Don't cascade deletion of host sources, instead delete the rules async

app/src/main/java/com/frostnerd/smokescreen/activity/DnsRuleActivity.kt

@@ -84,6 +84,7 @@ class DnsRuleActivity : BaseActivity() {
                             val pos = sourceAdapterList.indexOf(it)
                             sourceAdapterList.removeAt(pos)
                             sourceAdapter.notifyItemRemoved(pos)
+                            getDatabase().dnsRuleRepository().deleteAllFromSourceAsync(it)
                             getDatabase().hostSourceRepository().deleteAsync(it)
                             dialog.dismiss()
                         }, getString(R.string.all_no) to { dialog, _ ->

app/src/main/java/com/frostnerd/smokescreen/database/dao/DnsRuleDao.kt

@@ -53,4 +53,7 @@ interface DnsRuleDao {
 
     @Query("SELECT target FROM DnsRule WHERE host=:host AND type = :type LIMIT 1")
     fun findRuleTarget(host:String, type:Record.TYPE):String?
+
+    @Query("DELETE FROM DnsRule WHERE importedFrom=:sourceId")
+    fun deleteAllFromSource(sourceId: Long)
 }
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app/src/main/java/com/frostnerd/smokescreen/database/entities/DnsRule.kt

@@ -28,7 +28,7 @@ import org.minidns.record.Record
         entity = HostSource::class,
         parentColumns = arrayOf("id"),
         childColumns = arrayOf("importedFrom"),
-        onDelete = ForeignKey.CASCADE
+        onDelete = ForeignKey.NO_ACTION
     )],
     indices = [Index("importedFrom"), Index("host"), Index("host", "type")]
     )

app/src/main/java/com/frostnerd/smokescreen/database/repository/DnsRuleRepository.kt

@@ -2,26 +2,27 @@ package com.frostnerd.smokescreen.database.repository
 
 import com.frostnerd.smokescreen.database.dao.DnsQueryDao
 import com.frostnerd.smokescreen.database.dao.DnsRuleDao
+import com.frostnerd.smokescreen.database.entities.HostSource
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.launch
 
 /*
  * Copyright (C) 2019 Daniel Wolf (Ch4t4r)
- * 
+ *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or
  * (at your option) any later version.
- 
+
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
- 
+
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- * 
+ *
  * You can contact the developer at daniel.wolf@frostnerd.com.
  */
 class DnsRuleRepository(val dnsRuleDao: DnsRuleDao) {
@@ -31,4 +32,10 @@ class DnsRuleRepository(val dnsRuleDao: DnsRuleDao) {
             dnsRuleDao.deleteAll()
         }
     }
+
+    fun deleteAllFromSourceAsync(hostSource: HostSource, coroutineScope: CoroutineScope = GlobalScope) {
+        coroutineScope.launch {
+            dnsRuleDao.deleteAllFromSource(hostSource.id)
+        }
+    }
 }
\ No newline at end of file