java 36 lines · 6 steps

Customizing Flyway migrations in Spring

A Spring config class builds a fully customized Flyway instance and controls exactly how migrations run at startup.

Explained by highlit
Spring Intermediate database-migrations flyway dependency-injection configuration startup
1package com.acme.billing.config;
2 
3import org.flywaydb.core.Flyway;
4import org.flywaydb.core.api.MigrationVersion;
5import org.flywaydb.core.api.configuration.FluentConfiguration;
6import org.springframework.boot.autoconfigure.flyway.FlywayMigrationStrategy;
7import org.springframework.context.annotation.Bean;
8import org.springframework.context.annotation.Configuration;
9 
10import javax.sql.DataSource;
11 
12@Configuration
13public class FlywayConfig {
14 
15 @Bean
16 public Flyway flyway(DataSource dataSource) {
17 FluentConfiguration configuration = Flyway.configure()
18 .dataSource(dataSource)
19 .locations("classpath:db/migration")
20 .baselineOnMigrate(true)
21 .baselineVersion(MigrationVersion.fromVersion("0"))
22 .table("schema_history")
23 .validateOnMigrate(true)
24 .cleanDisabled(true);
25 
26 return configuration.load();
27 }
28 
29 @Bean
30 public FlywayMigrationStrategy migrationStrategy() {
31 return flyway -> {
32 flyway.repair();
33 flyway.migrate();
34 };
35 }
36}
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1Defining your own Flyway bean overrides Spring Boot's auto-configured defaults so you control every migration setting.
  2. 2baselineOnMigrate lets Flyway adopt an existing non-empty database instead of failing on first run.
  3. 3A FlywayMigrationStrategy replaces the default migrate-on-startup behavior with your own sequence of steps.

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