Run flyway explicitly

src/main/java/com/petshop/backend/BackendApplication.java

@@ -1,6 +1,7 @@
 package com.petshop.backend;
 
-import org.springframework.boot.SpringApplication;
+import com.petshop.backend.config.FlywayContextInitializer;
+import org.springframework.boot.builder.SpringApplicationBuilder;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.data.web.config.EnableSpringDataWebSupport;
 
@@ -8,6 +9,8 @@ import org.springframework.data.web.config.EnableSpringDataWebSupport;
 @EnableSpringDataWebSupport(pageSerializationMode = EnableSpringDataWebSupport.PageSerializationMode.VIA_DTO)
 public class BackendApplication {
     public static void main(String[] args) {
-        SpringApplication.run(BackendApplication.class, args);
+        new SpringApplicationBuilder(BackendApplication.class)
+                .initializers(new FlywayContextInitializer())
+                .run(args);
     }
 }

src/main/java/com/petshop/backend/DevStackApplication.java

@@ -1,5 +1,6 @@
 package com.petshop.backend;
 
+import com.petshop.backend.config.FlywayContextInitializer;
 import org.springframework.boot.builder.SpringApplicationBuilder;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.event.ContextClosedEvent;
@@ -30,7 +31,9 @@ public class DevStackApplication {
 
         try {
             controller.startDatabase();
-            context = new SpringApplicationBuilder(BackendApplication.class).run(args);
+            context = new SpringApplicationBuilder(BackendApplication.class)
+                    .initializers(new FlywayContextInitializer())
+                    .run(args);
             ConfigurableApplicationContext appContext = context;
             context.addApplicationListener(event -> {
                 if (event instanceof ContextClosedEvent) {

src/main/java/com/petshop/backend/config/FlywayContextInitializer.java

@@ -0,0 +1,40 @@
+package com.petshop.backend.config;
+
+import org.flywaydb.core.Flyway;
+import org.flywaydb.core.api.MigrationVersion;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.env.ConfigurableEnvironment;
+
+import java.util.Arrays;
+
+public class FlywayContextInitializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {
+
+    @Override
+    public void initialize(ConfigurableApplicationContext applicationContext) {
+        ConfigurableEnvironment environment = applicationContext.getEnvironment();
+
+        String url = environment.getProperty("spring.datasource.url");
+        String username = environment.getProperty("spring.datasource.username");
+        String password = environment.getProperty("spring.datasource.password");
+
+        if (url == null || username == null || password == null) {
+            throw new IllegalStateException("Datasource properties are required before startup");
+        }
+
+        String[] locations = Arrays.stream(environment
+                        .getProperty("spring.flyway.locations", "classpath:db/migration")
+                        .split(","))
+                .map(String::trim)
+                .filter(location -> !location.isEmpty())
+                .toArray(String[]::new);
+
+        Flyway.configure()
+                .dataSource(url, username, password)
+                .locations(locations)
+                .baselineOnMigrate(environment.getProperty("spring.flyway.baseline-on-migrate", Boolean.class, false))
+                .baselineVersion(MigrationVersion.fromVersion(environment.getProperty("spring.flyway.baseline-version", "1")))
+                .load()
+                .migrate();
+    }
+}