo(name = name1) }
    val flow1: Flow<PokemonInfo> = response1.toFlow()

    val response2 = withContext(Dispatchers.IO) { pokedexClient.fetchPokemonInfo(name = name2) }
    val flow2: Flow<PokemonInfo> = response2.toFlow()

    val mergedFlow: Flow<String> = flow1.combine(flow2) { info1, info2 ->
      "${info1.name}, ${info2.name}"
    }

    mergedFlow.collect {
      Log.e("Test", "merged information: $it")
    }

[skydoves]

And you can handle the error case like this:

    val response1 = withContext(Dispatchers.IO) { pokedexClient.fetchPokemonInfo(name = "bulbasaur") }
    val flow1: Flow<PokemonInfo> = response1.toFlow()

    val response2 = withContext(Dispatchers.IO) {
      pokedexClient.fetchPokemonInfo(name = "Wrong name").onError {
        Log.e("Test", "You've got an error by fetching response2..") }
    }
    val flow2: Flow<PokemonInfo> = response2.toFlow()

    val mergedFlow: Flow<String> = flow1.combine(flow2) { info1, info2 ->
      "${info1.name}, ${info2.name}"
    }

    mergedFlow.collect {
      Log.e("Test", "merged information: $it")
    }

[skydoves]

And here is an example that you can just request sequentially and emit data as a single Flow.

flow {
      pokedexClient.fetchPokemonInfo(name = "bulbasaur")
        .suspendOnSuccess { emit(data?.name!! + " response1") }
        .onError {
          Log.e("Test", "You've got an error by fetching response1..")
        }

      pokedexClient.fetchPokemonInfo(name = "bulbasaur")
        .suspendOnSuccess { emit(data?.name!! + " response2") }
        .onError {
          Log.e("Test", "You've got an error by fetching response2..")
        }
    }.flowOn(Dispatchers.IO).collect {
      Log.e("Test", "collected response: $it")
    }

[fjr619]

thankyou i will explore it 👍

[chanjungkim]

@skydoves
I am trying to call APIs sequentially,

    suspend fun reCheckout(
        phoneNumber: String,
        orderId: String,
        items: ArrayList< CartItemAddBody>,
        checkoutBody: CheckoutRequestBody
    ) = flow {
        loginAndRegister(phoneNumber)
        cancelOrder(orderId, OrderCancelRequestBody("store", "re-checkout"))
        addMultiCartItem(items)
        checkOut(checkoutBody)
    }

How can I achieve it? it must be called one by one in order.