fix: Fix No transaction in context for ktor (#2483)

Author: obabichevjb

exposed-dao/build.gradle.kts

@@ -14,6 +14,5 @@ kotlin {
 dependencies {
     api(project(":exposed-core"))
 
-    // TODO change dependency level (use api or at minimum implementation dep)
-    compileOnly(project(":exposed-jdbc"))
+    implementation(project(":exposed-jdbc"))
 }

exposed-dao/src/main/kotlin/org/jetbrains/exposed/v1/dao/EntityHook.kt

@@ -1,9 +1,11 @@
 package org.jetbrains.exposed.v1.dao
 
+import org.jetbrains.exposed.v1.core.InternalApi
 import org.jetbrains.exposed.v1.core.Transaction
 import org.jetbrains.exposed.v1.core.dao.id.EntityID
+import org.jetbrains.exposed.v1.core.transactions.CoreTransactionManager
 import org.jetbrains.exposed.v1.core.transactions.transactionScope
-import org.jetbrains.exposed.v1.jdbc.transactions.TransactionManager
+import org.jetbrains.exposed.v1.jdbc.JdbcTransaction
 import java.util.Deque
 import java.util.concurrent.ConcurrentLinkedDeque
 import java.util.concurrent.ConcurrentLinkedQueue
@@ -115,13 +117,12 @@ fun Transaction.registeredChanges() = entityEvents.toList()
  *
  * The [action] will be unregistered at the end of the call to the [body] block.
  */
-// TODO add tests, at the current moment it's not used anywhere
 fun <T> withHook(action: (EntityChange) -> Unit, body: () -> T): T {
     EntityHook.subscribe(action)
     try {
         return body().apply {
-            // TODO Could it be replaces with CoreTransactionsManager?
-            TransactionManager.current().commit()
+            @OptIn(InternalApi::class)
+            (CoreTransactionManager.currentTransactionOrNull() as? JdbcTransaction?)?.commit()
         }
     } finally {
         EntityHook.unsubscribe(action)

exposed-r2dbc/src/main/kotlin/org/jetbrains/exposed/v1/r2dbc/statements/R2dbcConnectionImpl.kt

@@ -12,7 +12,6 @@ import kotlinx.coroutines.reactive.awaitFirst
 import kotlinx.coroutines.reactive.awaitFirstOrNull
 import kotlinx.coroutines.reactive.awaitSingle
 import kotlinx.coroutines.reactive.collect
-import kotlinx.coroutines.withContext
 import org.jetbrains.exposed.v1.core.statements.StatementType
 import org.jetbrains.exposed.v1.core.statements.api.ExposedSavepoint
 import org.jetbrains.exposed.v1.core.vendors.MysqlDialect
@@ -216,14 +215,26 @@ class R2dbcConnectionImpl(
 
     private var localConnection: Connection? = null
 
-    private suspend fun <T> withConnection(body: suspend Connection.() -> T): T = withContext(scope.coroutineContext) {
+    // TODO Recheck the reason of creating new context with `scope.coroutineContext`
+    //   It couses the issues `No transaction in context` if Exposed is used inside ktor server
+    //   To reproduce the problem it's enough to run the following script with any table Customers inside the server code
+    //   runBlocking {
+    //        val database = R2dbcDatabase.connect("r2dbc:h2:mem:///testdb;DB_CLOSE_DELAY=-1")
+    //        suspendTransaction(db = database) {
+    //            SchemaUtils.create(Customers)
+    //        }
+    //    }
+    //
+    //    Old function definition
+    //    private suspend fun <T> withConnection(body: suspend Connection.() -> T): T = withContext(scope.coroutineContext) {
+    private suspend fun <T> withConnection(body: suspend Connection.() -> T): T {
         if (localConnection == null) {
             localConnection = connection.awaitFirst().also {
                 // this starts an explicit transaction with autoCommit mode off
                 it.beginTransaction().awaitFirstOrNull()
             }
         }
-        localConnection!!.body()
+        return localConnection!!.body()
     }
 }
 

exposed-tests/src/test/kotlin/org/jetbrains/exposed/v1/tests/shared/entities/EntityHookTest.kt

@@ -1,4 +1,5 @@
 package org.jetbrains.exposed.v1.tests.shared.entities
+
 import org.jetbrains.exposed.v1.core.*
 import org.jetbrains.exposed.v1.core.ReferenceOption
 import org.jetbrains.exposed.v1.core.dao.id.EntityID
@@ -332,4 +333,30 @@ class EntityHookTest : DatabaseTestsBase() {
             assertEquals(2, hookCalls)
         }
     }
+
+    @Test
+    fun testWithHook() {
+        withTables(EntityHookTestData.User.table) {
+            var hookCalls = 0
+
+            withHook({ hookCalls++ }) {
+                val user = EntityHookTestData.User.new {
+                    name = "name 1"
+                    age = 25
+                }
+                user.flush()
+
+                user.name = "name 2"
+            }
+
+            assertEquals(2, hookCalls)
+
+            // Change value outside the 'withHook'
+            val user = EntityHookTestData.User.all().first()
+            user.name = "name 3"
+            user.flush()
+
+            assertEquals(2, hookCalls)
+        }
+    }
 }