サブスクリプションの実装を構築する

dependencies {
  ...
  implementation "com.squareup.okhttp3:okhttp:4.12.0"
}

import androidx.compose.foundation.layout.Column
import androidx.compose.material3.Button
import androidx.compose.material3.OutlinedTextField
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch
import okhttp3.MediaType.Companion.toMediaType
import okhttp3.OkHttpClient
import okhttp3.Request
import okhttp3.RequestBody.Companion.toRequestBody
import org.json.JSONObject

@Composable
fun RegisterView() {
    var email by remember { mutableStateOf("") }
    Column {
        OutlinedTextField(value = email,
            label = { Text(text = "Email") },
            onValueChange = { email = it })
        Button(onClick = {
            val body = JSONObject().put("email", email).toString()
                .toRequestBody("application/json".toMediaType())
            val request =
                Request.Builder().url("http://10.0.2.2:4567/create-customer").post(body).build()
            CoroutineScope(Dispatchers.IO).launch {
                OkHttpClient().newCall(request).execute().use { response ->
                    if (response.isSuccessful) {
                        println(JSONObject(response.body!!.string()).get("customer"))
                    }
                }
            }
        }) {
            Text(text = "Submit")
        }
    }
}

import okhttp3.MediaType.Companion.toMediaType
import okhttp3.OkHttpClient
import okhttp3.Request
import okhttp3.RequestBody.Companion.toRequestBody
import org.json.JSONObject

fun createSubscription(priceId: String, customerId: String): SubscriptionResponse? {
    val body = JSONObject()
        .put("priceId", priceId)
        .put("customerId", customerId).toString()
        .toRequestBody("application/json".toMediaType())
    val request =
        Request.Builder().url("http://10.0.2.2:4567/create-subscription").post(body).build()
    OkHttpClient().newCall(request).execute().use { response ->
        if (response.isSuccessful) {
            // SubscriptionsResponse is data class conforming to the expected response from your backend.
            // It should include the client_secret, as discussed below.
            return Gson().fromJson(response.body!!.string(), SubscriptionResponse::class.java)
        }
    }
    return null
}

{
  "id": "sub_JgRjFjhKbtD2qz",
  "object": "subscription",
  "application_fee_percent": null,
  "automatic_tax": {
    "disabled_reason": null,
    "enabled": false,
    "liability": "null"
  },
  "billing_cycle_anchor": 1623873347,

import androidx.compose.material3.Button
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import com.stripe.android.paymentsheet.PaymentSheet
import com.stripe.android.paymentsheet.PaymentSheetResult
import com.stripe.android.paymentsheet.rememberPaymentSheet

@Composable
fun SubscribeView(clientSecret: String) {
    val paymentSheet = rememberPaymentSheet(::onPaymentSheetResult)

    Button(onClick = {
        paymentSheet.presentWithPaymentIntent(
            clientSecret, PaymentSheet.Configuration(
                primaryButtonLabel = "Subscribe for $15/month",
                merchantDisplayName = "My merchant name",
                // Set `allowsDelayedPaymentMethods` to true if your business handles
                // delayed notification payment methods like US bank accounts.
                allowsDelayedPaymentMethods = true
            )
        )
    }) {
        Text(text = "Subscribe")
    }
}

fun onPaymentSheetResult(paymentSheetResult: PaymentSheetResult) {
    when (paymentSheetResult) {
        is PaymentSheetResult.Canceled -> {
            print("Canceled")
        }

        is PaymentSheetResult.Failed -> {
            print("Error: ${paymentSheetResult.error}")
        }

        is PaymentSheetResult.Completed -> {
            // Display for example, an order confirmation screen
            print("Completed")
        }
    }
}

fun cancelSubscription(subscriptionId: String): SubscriptionResponse? {
    val body = JSONObject().put("subscriptionId", subscriptionId).toString()
        .toRequestBody("application/json".toMediaType())
    val request =
        Request.Builder().url("http://10.0.2.2:4567/cancel-subscription").post(body).build()
    OkHttpClient().newCall(request).execute().use { response ->
        if (response.isSuccessful) {
            return Gson().fromJson(response.body!!.string(), SubscriptionResponse::class.java)
        }
    }
    return null
}