feat: add a new endpoint for deleting subscription by type

Author: jinliu9508

OneSignalSDK/onesignal/core/src/main/java/com/onesignal/user/internal/backend/ISubscriptionBackendService.kt

@@ -2,6 +2,7 @@ package com.onesignal.user.internal.backend
 
 import com.onesignal.common.consistency.RywData
 import com.onesignal.common.exceptions.BackendException
+import com.onesignal.user.internal.subscriptions.SubscriptionType
 
 interface ISubscriptionBackendService {
     /**
@@ -50,6 +51,20 @@ interface ISubscriptionBackendService {
         jwt: String? = null,
     )
 
+    /**
+     * Delete an existing subscription by type
+     *
+     * @param appId The ID of the OneSignal application this subscription exists under.
+     * @param subscriptionId The ID of the subscription to delete.
+     * @param subscriptionType The type (Email or SMS) of the subscription to delete.
+     */
+    suspend fun deleteSubscription(
+        appId: String,
+        subscriptionId: String,
+        subscriptionType: SubscriptionType,
+        jwt: String? = null,
+    )
+
     /**
      * Transfer an existing subscription to the user specified.
      *

OneSignalSDK/onesignal/core/src/main/java/com/onesignal/user/internal/backend/impl/SubscriptionBackendService.kt

@@ -10,6 +10,7 @@ import com.onesignal.core.internal.http.IHttpClient
 import com.onesignal.core.internal.http.impl.OptionalHeaders
 import com.onesignal.user.internal.backend.ISubscriptionBackendService
 import com.onesignal.user.internal.backend.SubscriptionObject
+import com.onesignal.user.internal.subscriptions.SubscriptionType
 import org.json.JSONObject
 
 internal class SubscriptionBackendService(
@@ -97,6 +98,17 @@ internal class SubscriptionBackendService(
         }
     }
 
+    override suspend fun deleteSubscription(
+        appId: String,
+        subscriptionId: String,
+        subscriptionType: SubscriptionType,
+        jwt: String?
+    ) {
+        TODO("Not yet implemented")
+        // the endpoint is DELETE /by/type/:type/token/:token/subscriptions
+        
+    }
+
     override suspend fun transferSubscription(
         appId: String,
         subscriptionId: String,