🐛 fix: PaidCommandInterceptor | handle withdraw resources from non-existing resource pool (#23)

Author: MateuszNaKodach

src/main/java/com/dddheroes/heroesofddd/resourcespool/write/ResourcesPool.java

@@ -52,4 +52,8 @@ void evolve(ResourcesWithdrawn event) {
     ResourcesPool() {
         // required by Axon
     }
+
+    public ResourcesPool(ResourcesPoolId resourcesPoolId) {
+        this.resourcesPoolId = resourcesPoolId;
+    }
 }

src/main/java/com/dddheroes/heroesofddd/resourcespool/write/withdraw/PaidCommandInterceptor.java

@@ -53,10 +53,10 @@ public Object handle(
         return interceptorChain.proceed();
     }
 
-    private void withdrawResourcesToSpend(ResourcesPoolId resourcesPoolId, Resources cost) {
+    private void withdrawResourcesToSpend(ResourcesPoolId resourcesPoolId, Resources cost) throws Exception {
         var rawResourcesPoolId = resourcesPoolId.raw();
         var withdrawResources = WithdrawResources.command(rawResourcesPoolId, cost.raw());
-        resourcesPoolRepository.load(rawResourcesPoolId)
+        resourcesPoolRepository.loadOrCreate(rawResourcesPoolId, () -> new ResourcesPool(resourcesPoolId))
                                .execute(resourcesPool -> resourcesPool.decide(withdrawResources));
     }
 }

src/test/java/com/dddheroes/heroesofddd/creaturerecruitment/write/recruitcreature/RecruitCreatureRequiresResourcesTest.java

@@ -28,7 +28,9 @@
 import static org.junit.jupiter.api.Assertions.*;
 
 @Import(TestcontainersConfiguration.class)
-@SpringBootTest
+@SpringBootTest(properties = {
+        "application.interceptors.paid-commands.enabled=true"
+})
 class RecruitCreatureRequiresResourcesTest {
 
     private static final String GAME_ID = GameId.random().raw();

src/test/java/com/dddheroes/heroesofddd/resourcespool/write/withdraw/PaidCommandInterceptorTest.java

@@ -32,7 +32,9 @@
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 @Import(TestcontainersConfiguration.class)
-@SpringBootTest
+@SpringBootTest(properties = {
+        "application.interceptors.paid-commands.enabled=true"
+})
 class PaidCommandInterceptorTest {
 
     private static final String GAME_ID = GameId.random().raw();
@@ -93,7 +95,8 @@ void givenSufficientResources_whenPaidCommandFailed_thenResourcesNotWithdrawn()
         var paidCommand = TestPaidCommand.failing(COMMAND_COST);
         assertThatThrownBy(() -> executePlayerCommand(paidCommand))
                 .cause()
-                .satisfies(e -> assertThat(e).hasMessageContaining("TestPaidCommand failed! Resources withdrawal should be rolled back"));
+                .satisfies(e -> assertThat(e).hasMessageContaining(
+                        "TestPaidCommand failed! Resources withdrawal should be rolled back"));
 
         // then
         eventStoreAssertions.assertEventNotStored(resourcesPoolId, ResourcesWithdrawn.class);
@@ -152,6 +155,19 @@ void givenResources_whenExecutingNonPaidCommand_thenNoResourcesWithdrawn() {
         eventStoreAssertions.assertEventsStoredCount(nonPaidCommand.identifier, 1);
     }
 
+    @Test
+    void givenNoResources_whenExecutingPaidCommand_thenResourcesNotWithdrewAndCommandNotExecuted() {
+        // when
+        var paidCommand = new TestPaidCommand(COMMAND_COST);
+
+        // then
+        assertThatThrownBy(() -> executePlayerCommand(paidCommand))
+                .cause()
+                .satisfies(e -> assertThat(e).hasMessageContaining("Cannot withdraw more than deposited resources"));
+        eventStoreAssertions.assertEventNotStored(resourcesPoolId, ResourcesWithdrawn.class);
+        eventStoreAssertions.assertNoEventsStored(paidCommand.identifier);
+    }
+
     private void executePlayerCommand(Command command) {
         commandGateway.sendAndWait(command, gameMetaData());
     }